Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fix "IPv4: Attempt to release TCP socket in state 1 "... on shutdown #9

Closed
pabeni opened this issue Mar 24, 2020 · 2 comments
Closed

Comments

@pabeni
Copy link

pabeni commented Mar 24, 2020

running the following syzkaller:

# {Threaded:false Collide:false Repeat:false RepeatTimes:0 Procs:1 Sandbox: Fault:false FaultCall:-1 FaultNth:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false UseTmpDir:false HandleSegv:false Repro:false Trace:false}
r0 = socket$inet_mptcp(0x2, 0x1, 0x106)
r1 = socket$inet_mptcp(0x2, 0x1, 0x106)
bind$inet(r1, &(0x7f00000013c0)={0x2, 0x4e20, @multicast2}, 0x10)
connect$inet(r1, &(0x7f0000000040)={0x2, 0x0, @loopback}, 0x10)
listen(r1, 0x3)
connect$inet(r0, &(0x7f0000000040)={0x2, 0x4e20, @loopback}, 0x4d)
sendmsg$inet(r0, &(0x7f0000000280)={0x0, 0x0, &(0x7f0000000000)=[{&(0x7f0000000080)="ff", 0x20000081}], 0x1}, 0x0)

beyond triggering issues/3, it blocks - as expected. Explicitly killing the process yeld the following warning:

"IPv4: Attempt to release TCP socket in state 1"

The call trace to the above printk is the following one:

        7fff82f81a4a printk ([kernel.kallsyms])
        7fff8441f637 __sk_destruct ([kernel.kallsyms])
        7fff84aaecbf subflow_ulp_release ([kernel.kallsyms])
        7fff847747ae tcp_cleanup_ulp ([kernel.kallsyms])
        7fff8474c812 tcp_v4_destroy_sock ([kernel.kallsyms])
        7fff846c383a inet_csk_destroy_sock ([kernel.kallsyms])
        7fff846c42ad inet_csk_listen_stop ([kernel.kallsyms])
        7fff846e3f8c tcp_close ([kernel.kallsyms])
        7fff847c2ea6 inet_release ([kernel.kallsyms])
        7fff84408605 __sock_release ([kernel.kallsyms])
        7fff84a9fda3 mptcp_close ([kernel.kallsyms])
        7fff847c2ea6 inet_release ([kernel.kallsyms])
        7fff84408515 __sock_release ([kernel.kallsyms])
        7fff844086e4 sock_close ([kernel.kallsyms])
        7fff83591224 __fput ([kernel.kallsyms])
        7fff82e5b789 task_work_run ([kernel.kallsyms])
        7fff82df7c3a do_exit ([kernel.kallsyms])
        7fff82df9ded do_group_exit ([kernel.kallsyms])
        7fff82e24a5e get_signal ([kernel.kallsyms])
        7fff82c6777d do_signal ([kernel.kallsyms])
        7fff82c0c51f exit_to_usermode_loop ([kernel.kallsyms])
        7fff82c0ee88 do_syscall_64 ([kernel.kallsyms])
        7fff84c05091 entry_SYSCALL_64_after_hwframe ([kernel.kallsyms])
jenkins-tessares pushed a commit that referenced this issue Mar 26, 2020
When experimenting with bpf_send_signal() helper in our production
environment (5.2 based), we experienced a deadlock in NMI mode:
   #5 [ffffc9002219f770] queued_spin_lock_slowpath at ffffffff8110be24
   #6 [ffffc9002219f770] _raw_spin_lock_irqsave at ffffffff81a43012
   #7 [ffffc9002219f780] try_to_wake_up at ffffffff810e7ecd
   #8 [ffffc9002219f7e0] signal_wake_up_state at ffffffff810c7b55
   #9 [ffffc9002219f7f0] __send_signal at ffffffff810c8602
  #10 [ffffc9002219f830] do_send_sig_info at ffffffff810ca31a
  #11 [ffffc9002219f868] bpf_send_signal at ffffffff8119d227
  #12 [ffffc9002219f988] bpf_overflow_handler at ffffffff811d4140
  #13 [ffffc9002219f9e0] __perf_event_overflow at ffffffff811d68cf
  #14 [ffffc9002219fa10] perf_swevent_overflow at ffffffff811d6a09
  #15 [ffffc9002219fa38] ___perf_sw_event at ffffffff811e0f47
  #16 [ffffc9002219fc30] __schedule at ffffffff81a3e04d
  #17 [ffffc9002219fc90] schedule at ffffffff81a3e219
  #18 [ffffc9002219fca0] futex_wait_queue_me at ffffffff8113d1b9
  #19 [ffffc9002219fcd8] futex_wait at ffffffff8113e529
  #20 [ffffc9002219fdf0] do_futex at ffffffff8113ffbc
  #21 [ffffc9002219fec0] __x64_sys_futex at ffffffff81140d1c
  #22 [ffffc9002219ff38] do_syscall_64 at ffffffff81002602
  #23 [ffffc9002219ff50] entry_SYSCALL_64_after_hwframe at ffffffff81c00068

The above call stack is actually very similar to an issue
reported by Commit eac9153 ("bpf/stackmap: Fix deadlock with
rq_lock in bpf_get_stack()") by Song Liu. The only difference is
bpf_send_signal() helper instead of bpf_get_stack() helper.

The above deadlock is triggered with a perf_sw_event.
Similar to Commit eac9153, the below almost identical reproducer
used tracepoint point sched/sched_switch so the issue can be easily caught.
  /* stress_test.c */
  #include <stdio.h>
  #include <stdlib.h>
  #include <sys/mman.h>
  #include <pthread.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>

  #define THREAD_COUNT 1000
  char *filename;
  void *worker(void *p)
  {
        void *ptr;
        int fd;
        char *pptr;

        fd = open(filename, O_RDONLY);
        if (fd < 0)
                return NULL;
        while (1) {
                struct timespec ts = {0, 1000 + rand() % 2000};

                ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0);
                usleep(1);
                if (ptr == MAP_FAILED) {
                        printf("failed to mmap\n");
                        break;
                }
                munmap(ptr, 4096 * 64);
                usleep(1);
                pptr = malloc(1);
                usleep(1);
                pptr[0] = 1;
                usleep(1);
                free(pptr);
                usleep(1);
                nanosleep(&ts, NULL);
        }
        close(fd);
        return NULL;
  }

  int main(int argc, char *argv[])
  {
        void *ptr;
        int i;
        pthread_t threads[THREAD_COUNT];

        if (argc < 2)
                return 0;

        filename = argv[1];

        for (i = 0; i < THREAD_COUNT; i++) {
                if (pthread_create(threads + i, NULL, worker, NULL)) {
                        fprintf(stderr, "Error creating thread\n");
                        return 0;
                }
        }

        for (i = 0; i < THREAD_COUNT; i++)
                pthread_join(threads[i], NULL);
        return 0;
  }
and the following command:
  1. run `stress_test /bin/ls` in one windown
  2. hack bcc trace.py with the following change:
     --- a/tools/trace.py
     +++ b/tools/trace.py
     @@ -513,6 +513,7 @@ BPF_PERF_OUTPUT(%s);
              __data.tgid = __tgid;
              __data.pid = __pid;
              bpf_get_current_comm(&__data.comm, sizeof(__data.comm));
     +        bpf_send_signal(10);
      %s
      %s
              %s.perf_submit(%s, &__data, sizeof(__data));
  3. in a different window run
     ./trace.py -p $(pidof stress_test) t:sched:sched_switch

The deadlock can be reproduced in our production system.

Similar to Song's fix, the fix is to delay sending signal if
irqs is disabled to avoid deadlocks involving with rq_lock.
With this change, my above stress-test in our production system
won't cause deadlock any more.

I also implemented a scale-down version of reproducer in the
selftest (a subsequent commit). With latest bpf-next,
it complains for the following potential deadlock.
  [   32.832450] -> #1 (&p->pi_lock){-.-.}:
  [   32.833100]        _raw_spin_lock_irqsave+0x44/0x80
  [   32.833696]        task_rq_lock+0x2c/0xa0
  [   32.834182]        task_sched_runtime+0x59/0xd0
  [   32.834721]        thread_group_cputime+0x250/0x270
  [   32.835304]        thread_group_cputime_adjusted+0x2e/0x70
  [   32.835959]        do_task_stat+0x8a7/0xb80
  [   32.836461]        proc_single_show+0x51/0xb0
  ...
  [   32.839512] -> #0 (&(&sighand->siglock)->rlock){....}:
  [   32.840275]        __lock_acquire+0x1358/0x1a20
  [   32.840826]        lock_acquire+0xc7/0x1d0
  [   32.841309]        _raw_spin_lock_irqsave+0x44/0x80
  [   32.841916]        __lock_task_sighand+0x79/0x160
  [   32.842465]        do_send_sig_info+0x35/0x90
  [   32.842977]        bpf_send_signal+0xa/0x10
  [   32.843464]        bpf_prog_bc13ed9e4d3163e3_send_signal_tp_sched+0x465/0x1000
  [   32.844301]        trace_call_bpf+0x115/0x270
  [   32.844809]        perf_trace_run_bpf_submit+0x4a/0xc0
  [   32.845411]        perf_trace_sched_switch+0x10f/0x180
  [   32.846014]        __schedule+0x45d/0x880
  [   32.846483]        schedule+0x5f/0xd0
  ...

  [   32.853148] Chain exists of:
  [   32.853148]   &(&sighand->siglock)->rlock --> &p->pi_lock --> &rq->lock
  [   32.853148]
  [   32.854451]  Possible unsafe locking scenario:
  [   32.854451]
  [   32.855173]        CPU0                    CPU1
  [   32.855745]        ----                    ----
  [   32.856278]   lock(&rq->lock);
  [   32.856671]                                lock(&p->pi_lock);
  [   32.857332]                                lock(&rq->lock);
  [   32.857999]   lock(&(&sighand->siglock)->rlock);

  Deadlock happens on CPU0 when it tries to acquire &sighand->siglock
  but it has been held by CPU1 and CPU1 tries to grab &rq->lock
  and cannot get it.

  This is not exactly the callstack in our production environment,
  but sympotom is similar and both locks are using spin_lock_irqsave()
  to acquire the lock, and both involves rq_lock. The fix to delay
  sending signal when irq is disabled also fixed this issue.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200304191104.2796501-1-yhs@fb.com
jenkins-tessares pushed a commit that referenced this issue Apr 1, 2020
Florian Fainelli says:

====================
net: dsa: b53 & bcm_sf2 updates for 7278

This patch series contains some updates to the b53 and bcm_sf2 drivers
specifically for the 7278 Ethernet switch.

The first patch is technically a bug fix so it should ideally be
backported to -stable, provided that Dan also agress with my resolution
on this.

Patches #2 through #4 are minor changes to the core b53 driver to
restore VLAN configuration upon system resumption as well as deny
specific bridge/VLAN operations on port 7 with the 7278 which is special
and does not support VLANs.

Patches #5 through #9 add support for matching VLAN TCI keys/masks to
the CFP code.

Changes in v2:

- fixed some code comments and arrange some code for easier reading
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
jenkins-tessares pushed a commit that referenced this issue Apr 1, 2020
Phy for slot 0 and 1 is shared and handled properly in slot 0.
If there is only one port in use,(slot 0) we shall not call the
'phy_power_off' function with an invalid slot because kernel
will crash with an unaligned access fault like the following:

mt7621-pci 1e140000.pcie: Error applying setting, reverse things back
mt7621-pci-phy 1e149000.pcie-phy: PHY for 0xbe149000 (dual port = 1)
mt7621-pci-phy 1e14a000.pcie-phy: PHY for 0xbe14a000 (dual port = 0)
mt7621-pci-phy 1e149000.pcie-phy: Xtal is 40MHz
mt7621-pci-phy 1e14a000.pcie-phy: Xtal is 40MHz
mt7621-pci 1e140000.pcie: pcie1 no card, disable it (RST & CLK)
Unhandled kernel unaligned access[#1]:
CPU: 3 PID: 111 Comm: kworker/3:2 Not tainted 5.6.0-rc3-00347-g825c6f470c62-dirty #9
Workqueue: events deferred_probe_work_func
$ 0   : 00000000 00000001 5f60d043 8fe1ba80
$ 4   : 0000010d 01eb9000 00000000 00000000
$ 8   : 294b4c00 80940000 00000008 000000ce
$12   : 2e303030 00000000 00000000 65696370
$16   : ffffffed 0000010d 8e373cd0 8214c1e0
$20   : 00000000 82144c80 82144680 8214c250
$24   : 00000018 803ef8f4
$28   : 8e372000 8e373c60 8214c080 803940e8
Hi    : 00000125
Lo    : 122f2000
epc   : 807b3328 mutex_lock+0x8/0x44
ra    : 803940e8 phy_power_off+0x28/0xb0
Status: 1100fc03        KERNEL EXL IE
Cause : 00800010 (ExcCode 04)
BadVA : 0000010d
PrId  : 0001992f (MIPS 1004Kc)
Modules linked in:
Process kworker/3:2 (pid: 111, threadinfo=(ptrval), task=(ptrval), tls=00000000)
Stack : 8e373cd0 803fe4f4 8e372000 8e373c90 8214c080 804fde1c 8e373c98 808d62f4
         8e373c78 00000000 8214c254 804fe648 1e160000 804f27b8 00000001 808d62f4
         00000000 00000001 8214c228 808d62f4 80930000 809a0000 8fd47e10 808d63d4
         808d62d4 8fd47e10 808d0000 808d0000 8e373cd0 8e373cd0 809e2a74 809db510
         809db510 00000006 00000001 00000000 00000000 00000000 01000000 1e1440ff
         ...
Call Trace:
[<807b3328>] mutex_lock+0x8/0x44
[<803940e8>] phy_power_off+0x28/0xb0
[<804fe648>] mt7621_pci_probe+0xc20/0xd18
[<80402ab8>] platform_drv_probe+0x40/0x94
[<80400a74>] really_probe+0x104/0x364
[<803feb74>] bus_for_each_drv+0x84/0xdc
[<80400924>] __device_attach+0xdc/0x120
[<803ffb5c>] bus_probe_device+0xa0/0xbc
[<80400124>] deferred_probe_work_func+0x7c/0xbc
[<800420e8>] process_one_work+0x230/0x450
[<80042638>] worker_thread+0x330/0x5fc
[<80048eb0>] kthread+0x12c/0x134
[<80007438>] ret_from_kernel_thread+0x14/0x1c
Code: 24050002  27bdfff8  8f830000 <c0850000> 14a00005  00000000  00600825  e0810000  1020fffa

Fixes: bf516f4 ("staging: mt7621-pci: use only two phys from device tree")
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20200320153837.20415-1-sergio.paracuellos@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jenkins-tessares pushed a commit that referenced this issue Apr 17, 2020
Fix tcon use-after-free and NULL ptr deref.

Customer system crashes with the following kernel log:

[462233.169868] CIFS VFS: Cancelling wait for mid 4894753 cmd: 14       => a QUERY DIR
[462233.228045] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.305922] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.306205] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347060] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347107] CIFS VFS: Close unmatched open
[462233.347113] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
...
    [exception RIP: cifs_put_tcon+0xa0] (this is doing tcon->ses->server)
 #6 [...] smb2_cancelled_close_fid at ... [cifs]
 #7 [...] process_one_work at ...
 #8 [...] worker_thread at ...
 #9 [...] kthread at ...

The most likely explanation we have is:

* When we put the last reference of a tcon (refcount=0), we close the
  cached share root handle.
* If closing a handle is interrupted, SMB2_close() will
  queue a SMB2_close() in a work thread.
* The queued object keeps a tcon ref so we bump the tcon
  refcount, jumping from 0 to 1.
* We reach the end of cifs_put_tcon(), we free the tcon object despite
  it now having a refcount of 1.
* The queued work now runs, but the tcon, ses & server was freed in
  the meantime resulting in a crash.

THREAD 1
========
cifs_put_tcon                 => tcon refcount reach 0
  SMB2_tdis
   close_shroot_lease
    close_shroot_lease_locked => if cached root has lease && refcount = 0
     smb2_close_cached_fid    => if cached root valid
      SMB2_close              => retry close in a thread if interrupted
       smb2_handle_cancelled_close
        __smb2_handle_cancelled_close    => !! tcon refcount bump 0 => 1 !!
         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
         queue_work(cifsiod_wq, &cancelled->work) => queue work
 tconInfoFree(tcon);    ==> freed!
 cifs_put_smb_ses(ses); ==> freed!

THREAD 2 (workqueue)
========
smb2_cancelled_close_fid
  SMB2_close(0, cancelled->tcon, ...); => use-after-free of tcon
  cifs_put_tcon(cancelled->tcon);      => tcon refcount reach 0 second time
  *CRASH*

Fixes: d919131 ("CIFS: Close cached root handle only if it has a lease")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
pabeni pushed a commit to pabeni/mptcp that referenced this issue Apr 17, 2020
…it/close

Following tool (replicated from syzkaller generated code) generates
warning: "IPv4: Attempt to release TCP socket in state 1".

int main(void) {
        struct sockaddr_in sin1 = { .sin_family = 2, .sin_port = 0x4e20, .sin_addr.s_addr = 0x010000e0, };
        struct sockaddr_in sin2 = { .sin_family = 2, .sin_port = 0x0, .sin_addr.s_addr = 0x0100007f, };
        struct sockaddr_in sin3 = { .sin_family = 2, .sin_port = 0x4e20, .sin_addr.s_addr = 0x0100007f, };
        int r0 = socket(0x2, 0x1, 0x106);
        int r1 = socket(0x2, 0x1, 0x106);

        bind(r1, (void *)&sin1, sizeof(sin1));
        connect(r1, (void *)&sin2, sizeof(sin2));
        listen(r1, 3);
        return connect(r0, (void *)&sin3, 0x4d);
}

Reason is that the newly generated mptcp socket is closed via
the ulp release of the tcp socket, via the listeners accept backlog
purge.
To fix this, delay setting the ESTABLISHED state until after
userspace calls accept and via mptcp specific destructor.

Fixes: 58b0991 ("mptcp: create msk early")
Closes: multipath-tcp/mptcp_net-next#9
Signed-off-by: Florian Westphal <fw@strlen.de>
@pabeni
Copy link
Author

pabeni commented Apr 23, 2020

The issue with stack trace reported above is fixed by upstream commit:

df1036d

But I'm still hitting the warn message with a different stack trace:

[  473.935207] IPv4: Attempt to release TCP socket in state 1 00000000e32b8b7e
[  473.939298] CPU: 1 PID: 6470 Comm: repro Not tainted 5.7.0-rc1.mptcp_3406c7fa5775+ #85
[  473.941191] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014
[  473.965780] Call Trace:
[  473.967752]  <IRQ>
[  473.976341] dump_stack (/home/pabeni/devel/linux-mptcp/lib/dump_stack.c:120)
[  473.980188] __sk_destruct (/home/pabeni/devel/linux-mptcp/./include/linux/compiler.h:199 (discriminator 1) /home/pabeni/devel/linux-mptcp/net/core/sock.c:1698 (discriminator 1))
[  473.981238] subflow_ulp_release (/home/pabeni/devel/linux-mptcp/./include/net/sock.h:1778 /home/pabeni/devel/linux-mptcp/net/mptcp/subflow.c:1120)
[  473.986470] tcp_cleanup_ulp (/home/pabeni/devel/linux-mptcp/net/ipv4/tcp_ulp.c:124)
[  473.987506] tcp_v4_destroy_sock (/home/pabeni/devel/linux-mptcp/net/ipv4/tcp_ipv4.c:2164)
[  473.992193] inet_csk_destroy_sock (/home/pabeni/devel/linux-mptcp/net/ipv4/inet_connection_sock.c:878 (discriminator 9))
[  473.993215] tcp_reset (/home/pabeni/devel/linux-mptcp/./include/asm-generic/bitops/instrumented-non-atomic.h:110 /home/pabeni/devel/linux-mptcp/./include/net/sock.h:884 /home/pabeni/devel/linux-mptcp/net/ipv4/tcp_input.c:4137)
[  473.994024] tcp_validate_incoming (/home/pabeni/devel/linux-mptcp/net/ipv4/tcp_input.c:5470)
[  473.995184] tcp_rcv_state_process (/home/pabeni/devel/linux-mptcp/net/ipv4/tcp_input.c:6232)
[  474.006715] tcp_v4_do_rcv (/home/pabeni/devel/linux-mptcp/net/ipv4/tcp_ipv4.c:1643)
[  474.009066] tcp_v4_rcv (/home/pabeni/devel/linux-mptcp/./include/linux/spinlock.h:393 /home/pabeni/devel/linux-mptcp/net/ipv4/tcp_ipv4.c:2009)
[  474.019255] ip_protocol_deliver_rcu (/home/pabeni/devel/linux-mptcp/net/ipv4/ip_input.c:204 (discriminator 1))
[  474.020764] ip_local_deliver_finish (/home/pabeni/devel/linux-mptcp/./include/linux/rcupdate.h:651 /home/pabeni/devel/linux-mptcp/net/ipv4/ip_input.c:232)
[  474.022248] ip_local_deliver (/home/pabeni/devel/linux-mptcp/./include/linux/netfilter.h:307 /home/pabeni/devel/linux-mptcp/./include/linux/netfilter.h:301 /home/pabeni/devel/linux-mptcp/net/ipv4/ip_input.c:252)
[  474.031541] ip_rcv (/home/pabeni/devel/linux-mptcp/./include/linux/netfilter.h:307 /home/pabeni/devel/linux-mptcp/./include/linux/netfilter.h:301 /home/pabeni/devel/linux-mptcp/net/ipv4/ip_input.c:539)
[  474.045337] __netif_receive_skb_one_core (/home/pabeni/devel/linux-mptcp/net/core/dev.c:5188 (discriminator 4))
[  474.061073] process_backlog (/home/pabeni/devel/linux-mptcp/./include/linux/rcupdate.h:651 /home/pabeni/devel/linux-mptcp/net/core/dev.c:6135)
[  474.070095] net_rx_action (/home/pabeni/devel/linux-mptcp/net/core/dev.c:6572 /home/pabeni/devel/linux-mptcp/net/core/dev.c:6640)
[  474.088098] __do_softirq (/home/pabeni/devel/linux-mptcp/./arch/x86/include/asm/jump_label.h:25 /home/pabeni/devel/linux-mptcp/./include/linux/jump_label.h:200 /home/pabeni/devel/linux-mptcp/./include/trace/events/irq.h:142 /home/pabeni/devel/linux-mptcp/kernel/softirq.c:293)
[  474.092101] do_softirq_own_stack (/home/pabeni/devel/linux-mptcp/arch/x86/entry/entry_64.S:1083)
[  474.093820]  </IRQ>
[  474.100718] do_softirq.part.0 (/home/pabeni/devel/linux-mptcp/kernel/softirq.c:337)
[  474.104535] __local_bh_enable_ip (/home/pabeni/devel/linux-mptcp/./arch/x86/include/asm/preempt.h:26 /home/pabeni/devel/linux-mptcp/kernel/softirq.c:189)
[  474.110930] inet_csk_listen_stop (/home/pabeni/devel/linux-mptcp/./include/asm-generic/atomic-instrumented.h:199 /home/pabeni/devel/linux-mptcp/./include/linux/refcount.h:266 /home/pabeni/devel/linux-mptcp/./include/linux/refcount.h:294 /home/pabeni/devel/linux-mptcp/./include/net/sock.h:1777 /home/pabeni/devel/linux-mptcp/net/ipv4/inet_connection_sock.c:1034)
[  474.112767] tcp_close (/home/pabeni/devel/linux-mptcp/net/ipv4/tcp.c:2355)
[  474.113536] inet_release (/home/pabeni/devel/linux-mptcp/net/ipv4/af_inet.c:429)
[  474.119945] __sock_release (/home/pabeni/devel/linux-mptcp/net/socket.c:606)
[  474.127775] mptcp_close (/home/pabeni/devel/linux-mptcp/net/mptcp/protocol.c:1287)
[  474.139277] inet_release (/home/pabeni/devel/linux-mptcp/net/ipv4/af_inet.c:429)
[  474.142805] __sock_release (/home/pabeni/devel/linux-mptcp/net/socket.c:606)
[  474.146625] sock_close (/home/pabeni/devel/linux-mptcp/net/socket.c:1285)
[  474.148927] __fput (/home/pabeni/devel/linux-mptcp/fs/file_table.c:280)
[  474.152196] task_work_run (/home/pabeni/devel/linux-mptcp/kernel/task_work.c:125 (discriminator 1))
[  474.154412] exit_to_usermode_loop (/home/pabeni/devel/linux-mptcp/./include/linux/tracehook.h:188 /home/pabeni/devel/linux-mptcp/arch/x86/entry/common.c:165)

this looks related to issue#8

@pabeni
Copy link
Author

pabeni commented Apr 24, 2020

The latter splat is really caused by issue#8, will be handled there. Closing this one as fixed by commit df1036d

@pabeni pabeni closed this as completed Apr 24, 2020
jenkins-tessares pushed a commit that referenced this issue May 1, 2020
Ido Schimmel says:

====================
mlxsw: Prepare SPAN API for upcoming changes

Switched port analyzer (SPAN) is used for packet mirroring. Over mlxsw
this is achieved by attaching tc-mirred action to either matchall or
flower classifier.

The current API used to configure SPAN consists of two functions:
mlxsw_sp_span_mirror_add() and mlxsw_sp_span_mirror_del().

These two functions pack a lot of different operations:

* SPAN agent configuration: Determining the egress port and optional
  headers that need to encapsulate the mirrored packet (when mirroring
  to a gretap, for example)

* Egress mirror buffer configuration: Allocating / freeing a buffer when
  port is analyzed (inspected) at egress

* SPAN agent binding: Binding the SPAN agent to a trigger, if any. The
  current triggers are incoming / outgoing packet and they are only used
  for matchall-based mirroring

This non-modular design makes it difficult to extend the API for future
changes, such as new mirror targets (CPU) and new global triggers (early
dropped packets, for example).

Therefore, this patch set gradually adds APIs for above mentioned
operations and then converts the two existing users to use it instead of
the old API. No functional changes intended. Tested with existing
mirroring selftests.

Patch set overview:

Patches #1-#5 gradually add the new API
Patches #6-#8 convert existing users to use the new API
Patch #9 removes the old API
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
jenkins-tessares pushed a commit that referenced this issue May 14, 2020
Martin Blumenstingl says:

====================
dwmac-meson8b Ethernet RX delay configuration

The Ethernet TX performance has been historically bad on Meson8b and
Meson8m2 SoCs because high packet loss was seen. I found out that this
was related (yet again) to the RGMII TX delay configuration.
In the process of discussing the big picture (and not just a single
patch) [0] with Andrew I discovered that the IP block behind the
dwmac-meson8b driver actually seems to support the configuration of the
RGMII RX delay (at least on the Meson8b SoC generation).

Since I sent the first RFC I got additional documentation from Jianxin
(many thanks!). Also I have discovered some more interesting details:
- Meson8b Odroid-C1 requires an RX delay (by either the PHY or the MAC)
  Based on the vendor u-boot code (not upstream) I assume that it will
  be the same for all Meson8b and Meson8m2 boards
- Khadas VIM2 seems to have the RX delay built into the PCB trace
  length. When I enable the RX delay on the PHY or MAC I can't get any
  data through. I expect that we will have the same situation on all
  GXBB, GXM, AXG, G12A, G12B and SM1 boards. Further clarification is
  needed here though (since I can't visually see these lengthened
  traces on the PCB). This will be done before sending patches for
  these boards.

Dependencies for this series:
There is a soft dependency for patch #2 on commit f225314
"dt-bindings: net: dwmac: increase 'maxItems' for 'clocks',
'clock-names' properties" which is currently in Rob's -next tree.
That commit is needed to make the dt-bindings schema validation
pass for patch #2. That patch has been for ~4 weeks in Robs tree,
so I assume that is not going to be dropped.

Changes since RFC v2 at [2]:
- dropped $ref: /schemas/types.yaml#definitions/uint32 from the
  "amlogic,rx-delay-ns" in patch #1 ("Don't need to define the
  type when in standard units." says Rob - thanks, I learned
  something new). Also use "default: 0" for for this property
  instead of explaining it in the description text.
- added a note to the cover-letter about a hidden dependency for
  dt-binding schema validation in patch #2
- Added Andrew's Reviewed-by to patches 1-7. Thank you again for
  the quick and detailed reviews, I appreciate this!
- error out if the (optional) timing-adjustment clock is missing
  but we're asked to enable the RGMII RX delay. The MAC won't
  work in this specific case and either the RX delay has to be
  provided by the PHY or the timing-adjustment clock has to be
  added.
- dropped the dts patches (#9-11) which were only added to give
  an overview how this is going to be used. those will be sent
  separately
- dropped the RFC prefix

Changes since RFC v1 at [1]:
- add support for the timing adjustment clock input (dt-bindings and
  in the driver) thanks to the input from the unnamed Ethernet engineer
  at Amlogic. This is the missing link between the fclk_div2 clock and
  the Ethernet controller on Meson8b (no traffic would flow if that
  clock was disabled)
- add support fot the amlogic,rx-delay-ns property. The only supported
  values so far are 0ns and 2ns. The registers seem to allow more
  precise timing adjustments, but I could not make that work so far.
- add more register documentation (for the new RX delay bits) and
  unified the placement of existing register documentation. Again,
  thanks to Jianxin and the unnamed Ethernet engineer at Amlogic
- DO NOT MERGE: .dts patches to show the conversion of the Meson8b
  and Meson8m2 boards to "rgmii-id". I didn't have time for all arm64
  patches yet, but these will switch to phy-mode = "rgmii-txid" with
  amlogic,rx-delay-ns = <0> (because the delay seems to be provided by
  the PCB trace length).

[0] https://patchwork.kernel.org/patch/11309891/
[1] https://patchwork.kernel.org/cover/11310719/
[2] https://patchwork.kernel.org/cover/11518257/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
jenkins-tessares pushed a commit that referenced this issue May 25, 2020
This BUG halt was reported a while back, but the patch somehow got
missed:

PID: 2879   TASK: c16adaa0  CPU: 1   COMMAND: "sctpn"
 #0 [f418dd28] crash_kexec at c04a7d8c
 #1 [f418dd7c] oops_end at c0863e02
 #2 [f418dd90] do_invalid_op at c040aaca
 #3 [f418de28] error_code (via invalid_op) at c08631a5
    EAX: f34baac0  EBX: 00000090  ECX: f418deb0  EDX: f5542950  EBP: 00000000
    DS:  007b      ESI: f34ba800  ES:  007b      EDI: f418dea0  GS:  00e0
    CS:  0060      EIP: c046fa5e  ERR: ffffffff  EFLAGS: 00010286
 #4 [f418de5c] add_timer at c046fa5e
 #5 [f418de68] sctp_do_sm at f8db8c77 [sctp]
 #6 [f418df30] sctp_primitive_SHUTDOWN at f8dcc1b5 [sctp]
 #7 [f418df48] inet_shutdown at c080baf9
 #8 [f418df5c] sys_shutdown at c079eedf
 #9 [f418df70] sys_socketcall at c079fe88
    EAX: ffffffda  EBX: 0000000d  ECX: bfceea90  EDX: 0937af98
    DS:  007b      ESI: 0000000c  ES:  007b      EDI: b7150ae4
    SS:  007b      ESP: bfceea7c  EBP: bfceeaa8  GS:  0033
    CS:  0073      EIP: b775c424  ERR: 00000066  EFLAGS: 00000282

It appears that the side effect that starts the shutdown timer was processed
multiple times, which can happen as multiple paths can trigger it.  This of
course leads to the BUG halt in add_timer getting called.

Fix seems pretty straightforward, just check before the timer is added if its
already been started.  If it has mod the timer instead to min(current
expiration, new expiration)

Its been tested but not confirmed to fix the problem, as the issue has only
occured in production environments where test kernels are enjoined from being
installed.  It appears to be a sane fix to me though.  Also, recentely,
Jere found a reproducer posted on list to confirm that this resolves the
issues

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: jere.leppanen@nokia.com
CC: marcelo.leitner@gmail.com
CC: netdev@vger.kernel.org
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue Jun 2, 2020
Ido Schimmel says:

====================
devlink: Add support for control packet traps

So far device drivers were only able to register drop and exception
packet traps with devlink. These traps are used for packets that were
either dropped by the underlying device or encountered an exception
(e.g., missing neighbour entry) during forwarding.

However, in the steady state, the majority of the packets being trapped
to the CPU are packets that are required for the correct functioning of
the control plane. For example, ARP request and IGMP query packets.

This patch set allows device drivers to register such control traps with
devlink and expose their default control plane policy to user space.
User space can then tune the packet trap policer settings according to
its needs, as with existing packet traps.

In a similar fashion to exception traps, the action associated with such
traps cannot be changed as it can easily break the control plane. Unlike
drop and exception traps, packets trapped via control traps are not
reported to the kernel's drop monitor as they are not indicative of any
problem.

Patch set overview:

Patches #1-#3 break out layer 3 exceptions to a different group to
provide better granularity. A future patch set will make this completely
configurable.

Patch #4 adds a new trap action ('mirror') that is used for packets that
are forwarded by the device and sent to the CPU. Such packets are marked
by device drivers with 'skb->offload_fwd_mark = 1' in order to prevent
the kernel from forwarding them again.

Patch #5 adds the new trap type, 'control'.

Patches #6-#8 gradually add various control traps to devlink with proper
documentation.

Patch #9 adds a few control traps to netdevsim, which are automatically
exercised by existing devlink-trap selftest.

Patches #10 performs small refactoring in mlxsw.

Patches #11-#13 change mlxsw to register its existing control traps with
devlink.

Patch #14 adds a selftest over mlxsw that exercises all the registered
control traps.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
jenkins-tessares pushed a commit that referenced this issue Jun 9, 2020
Implement rtas_call_reentrant() for reentrant rtas-calls:
"ibm,int-on", "ibm,int-off",ibm,get-xive" and  "ibm,set-xive".

On LoPAPR Version 1.1 (March 24, 2016), from 7.3.10.1 to 7.3.10.4,
items 2 and 3 say:

2 - For the PowerPC External Interrupt option: The * call must be
reentrant to the number of processors on the platform.
3 - For the PowerPC External Interrupt option: The * argument call
buffer for each simultaneous call must be physically unique.

So, these rtas-calls can be called in a lockless way, if using
a different buffer for each cpu doing such rtas call.

For this, it was suggested to add the buffer (struct rtas_args)
in the PACA struct, so each cpu can have it's own buffer.
The PACA struct received a pointer to rtas buffer, which is
allocated in the memory range available to rtas 32-bit.

Reentrant rtas calls are useful to avoid deadlocks in crashing,
where rtas-calls are needed, but some other thread crashed holding
the rtas.lock.

This is a backtrace of a deadlock from a kdump testing environment:

  #0 arch_spin_lock
  #1  lock_rtas ()
  #2  rtas_call (token=8204, nargs=1, nret=1, outputs=0x0)
  #3  ics_rtas_mask_real_irq (hw_irq=4100)
  #4  machine_kexec_mask_interrupts
  #5  default_machine_crash_shutdown
  #6  machine_crash_shutdown
  #7  __crash_kexec
  #8  crash_kexec
  #9  oops_end

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
[mpe: Move under #ifdef PSERIES to avoid build breakage]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200518234245.200672-3-leobras.c@gmail.com
jenkins-tessares pushed a commit that referenced this issue Jun 9, 2020
A misbehaving qemu created a situation where the ACPI SRAT table
advertised one fewer proximity domains than intended.  The NFIT table did
describe all the expected proximity domains.  This caused the device dax
driver to assign an impossible target_node to the device, and when
hotplugged as system memory, this would fail with the following signature:

   BUG: kernel NULL pointer dereference, address: 0000000000000088
   #PF: supervisor read access in kernel mode
   #PF: error_code(0x0000) - not-present page
   PGD 80000001767d4067 P4D 80000001767d4067 PUD 10e0c4067 PMD 0
   Oops: 0000 [#1] SMP PTI
   CPU: 4 PID: 22737 Comm: kswapd3 Tainted: G           O      5.6.0-rc5 #9
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
   RIP: 0010:prepare_kswapd_sleep+0x7c/0xc0
   Code: 89 df e8 87 fd ff ff 89 c2 31 c0 84 d2 74 e6 0f 1f 44 00 00 48 8b 05 fb af 7a 01 48 63 93 88 1d 01 00 48 8b 84 d0 20 0f 00 00 <48> 3b 98 88 00 00 00 75 28 f0 80 a0 80 00 00 00 fe f0 80 a3 38 20
   RSP: 0018:ffffc900017a3e78 EFLAGS: 00010202
   RAX: 0000000000000000 RBX: ffff8881209e0000 RCX: 0000000000000000
   RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8881209e0e80
   RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000008000
   R10: 0000000000000000 R11: 0000000000000003 R12: 0000000000000003
   R13: 0000000000000003 R14: 0000000000000000 R15: ffffc900017a3ec8
   FS:  0000000000000000(0000) GS:ffff888318c00000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 0000000000000088 CR3: 0000000120b50002 CR4: 00000000001606e0
   Call Trace:
    kswapd+0x103/0x520
    kthread+0x120/0x140
    ret_from_fork+0x3a/0x50

Add a check in the add_memory path to fail if the node to which we are
adding memory is in the node_possible_map

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20200416225438.15208-1-vishal.l.verma@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
matttbe pushed a commit that referenced this issue Jun 15, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 15, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 16, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 16, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 18, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 19, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 19, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 20, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 21, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 22, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 23, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 24, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 24, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 25, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 26, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Jun 26, 2020
when a MPTCP client tries to connect to itself, tcp_finish_connect() is
never reached. Because of this, depending on the socket current state,
multiple faulty behaviours can be observed:

1) a WARN_ON() in subflow_data_ready() is hit
 WARNING: CPU: 2 PID: 882 at net/mptcp/subflow.c:911 subflow_data_ready+0x18b/0x230
 [...]
 CPU: 2 PID: 882 Comm: gh35 Not tainted 5.7.0+ #187
 [...]
 RIP: 0010:subflow_data_ready+0x18b/0x230
 [...]
 Call Trace:
  tcp_data_queue+0xd2f/0x4250
  tcp_rcv_state_process+0xb1c/0x49d3
  tcp_v4_do_rcv+0x2bc/0x790
  __release_sock+0x153/0x2d0
  release_sock+0x4f/0x170
  mptcp_shutdown+0x167/0x4e0
  __sys_shutdown+0xe6/0x180
  __x64_sys_shutdown+0x50/0x70
  do_syscall_64+0x9a/0x370
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

2) client is stuck forever in mptcp_sendmsg() because the socket is not
   TCP_ESTABLISHED

 crash> bt 4847
 PID: 4847   TASK: ffff88814b2fb100  CPU: 1   COMMAND: "gh35"
  #0 [ffff8881376ff680] __schedule at ffffffff97248da4
  #1 [ffff8881376ff778] schedule at ffffffff9724a34f
  #2 [ffff8881376ff7a0] schedule_timeout at ffffffff97252ba0
  #3 [ffff8881376ff8a8] wait_woken at ffffffff958ab4ba
  #4 [ffff8881376ff940] sk_stream_wait_connect at ffffffff96c2d859
  #5 [ffff8881376ffa28] mptcp_sendmsg at ffffffff97207fca
  #6 [ffff8881376ffbc0] sock_sendmsg at ffffffff96be1b5b
  #7 [ffff8881376ffbe8] sock_write_iter at ffffffff96be1daa
  #8 [ffff8881376ffce8] new_sync_write at ffffffff95e5cb52
  #9 [ffff8881376ffe50] vfs_write at ffffffff95e6547f
 #10 [ffff8881376ffe90] ksys_write at ffffffff95e65d26
 #11 [ffff8881376fff28] do_syscall_64 at ffffffff956088ba
 #12 [ffff8881376fff50] entry_SYSCALL_64_after_hwframe at ffffffff9740008c
     RIP: 00007f126f6956ed  RSP: 00007ffc2a320278  RFLAGS: 00000217
     RAX: ffffffffffffffda  RBX: 0000000020000044  RCX: 00007f126f6956ed
     RDX: 0000000000000004  RSI: 00000000004007b8  RDI: 0000000000000003
     RBP: 00007ffc2a3202a0   R8: 0000000000400720   R9: 0000000000400720
     R10: 0000000000400720  R11: 0000000000000217  R12: 00000000004004b0
     R13: 00007ffc2a320380  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

3) tcpdump captures show that DSS is exchanged even when MP_CAPABLE handshake
   didn't complete.

 $ tcpdump -tnnr bad.pcap
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S], seq 3208913911, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291694721,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [S.], seq 3208913911, ack 3208913912, win 65483, options [mss 65495,sackOK,TS val 3291706876 ecr 3291706876,nop,wscale 7,mptcp capable v1], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 1, win 512, options [nop,nop,TS val 3291706876 ecr 3291706876], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [F.], seq 1, ack 1, win 512, options [nop,nop,TS val 3291707876 ecr 3291706876,mptcp dss fin seq 0 subseq 0 len 1,nop,nop], length 0
 IP 127.0.0.1.20000 > 127.0.0.1.20000: Flags [.], ack 2, win 512, options [nop,nop,TS val 3291707876 ecr 3291707876], length 0

force a fallback to TCP in these cases, and adjust the main socket
state to avoid hanging in mptcp_sendmsg().

Closes: #35
Reported-by: Christoph Paasch <cpaasch@apple.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
matttbe pushed a commit that referenced this issue May 1, 2024
Wen Gu says:

====================
net/smc: SMC intra-OS shortcut with loopback-ism

This patch set acts as the second part of the new version of [1] (The first
part can be referred from [2]), the updated things of this version are listed
at the end.

- Background

SMC-D is now used in IBM z with ISM function to optimize network interconnect
for intra-CPC communications. Inspired by this, we try to make SMC-D available
on the non-s390 architecture through a software-implemented Emulated-ISM device,
that is the loopback-ism device here, to accelerate inter-process or
inter-containers communication within the same OS instance.

- Design

This patch set includes 3 parts:

 - Patch #1: some prepare work for loopback-ism.
 - Patch #2-#7: implement loopback-ism device and adapt SMC-D for it.
   loopback-ism now serves only SMC and no userspace interfaces exposed.
 - Patch #8-#11: memory copy optimization for intra-OS scenario.

The loopback-ism device is designed as an ISMv2 device and not be limited to
a specific net namespace, ends of both inter-process connection (1/1' in diagram
below) or inter-container connection (2/2' in diagram below) can find the same
available loopback-ism and choose it during the CLC handshake.

 Container 1 (ns1)                              Container 2 (ns2)
 +-----------------------------------------+    +-------------------------+
 | +-------+      +-------+      +-------+ |    |        +-------+        |
 | | App A |      | App B |      | App C | |    |        | App D |<-+     |
 | +-------+      +---^---+      +-------+ |    |        +-------+  |(2') |
 |     |127.0.0.1 (1')|             |192.168.0.11       192.168.0.12|     |
 |  (1)|   +--------+ | +--------+  |(2)   |    | +--------+   +--------+ |
 |     `-->|   lo   |-` |  eth0  |<-`      |    | |   lo   |   |  eth0  | |
 +---------+--|---^-+---+-----|--+---------+    +-+--------+---+-^------+-+
              |   |           |                                  |
 Kernel       |   |           |                                  |
 +----+-------v---+-----------v----------------------------------+---+----+
 |    |                            TCP                               |    |
 |    |                                                              |    |
 |    +--------------------------------------------------------------+    |
 |                                                                        |
 |                           +--------------+                             |
 |                           | smc loopback |                             |
 +---------------------------+--------------+-----------------------------+

loopback-ism device creates DMBs (shared memory) for each connection peer.
Since data transfer occurs within the same kernel, the sndbuf of each peer
is only a descriptor and point to the same memory region as peer DMB, so that
the data copy from sndbuf to peer DMB can be avoided in loopback-ism case.

 Container 1 (ns1)                              Container 2 (ns2)
 +-----------------------------------------+    +-------------------------+
 | +-------+                               |    |        +-------+        |
 | | App C |-----+                         |    |        | App D |        |
 | +-------+     |                         |    |        +-^-----+        |
 |               |                         |    |          |              |
 |           (2) |                         |    |     (2') |              |
 |               |                         |    |          |              |
 +---------------|-------------------------+    +----------|--------------+
                 |                                         |
 Kernel          |                                         |
 +---------------|-----------------------------------------|--------------+
 | +--------+ +--v-----+                           +--------+ +--------+  |
 | |dmb_desc| |snd_desc|                           |dmb_desc| |snd_desc|  |
 | +-----|--+ +--|-----+                           +-----|--+ +--------+  |
 | +-----|--+    |                                 +-----|--+             |
 | | DMB C  |    +---------------------------------| DMB D  |             |
 | +--------+                                      +--------+             |
 |                                                                        |
 |                           +--------------+                             |
 |                           | smc loopback |                             |
 +---------------------------+--------------+-----------------------------+

- Benchmark Test

 * Test environments:
      - VM with Intel Xeon Platinum 8 core 2.50GHz, 16 GiB mem.
      - SMC sndbuf/DMB size 1MB.

 * Test object:
      - TCP: run on TCP loopback.
      - SMC lo: run on SMC loopback-ism.

1. ipc-benchmark (see [3])

 - ./<foo> -c 1000000 -s 100

                            TCP                  SMC-lo
Message
rate (msg/s)              84991                  151293(+78.01%)

2. sockperf

 - serv: <smc_run> sockperf sr --tcp
 - clnt: <smc_run> sockperf { tp | pp } --tcp --msg-size={ 64000 for tp | 14 for pp } -i 127.0.0.1 -t 30

                            TCP                  SMC-lo
Bandwidth(MBps)        5033.569                7987.732(+58.69%)
Latency(us)               5.986                   3.398(-43.23%)

3. nginx/wrk

 - serv: <smc_run> nginx
 - clnt: <smc_run> wrk -t 8 -c 1000 -d 30 http://127.0.0.1:80

                           TCP                   SMC-lo
Requests/s           187951.76                267107.90(+42.12%)

4. redis-benchmark

 - serv: <smc_run> redis-server
 - clnt: <smc_run> redis-benchmark -h 127.0.0.1 -q -t set,get -n 400000 -c 200 -d 1024

                           TCP                   SMC-lo
GET(Requests/s)       86132.64                118133.49(+37.15%)
SET(Requests/s)       87374.40                122887.86(+40.65%)

Change log:
v7->v6
- Patch #2: minor: remove unnecessary 'return' of inline smc_loopback_exit().
- Patch #10: minor: directly return 0 instead of 'rc' in smcd_cdc_msg_send().
- all: collect the Reviewed-by tags.

v6->RFC v5
Link: https://lore.kernel.org/netdev/20240414040304.54255-1-guwen@linux.alibaba.com/
- Patch #2: make the use of CONFIG_SMC_LO cleaner.
- Patch #5: mark some smcd_ops that loopback-ism doesn't support as
  optional and check for the support when they are called.
- Patch #7: keep loopback-ism at the beginning of the SMC-D device list.
- Some expression changes in commit logs and comments.

RFC v5->RFC v4:
Link: https://lore.kernel.org/netdev/20240324135522.108564-1-guwen@linux.alibaba.com/
- Patch #2: minor changes in description of config SMC_LO and comments.
- Patch #10: minor changes in comments and if(smc_ism_support_dmb_nocopy())
  check in smcd_cdc_msg_send().
- Patch #3: change smc_lo_generate_id() to smc_lo_generate_ids() and SMC_LO_CHID
  to SMC_LO_RESERVED_CHID.
- Patch #5: memcpy while holding the ldev->dmb_ht_lock.
- Some expression changes in commit logs.

RFC v4->v3:
Link: https://lore.kernel.org/netdev/20240317100545.96663-1-guwen@linux.alibaba.com/
- The merge window of v6.9 is open, so post this series as an RFC.
- Patch #6: since some information fed back by smc_nl_handle_smcd_dev() dose
  not apply to Emulated-ISM (including loopback-ism here), loopback-ism is
  not exposed through smc netlink for the time being. we may refactor this
  part when smc netlink interface is updated.

v3->v2:
Link: https://lore.kernel.org/netdev/20240312142743.41406-1-guwen@linux.alibaba.com/
- Patch #11: use tasklet_schedule(&conn->rx_tsklet) instead of smcd_cdc_rx_handler()
  to avoid possible recursive locking of conn->send_lock and use {read|write}_lock_bh()
  to acquire dmb_ht_lock.

v2->v1:
Link: https://lore.kernel.org/netdev/20240307095536.29648-1-guwen@linux.alibaba.com/
- All the patches: changed the term virtual-ISM to Emulated-ISM as defined by SMCv2.1.
- Patch #3: optimized the description of SMC_LO config. Avoid exposing loopback-ism
  to sysfs and remove all the knobs until future definition clear.
- Patch #3: try to make lockdep happy by using read_lock_bh() in smc_lo_move_data().
- Patch #6: defaultly use physical contiguous DMB buffers.
- Patch #11: defaultly enable DMB no-copy for loopback-ism and free the DMB in
  unregister_dmb or detach_dmb when dmb_node->refcnt reaches 0, instead of using
  wait_event to keep waiting in unregister_dmb.

v1->RFC:
Link: https://lore.kernel.org/netdev/20240111120036.109903-1-guwen@linux.alibaba.com/
- Patch #9: merge rx_bytes and tx_bytes as xfer_bytes statistics:
  /sys/devices/virtual/smc/loopback-ism/xfer_bytes
- Patch #10: add support_dmb_nocopy operation to check if SMC-D device supports
  merging sndbuf with peer DMB.
- Patch #13 & #14: introduce loopback-ism device control of DMB memory type and
  control of whether to merge sndbuf and DMB. They can be respectively set by:
  /sys/devices/virtual/smc/loopback-ism/dmb_type
  /sys/devices/virtual/smc/loopback-ism/dmb_copy
  The motivation for these two control is that a performance bottleneck was
  found when using vzalloced DMB and sndbuf is merged with DMB, and there are
  many CPUs and CONFIG_HARDENED_USERCOPY is set [4]. The bottleneck is caused
  by the lock contention in vmap_area_lock [5] which is involved in memcpy_from_msg()
  or memcpy_to_msg(). Currently, Uladzislau Rezki is working on mitigating the
  vmap lock contention [6]. It has significant effects, but using virtual memory
  still has additional overhead compared to using physical memory.
  So this new version provides controls of dmb_type and dmb_copy to suit
  different scenarios.
- Some minor changes and comments improvements.

RFC->old version([1]):
Link: https://lore.kernel.org/netdev/1702214654-32069-1-git-send-email-guwen@linux.alibaba.com/
- Patch #1: improve the loopback-ism dump, it shows as follows now:
  # smcd d
  FID  Type  PCI-ID        PCHID  InUse  #LGs  PNET-ID
  0000 0     loopback-ism  ffff   No        0
- Patch #3: introduce the smc_ism_set_v2_capable() helper and set
  smc_ism_v2_capable when ISMv2 or virtual ISM is registered,
  regardless of whether there is already a device in smcd device list.
- Patch #3: loopback-ism will be added into /sys/devices/virtual/smc/loopback-ism/.
- Patch #8: introduce the runtime switch /sys/devices/virtual/smc/loopback-ism/active
  to activate or deactivate the loopback-ism.
- Patch #9: introduce the statistics of loopback-ism by
  /sys/devices/virtual/smc/loopback-ism/{{tx|rx}_tytes|dmbs_cnt}.
- Some minor changes and comments improvements.

[1] https://lore.kernel.org/netdev/1695568613-125057-1-git-send-email-guwen@linux.alibaba.com/
[2] https://lore.kernel.org/netdev/20231219142616.80697-1-guwen@linux.alibaba.com/
[3] https://github.com/goldsborough/ipc-bench
[4] https://lore.kernel.org/all/3189e342-c38f-6076-b730-19a6efd732a5@linux.alibaba.com/
[5] https://lore.kernel.org/all/238e63cd-e0e8-4fbf-852f-bc4d5bc35d5a@linux.alibaba.com/
[6] https://lore.kernel.org/all/20240102184633.748113-1-urezki@gmail.com/
====================

Link: https://lore.kernel.org/r/20240428060738.60843-1-guwen@linux.alibaba.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
matttbe pushed a commit that referenced this issue May 13, 2024
…/git/pablo/gtp

Pablo neira Ayuso says:

====================
gtp pull request 24-05-07

This v3 includes:
- fix for clang uninitialized variable per Jakub.
- address Smatch and Coccinelle reports per Simon
- remove inline in new IPv6 support per Simon
- fix memleaks in netlink control plane per Simon
-o-

The following patchset contains IPv6 GTP driver support for net-next,
this also includes IPv6 over IPv4 and vice-versa:

Patch #1 removes a unnecessary stack variable initialization in the
         socket routine.

Patch #2 deals with GTP extension headers. This variable length extension
         header to decapsulate packets accordingly. Otherwise, packets are
         dropped when these extension headers are present which breaks
         interoperation with other non-Linux based GTP implementations.

Patch #3 prepares for IPv6 support by moving IPv4 specific fields in PDP
         context objects to a union.

Patch #4 adds IPv6 support while retaining backward compatibility.
         Three new attributes allows to declare an IPv6 GTP tunnel
         GTPA_FAMILY, GTPA_PEER_ADDR6 and GTPA_MS_ADDR6 as well as
         IFLA_GTP_LOCAL6 to declare the IPv6 GTP UDP socket. Up to this
         patch, only IPv6 outer in IPv6 inner is supported.

Patch #5 uses IPv6 address /64 prefix for UE/MS in the inner headers.
         Unlike IPv4, which provides a 1:1 mapping between UE/MS,
         IPv6 tunnel encapsulates traffic for /64 address as specified
         by 3GPP TS. Patch has been split from Patch #4 to highlight
         this behaviour.

Patch #6 passes up IPv6 link-local traffic, such as IPv6 SLAAC, for
         handling to userspace so they are handled as control packets.

Patch #7 prepares to allow for GTP IPv4 over IPv6 and vice-versa by
         moving IP specific debugging out of the function to build
         IPv4 and IPv6 GTP packets.

Patch #8 generalizes TOS/DSCP handling following similar approach as
         in the existing iptunnel infrastructure.

Patch #9 adds a helper function to build an IPv4 GTP packet in the outer
         header.

Patch #10 adds a helper function to build an IPv6 GTP packet in the outer
          header.

Patch #11 adds support for GTP IPv4-over-IPv6 and vice-versa.

Patch #12 allows to use the same TID/TEID (tunnel identifier) for inner
          IPv4 and IPv6 packets for better UE/MS dual stack integration.

This series integrates with the osmocom.org project CI and TTCN-3 test
infrastructure (Oliver Smith) as well as the userspace libgtpnl library.

Thanks to Harald Welte, Oliver Smith and Pau Espin for reviewing and
providing feedback through the osmocom.org redmine platform to make this
happen.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
Kendrenogen pushed a commit to Kendrenogen/android_kernel_lge_sm8150 that referenced this issue May 21, 2024
…it/close

Following snippet (replicated from syzkaller reproducer) generates
warning: "IPv4: Attempt to release TCP socket in state 1".

int main(void) {
 struct sockaddr_in sin1 = { .sin_family = 2, .sin_port = 0x4e20,
                             .sin_addr.s_addr = 0x010000e0, };
 struct sockaddr_in sin2 = { .sin_family = 2,
	                     .sin_addr.s_addr = 0x0100007f, };
 struct sockaddr_in sin3 = { .sin_family = 2, .sin_port = 0x4e20,
	                     .sin_addr.s_addr = 0x0100007f, };
 int r0 = socket(0x2, 0x1, 0x106);
 int r1 = socket(0x2, 0x1, 0x106);

 bind(r1, (void *)&sin1, sizeof(sin1));
 connect(r1, (void *)&sin2, sizeof(sin2));
 listen(r1, 3);
 return connect(r0, (void *)&sin3, 0x4d);
}

Reason is that the newly generated mptcp socket is closed via the ulp
release of the tcp listener socket when its accept backlog gets purged.

To fix this, delay setting the ESTABLISHED state until after userspace
calls accept and via mptcp specific destructor.

Fixes: 54a0f1d8f6365 ("mptcp: create msk early")
Closes: multipath-tcp/mptcp_net-next#9
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue May 24, 2024
ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240507183545.1236093-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matttbe pushed a commit that referenced this issue Jun 14, 2024
…PLES event"

This reverts commit 7d1405c.

This causes segfaults in some cases, as reported by Milian:

  ```
  sudo /usr/bin/perf record -z --call-graph dwarf -e cycles -e
  raw_syscalls:sys_enter ls
  ...
  [ perf record: Woken up 3 times to write data ]
  malloc(): invalid next size (unsorted)
  Aborted
  ```

  Backtrace with GDB + debuginfod:

  ```
  malloc(): invalid next size (unsorted)

  Thread 1 "perf" received signal SIGABRT, Aborted.
  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6,
  no_tid=no_tid@entry=0) at pthread_kill.c:44
  Downloading source file /usr/src/debug/glibc/glibc/nptl/pthread_kill.c
  44            return INTERNAL_SYSCALL_ERROR_P (ret) ? INTERNAL_SYSCALL_ERRNO
  (ret) : 0;
  (gdb) bt
  #0  __pthread_kill_implementation (threadid=<optimized out>,
  signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
  #1  0x00007ffff6ea8eb3 in __pthread_kill_internal (threadid=<optimized out>,
  signo=6) at pthread_kill.c:78
  #2  0x00007ffff6e50a30 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/
  raise.c:26
  #3  0x00007ffff6e384c3 in __GI_abort () at abort.c:79
  #4  0x00007ffff6e39354 in __libc_message_impl (fmt=fmt@entry=0x7ffff6fc22ea
  "%s\n") at ../sysdeps/posix/libc_fatal.c:132
  #5  0x00007ffff6eb3085 in malloc_printerr (str=str@entry=0x7ffff6fc5850
  "malloc(): invalid next size (unsorted)") at malloc.c:5772
  #6  0x00007ffff6eb657c in _int_malloc (av=av@entry=0x7ffff6ff6ac0
  <main_arena>, bytes=bytes@entry=368) at malloc.c:4081
  #7  0x00007ffff6eb877e in __libc_calloc (n=<optimized out>,
  elem_size=<optimized out>) at malloc.c:3754
  #8  0x000055555569bdb6 in perf_session.do_write_header ()
  #9  0x00005555555a373a in __cmd_record.constprop.0 ()
  #10 0x00005555555a6846 in cmd_record ()
  #11 0x000055555564db7f in run_builtin ()
  #12 0x000055555558ed77 in main ()
  ```

  Valgrind memcheck:
  ```
  ==45136== Invalid write of size 8
  ==45136==    at 0x2B38A5: perf_event__synthesize_id_sample (in /usr/bin/perf)
  ==45136==    by 0x157069: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==  Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd
  ==45136==    at 0x4849BF3: calloc (vg_replace_malloc.c:1675)
  ==45136==    by 0x3574AB: zalloc (in /usr/bin/perf)
  ==45136==    by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==
  ==45136== Syscall param write(buf) points to unaddressable byte(s)
  ==45136==    at 0x575953D: __libc_write (write.c:26)
  ==45136==    by 0x575953D: write (write.c:24)
  ==45136==    by 0x35761F: ion (in /usr/bin/perf)
  ==45136==    by 0x357778: writen (in /usr/bin/perf)
  ==45136==    by 0x1548F7: record__write (in /usr/bin/perf)
  ==45136==    by 0x15708A: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==  Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd
  ==45136==    at 0x4849BF3: calloc (vg_replace_malloc.c:1675)
  ==45136==    by 0x3574AB: zalloc (in /usr/bin/perf)
  ==45136==    by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==
 -----

Closes: https://lore.kernel.org/linux-perf-users/23879991.0LEYPuXRzz@milian-workstation/
Reported-by: Milian Wolff <milian.wolff@kdab.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@kernel.org # 6.8+
Link: https://lore.kernel.org/lkml/Zl9ksOlHJHnKM70p@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
matttbe pushed a commit that referenced this issue Jun 14, 2024
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
matttbe pushed a commit that referenced this issue Jun 28, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Jul 1, 2024
Danielle Ratson says:

====================
Add ability to flash modules' firmware

CMIS compliant modules such as QSFP-DD might be running a firmware that
can be updated in a vendor-neutral way by exchanging messages between
the host and the module as described in section 7.2.2 of revision
4.0 of the CMIS standard.

According to the CMIS standard, the firmware update process is done
using a CDB commands sequence.

CDB (Command Data Block Message Communication) reads and writes are
performed on memory map pages 9Fh-AFh according to the CMIS standard,
section 8.12 of revision 4.0.

Add a pair of new ethtool messages that allow:

* User space to trigger firmware update of transceiver modules

* The kernel to notify user space about the progress of the process

The user interface is designed to be asynchronous in order to avoid RTNL
being held for too long and to allow several modules to be updated
simultaneously. The interface is designed with CMIS compliant modules in
mind, but kept generic enough to accommodate future use cases, if these
arise.

The kernel interface that will implement the firmware update using CDB
command will include 2 layers that will be added under ethtool:

* The upper layer that will be triggered from the module layer, is
 cmis_ fw_update.
* The lower one is cmis_cdb.

In the future there might be more operations to implement using CDB
commands. Therefore, the idea is to keep the cmis_cdb interface clean and
the cmis_fw_update specific to the cdb commands handling it.

The communication between the kernel and the driver will be done using
two ethtool operations that enable reading and writing the transceiver
module EEPROM.
The operation ethtool_ops::get_module_eeprom_by_page, that is already
implemented, will be used for reading from the EEPROM the CDB reply,
e.g. reading module setting, state, etc.
The operation ethtool_ops::set_module_eeprom_by_page, that is added in
the current patchset, will be used for writing to the EEPROM the CDB
command such as start firmware image, run firmware image, etc.

Therefore in order for a driver to implement module flashing, that
driver needs to implement the two functions mentioned above.

Patchset overview:
Patch #1-#2: Implement the EEPROM writing in mlxsw.
Patch #3: Define the interface between the kernel and user space.
Patch #4: Add ability to notify the flashing firmware progress.
Patch #5: Veto operations during flashing.
Patch #6: Add extended compliance codes.
Patch #7: Add the cdb layer.
Patch #8: Add the fw_update layer.
Patch #9: Add ability to flash transceiver modules' firmware.

v8:
	Patch #7:
	* In the ethtool_cmis_wait_for_cond() evaluate the condition once more
	  to decide if the error code should be -ETIMEDOUT or something else.
	* s/netdev_err/netdev_err_once.

v7:
	Patch #4:
		* Return -ENOMEM instead of PTR_ERR(attr) on
		  ethnl_module_fw_flash_ntf_put_err().
	Patch #9:
		* Fix Warning for not unlocking the spin_lock in the error flow
          	  on module_flash_fw_work_list_add().
		* Avoid the fall-through on ethnl_sock_priv_destroy().

v6:
	* Squash some of the last patch to patch #5 and patch #9.
	Patch #3:
		* Add paragraph in .rst file.
	Patch #4:
		* Reserve '1' more place on SKB for NUL terminator in
		  the error message string.
		* Add more prints on error flow, re-write the printing
		  function and add ethnl_module_fw_flash_ntf_put_err().
		* Change the communication method so notification will be
		  sent in unicast instead of multicast.
		* Add new 'struct ethnl_module_fw_flash_ntf_params' that holds
		  the relevant info for unicast communication and use it to
		  send notification to the specific socket.
		* s/nla_put_u64_64bit/nla_put_uint/
	Patch #7:
		* In ethtool_cmis_cdb_init(), Use 'const' for the 'params'
		  parameter.
	Patch #8:
		* Add a list field to struct ethtool_module_fw_flash for
		  module_fw_flash_work_list that will be presented in the next
		  patch.
		* Move ethtool_cmis_fw_update() cleaning to a new function that
		  will be represented in the next patch.
		* Move some of the fields in struct ethtool_module_fw_flash to
		  a separate struct, so ethtool_cmis_fw_update() will get only
		  the relevant parameters for it.
		* Edit the relevant functions to get the relevant params for
		  them.
		* s/CMIS_MODULE_READY_MAX_DURATION_USEC/CMIS_MODULE_READY_MAX_DURATION_MSEC
	Patch #9:
		* Add a paragraph in the commit message.
		* Rename labels in module_flash_fw_schedule().
		* Add info to genl_sk_priv_*() and implement the relevant
		  callbacks, in order to handle properly a scenario of closing
		  the socket from user space before the work item was ended.
		* Add a list the holds all the ethtool_module_fw_flash struct
		  that corresponds to the in progress work items.
		* Add a new enum for the socket types.
		* Use both above to identify a flashing socket, add it to the
		  list and when closing socket affect only the flashing type.
		* Create a new function that will get the work item instead of
		  ethtool_cmis_fw_update().
		* Edit the relevant functions to get the relevant params for
		  them.
		* The new function will call the old ethtool_cmis_fw_update(),
		  and do the cleaning, so the existence of the list should be
		  completely isolated in module.c.
===================

Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue Jul 10, 2024
Since f663a03 ("bpf, x64: Remove tail call detection"),
tail_call_reachable won't be detected in x86 JIT. And, tail_call_reachable
is provided by verifier.

Therefore, in test_bpf, the tail_call_reachable must be provided in test
cases before running.

Fix and test:

[  174.828662] test_bpf: #0 Tail call leaf jited:1 170 PASS
[  174.829574] test_bpf: #1 Tail call 2 jited:1 244 PASS
[  174.830363] test_bpf: #2 Tail call 3 jited:1 296 PASS
[  174.830924] test_bpf: #3 Tail call 4 jited:1 719 PASS
[  174.831863] test_bpf: #4 Tail call load/store leaf jited:1 197 PASS
[  174.832240] test_bpf: #5 Tail call load/store jited:1 326 PASS
[  174.832240] test_bpf: #6 Tail call error path, max count reached jited:1 2214 PASS
[  174.835713] test_bpf: #7 Tail call count preserved across function calls jited:1 609751 PASS
[  175.446098] test_bpf: #8 Tail call error path, NULL target jited:1 472 PASS
[  175.447597] test_bpf: #9 Tail call error path, index out of range jited:1 206 PASS
[  175.448833] test_bpf: test_tail_calls: Summary: 10 PASSED, 0 FAILED, [10/10 JIT'ed]

Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202406251415.c51865bc-oliver.sang@intel.com
Fixes: f663a03 ("bpf, x64: Remove tail call detection")
Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
Link: https://lore.kernel.org/r/20240625145351.40072-1-hffilwlqm@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
matttbe pushed a commit that referenced this issue Jul 12, 2024
Patch series "mm/filemap: Limit page cache size to that supported by
xarray", v2.

Currently, xarray can't support arbitrary page cache size.  More details
can be found from the WARN_ON() statement in xas_split_alloc().  In our
test whose code is attached below, we hit the WARN_ON() on ARM64 system
where the base page size is 64KB and huge page size is 512MB.  The issue
was reported long time ago and some discussions on it can be found here
[1].

[1] https://www.spinics.net/lists/linux-xfs/msg75404.html

In order to fix the issue, we need to adjust MAX_PAGECACHE_ORDER to one
supported by xarray and avoid PMD-sized page cache if needed.  The code
changes are suggested by David Hildenbrand.

PATCH[1] adjusts MAX_PAGECACHE_ORDER to that supported by xarray
PATCH[2-3] avoids PMD-sized page cache in the synchronous readahead path
PATCH[4] avoids PMD-sized page cache for shmem files if needed

Test program
============
# cat test.c
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/syscall.h>
#include <sys/mman.h>

#define TEST_XFS_FILENAME	"/tmp/data"
#define TEST_SHMEM_FILENAME	"/dev/shm/data"
#define TEST_MEM_SIZE		0x20000000

int main(int argc, char **argv)
{
	const char *filename;
	int fd = 0;
	void *buf = (void *)-1, *p;
	int pgsize = getpagesize();
	int ret;

	if (pgsize != 0x10000) {
		fprintf(stderr, "64KB base page size is required\n");
		return -EPERM;
	}

	system("echo force > /sys/kernel/mm/transparent_hugepage/shmem_enabled");
	system("rm -fr /tmp/data");
	system("rm -fr /dev/shm/data");
	system("echo 1 > /proc/sys/vm/drop_caches");

	/* Open xfs or shmem file */
	filename = TEST_XFS_FILENAME;
	if (argc > 1 && !strcmp(argv[1], "shmem"))
		filename = TEST_SHMEM_FILENAME;

	fd = open(filename, O_CREAT | O_RDWR | O_TRUNC);
	if (fd < 0) {
		fprintf(stderr, "Unable to open <%s>\n", filename);
		return -EIO;
	}

	/* Extend file size */
	ret = ftruncate(fd, TEST_MEM_SIZE);
	if (ret) {
		fprintf(stderr, "Error %d to ftruncate()\n", ret);
		goto cleanup;
	}

	/* Create VMA */
	buf = mmap(NULL, TEST_MEM_SIZE,
		   PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
	if (buf == (void *)-1) {
		fprintf(stderr, "Unable to mmap <%s>\n", filename);
		goto cleanup;
	}

	fprintf(stdout, "mapped buffer at 0x%p\n", buf);
	ret = madvise(buf, TEST_MEM_SIZE, MADV_HUGEPAGE);
        if (ret) {
		fprintf(stderr, "Unable to madvise(MADV_HUGEPAGE)\n");
		goto cleanup;
	}

	/* Populate VMA */
	ret = madvise(buf, TEST_MEM_SIZE, MADV_POPULATE_WRITE);
	if (ret) {
		fprintf(stderr, "Error %d to madvise(MADV_POPULATE_WRITE)\n", ret);
		goto cleanup;
	}

	/* Punch the file to enforce xarray split */
	ret = fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
        		TEST_MEM_SIZE - pgsize, pgsize);
	if (ret)
		fprintf(stderr, "Error %d to fallocate()\n", ret);

cleanup:
	if (buf != (void *)-1)
		munmap(buf, TEST_MEM_SIZE);
	if (fd > 0)
		close(fd);

	return 0;
}

# gcc test.c -o test
# cat /proc/1/smaps | grep KernelPageSize | head -n 1
KernelPageSize:       64 kB
# ./test shmem
   :
------------[ cut here ]------------
WARNING: CPU: 17 PID: 5253 at lib/xarray.c:1025 xas_split_alloc+0xf8/0x128
Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib  \
nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct    \
nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4    \
ip_set nf_tables rfkill nfnetlink vfat fat virtio_balloon          \
drm fuse xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64  \
virtio_net sha1_ce net_failover failover virtio_console virtio_blk \
dimlib virtio_mmio
CPU: 17 PID: 5253 Comm: test Kdump: loaded Tainted: G W 6.10.0-rc5-gavin+ #12
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-1.el9 05/24/2024
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : xas_split_alloc+0xf8/0x128
lr : split_huge_page_to_list_to_order+0x1c4/0x720
sp : ffff80008a92f5b0
x29: ffff80008a92f5b0 x28: ffff80008a92f610 x27: ffff80008a92f728
x26: 0000000000000cc0 x25: 000000000000000d x24: ffff0000cf00c858
x23: ffff80008a92f610 x22: ffffffdfc0600000 x21: 0000000000000000
x20: 0000000000000000 x19: ffffffdfc0600000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000018000000000 x15: 3374004000000000
x14: 0000e00000000000 x13: 0000000000002000 x12: 0000000000000020
x11: 3374000000000000 x10: 3374e1c0ffff6000 x9 : ffffb463a84c681c
x8 : 0000000000000003 x7 : 0000000000000000 x6 : ffff00011c976ce0
x5 : ffffb463aa47e378 x4 : 0000000000000000 x3 : 0000000000000cc0
x2 : 000000000000000d x1 : 000000000000000c x0 : 0000000000000000
Call trace:
 xas_split_alloc+0xf8/0x128
 split_huge_page_to_list_to_order+0x1c4/0x720
 truncate_inode_partial_folio+0xdc/0x160
 shmem_undo_range+0x2bc/0x6a8
 shmem_fallocate+0x134/0x430
 vfs_fallocate+0x124/0x2e8
 ksys_fallocate+0x4c/0xa0
 __arm64_sys_fallocate+0x24/0x38
 invoke_syscall.constprop.0+0x7c/0xd8
 do_el0_svc+0xb4/0xd0
 el0_svc+0x44/0x1d8
 el0t_64_sync_handler+0x134/0x150
 el0t_64_sync+0x17c/0x180


This patch (of 4):

The largest page cache order can be HPAGE_PMD_ORDER (13) on ARM64 with
64KB base page size.  The xarray entry with this order can't be split as
the following error messages indicate.

------------[ cut here ]------------
WARNING: CPU: 35 PID: 7484 at lib/xarray.c:1025 xas_split_alloc+0xf8/0x128
Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib  \
nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct    \
nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4    \
ip_set rfkill nf_tables nfnetlink vfat fat virtio_balloon drm      \
fuse xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64      \
sha1_ce virtio_net net_failover virtio_console virtio_blk failover \
dimlib virtio_mmio
CPU: 35 PID: 7484 Comm: test Kdump: loaded Tainted: G W 6.10.0-rc5-gavin+ #9
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-1.el9 05/24/2024
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : xas_split_alloc+0xf8/0x128
lr : split_huge_page_to_list_to_order+0x1c4/0x720
sp : ffff800087a4f6c0
x29: ffff800087a4f6c0 x28: ffff800087a4f720 x27: 000000001fffffff
x26: 0000000000000c40 x25: 000000000000000d x24: ffff00010625b858
x23: ffff800087a4f720 x22: ffffffdfc0780000 x21: 0000000000000000
x20: 0000000000000000 x19: ffffffdfc0780000 x18: 000000001ff40000
x17: 00000000ffffffff x16: 0000018000000000 x15: 51ec004000000000
x14: 0000e00000000000 x13: 0000000000002000 x12: 0000000000000020
x11: 51ec000000000000 x10: 51ece1c0ffff8000 x9 : ffffbeb961a44d28
x8 : 0000000000000003 x7 : ffffffdfc0456420 x6 : ffff0000e1aa6eb8
x5 : 20bf08b4fe778fca x4 : ffffffdfc0456420 x3 : 0000000000000c40
x2 : 000000000000000d x1 : 000000000000000c x0 : 0000000000000000
Call trace:
 xas_split_alloc+0xf8/0x128
 split_huge_page_to_list_to_order+0x1c4/0x720
 truncate_inode_partial_folio+0xdc/0x160
 truncate_inode_pages_range+0x1b4/0x4a8
 truncate_pagecache_range+0x84/0xa0
 xfs_flush_unmap_range+0x70/0x90 [xfs]
 xfs_file_fallocate+0xfc/0x4d8 [xfs]
 vfs_fallocate+0x124/0x2e8
 ksys_fallocate+0x4c/0xa0
 __arm64_sys_fallocate+0x24/0x38
 invoke_syscall.constprop.0+0x7c/0xd8
 do_el0_svc+0xb4/0xd0
 el0_svc+0x44/0x1d8
 el0t_64_sync_handler+0x134/0x150
 el0t_64_sync+0x17c/0x180

Fix it by decreasing MAX_PAGECACHE_ORDER to the largest supported order
by xarray. For this specific case, MAX_PAGECACHE_ORDER is dropped from
13 to 11 when CONFIG_BASE_SMALL is disabled.

Link: https://lkml.kernel.org/r/20240627003953.1262512-1-gshan@redhat.com
Link: https://lkml.kernel.org/r/20240627003953.1262512-2-gshan@redhat.com
Fixes: 793917d ("mm/readahead: Add large folio readahead")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Zhenyu Zhang <zhenyzha@redhat.com>
Cc: <stable@vger.kernel.org>	[5.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Jul 12, 2024
On ARM64, HPAGE_PMD_ORDER is 13 when the base page size is 64KB.  The
PMD-sized page cache can't be supported by xarray as the following error
messages indicate.

------------[ cut here ]------------
WARNING: CPU: 35 PID: 7484 at lib/xarray.c:1025 xas_split_alloc+0xf8/0x128
Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib  \
nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct    \
nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4    \
ip_set rfkill nf_tables nfnetlink vfat fat virtio_balloon drm      \
fuse xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64      \
sha1_ce virtio_net net_failover virtio_console virtio_blk failover \
dimlib virtio_mmio
CPU: 35 PID: 7484 Comm: test Kdump: loaded Tainted: G W 6.10.0-rc5-gavin+ #9
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-1.el9 05/24/2024
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : xas_split_alloc+0xf8/0x128
lr : split_huge_page_to_list_to_order+0x1c4/0x720
sp : ffff800087a4f6c0
x29: ffff800087a4f6c0 x28: ffff800087a4f720 x27: 000000001fffffff
x26: 0000000000000c40 x25: 000000000000000d x24: ffff00010625b858
x23: ffff800087a4f720 x22: ffffffdfc0780000 x21: 0000000000000000
x20: 0000000000000000 x19: ffffffdfc0780000 x18: 000000001ff40000
x17: 00000000ffffffff x16: 0000018000000000 x15: 51ec004000000000
x14: 0000e00000000000 x13: 0000000000002000 x12: 0000000000000020
x11: 51ec000000000000 x10: 51ece1c0ffff8000 x9 : ffffbeb961a44d28
x8 : 0000000000000003 x7 : ffffffdfc0456420 x6 : ffff0000e1aa6eb8
x5 : 20bf08b4fe778fca x4 : ffffffdfc0456420 x3 : 0000000000000c40
x2 : 000000000000000d x1 : 000000000000000c x0 : 0000000000000000
Call trace:
 xas_split_alloc+0xf8/0x128
 split_huge_page_to_list_to_order+0x1c4/0x720
 truncate_inode_partial_folio+0xdc/0x160
 truncate_inode_pages_range+0x1b4/0x4a8
 truncate_pagecache_range+0x84/0xa0
 xfs_flush_unmap_range+0x70/0x90 [xfs]
 xfs_file_fallocate+0xfc/0x4d8 [xfs]
 vfs_fallocate+0x124/0x2e8
 ksys_fallocate+0x4c/0xa0
 __arm64_sys_fallocate+0x24/0x38
 invoke_syscall.constprop.0+0x7c/0xd8
 do_el0_svc+0xb4/0xd0
 el0_svc+0x44/0x1d8
 el0t_64_sync_handler+0x134/0x150
 el0t_64_sync+0x17c/0x180

Fix it by skipping to allocate PMD-sized page cache when its size is
larger than MAX_PAGECACHE_ORDER.  For this specific case, we will fall to
regular path where the readahead window is determined by BDI's sysfs file
(read_ahead_kb).

Link: https://lkml.kernel.org/r/20240627003953.1262512-4-gshan@redhat.com
Fixes: 4687fdb ("mm/filemap: Support VM_HUGEPAGE for file mappings")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Zhenyu Zhang <zhenyzha@redhat.com>
Cc: <stable@vger.kernel.org>	[5.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Jul 12, 2024
For shmem files, it's possible that PMD-sized page cache can't be
supported by xarray.  For example, 512MB page cache on ARM64 when the base
page size is 64KB can't be supported by xarray.  It leads to errors as the
following messages indicate when this sort of xarray entry is split.

WARNING: CPU: 34 PID: 7578 at lib/xarray.c:1025 xas_split_alloc+0xf8/0x128
Modules linked in: binfmt_misc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6   \
nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject        \
nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4  \
ip_set rfkill nf_tables nfnetlink vfat fat virtio_balloon drm fuse xfs  \
libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce virtio_net \
net_failover virtio_console virtio_blk failover dimlib virtio_mmio
CPU: 34 PID: 7578 Comm: test Kdump: loaded Tainted: G W 6.10.0-rc5-gavin+ #9
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-1.el9 05/24/2024
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : xas_split_alloc+0xf8/0x128
lr : split_huge_page_to_list_to_order+0x1c4/0x720
sp : ffff8000882af5f0
x29: ffff8000882af5f0 x28: ffff8000882af650 x27: ffff8000882af768
x26: 0000000000000cc0 x25: 000000000000000d x24: ffff00010625b858
x23: ffff8000882af650 x22: ffffffdfc0900000 x21: 0000000000000000
x20: 0000000000000000 x19: ffffffdfc0900000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000018000000000 x15: 52f8004000000000
x14: 0000e00000000000 x13: 0000000000002000 x12: 0000000000000020
x11: 52f8000000000000 x10: 52f8e1c0ffff6000 x9 : ffffbeb9619a681c
x8 : 0000000000000003 x7 : 0000000000000000 x6 : ffff00010b02ddb0
x5 : ffffbeb96395e378 x4 : 0000000000000000 x3 : 0000000000000cc0
x2 : 000000000000000d x1 : 000000000000000c x0 : 0000000000000000
Call trace:
 xas_split_alloc+0xf8/0x128
 split_huge_page_to_list_to_order+0x1c4/0x720
 truncate_inode_partial_folio+0xdc/0x160
 shmem_undo_range+0x2bc/0x6a8
 shmem_fallocate+0x134/0x430
 vfs_fallocate+0x124/0x2e8
 ksys_fallocate+0x4c/0xa0
 __arm64_sys_fallocate+0x24/0x38
 invoke_syscall.constprop.0+0x7c/0xd8
 do_el0_svc+0xb4/0xd0
 el0_svc+0x44/0x1d8
 el0t_64_sync_handler+0x134/0x150
 el0t_64_sync+0x17c/0x180

Fix it by disabling PMD-sized page cache when HPAGE_PMD_ORDER is larger
than MAX_PAGECACHE_ORDER.  As Matthew Wilcox pointed, the page cache in a
shmem file isn't represented by a multi-index entry and doesn't have this
limitation when the xarry entry is split until commit 6b24ca4 ("mm:
Use multi-index entries in the page cache").

Link: https://lkml.kernel.org/r/20240627003953.1262512-5-gshan@redhat.com
Fixes: 6b24ca4 ("mm: Use multi-index entries in the page cache")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Zhenyu Zhang <zhenyzha@redhat.com>
Cc: <stable@vger.kernel.org>	[5.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Jul 22, 2024
If drivers don't do this then iommufd will oops invalidation ioctls with
something like:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
  Mem abort info:
    ESR = 0x0000000086000004
    EC = 0x21: IABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
    FSC = 0x04: level 0 translation fault
  user pgtable: 4k pages, 48-bit VAs, pgdp=0000000101059000
  [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
  Internal error: Oops: 0000000086000004 [#1] PREEMPT SMP
  Modules linked in:
  CPU: 2 PID: 371 Comm: qemu-system-aar Not tainted 6.8.0-rc7-gde77230ac23a #9
  Hardware name: linux,dummy-virt (DT)
  pstate: 81400809 (Nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=-c)
  pc : 0x0
  lr : iommufd_hwpt_invalidate+0xa4/0x204
  sp : ffff800080f3bcc0
  x29: ffff800080f3bcf0 x28: ffff0000c369b300 x27: 0000000000000000
  x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
  x23: 0000000000000000 x22: 00000000c1e334a0 x21: ffff0000c1e334a0
  x20: ffff800080f3bd38 x19: ffff800080f3bd58 x18: 0000000000000000
  x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffff8240d6d8
  x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
  x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
  x8 : 0000001000000002 x7 : 0000fffeac1ec950 x6 : 0000000000000000
  x5 : ffff800080f3bd78 x4 : 0000000000000003 x3 : 0000000000000002
  x2 : 0000000000000000 x1 : ffff800080f3bcc8 x0 : ffff0000c6034d80
  Call trace:
   0x0
   iommufd_fops_ioctl+0x154/0x274
   __arm64_sys_ioctl+0xac/0xf0
   invoke_syscall+0x48/0x110
   el0_svc_common.constprop.0+0x40/0xe0
   do_el0_svc+0x1c/0x28
   el0_svc+0x34/0xb4
   el0t_64_sync_handler+0x120/0x12c
   el0t_64_sync+0x190/0x194

All existing drivers implement this op for nesting, this is mostly a
bisection aid.

Fixes: 8c6eaba ("iommufd: Add IOMMU_HWPT_INVALIDATE")
Link: https://lore.kernel.org/r/0-v1-e153859bd707+61-iommufd_check_ops_jgg@nvidia.com
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
matttbe pushed a commit that referenced this issue Aug 2, 2024
xarray can't support arbitrary page cache size.  the largest and supported
page cache size is defined as MAX_PAGECACHE_ORDER by commit 099d906
("mm/filemap: make MAX_PAGECACHE_ORDER acceptable to xarray").  However,
it's possible to have 512MB page cache in the huge memory's collapsing
path on ARM64 system whose base page size is 64KB.  512MB page cache is
breaking the limitation and a warning is raised when the xarray entry is
split as shown in the following example.

[root@dhcp-10-26-1-207 ~]# cat /proc/1/smaps | grep KernelPageSize
KernelPageSize:       64 kB
[root@dhcp-10-26-1-207 ~]# cat /tmp/test.c
   :
int main(int argc, char **argv)
{
	const char *filename = TEST_XFS_FILENAME;
	int fd = 0;
	void *buf = (void *)-1, *p;
	int pgsize = getpagesize();
	int ret = 0;

	if (pgsize != 0x10000) {
		fprintf(stdout, "System with 64KB base page size is required!\n");
		return -EPERM;
	}

	system("echo 0 > /sys/devices/virtual/bdi/253:0/read_ahead_kb");
	system("echo 1 > /proc/sys/vm/drop_caches");

	/* Open the xfs file */
	fd = open(filename, O_RDONLY);
	assert(fd > 0);

	/* Create VMA */
	buf = mmap(NULL, TEST_MEM_SIZE, PROT_READ, MAP_SHARED, fd, 0);
	assert(buf != (void *)-1);
	fprintf(stdout, "mapped buffer at 0x%p\n", buf);

	/* Populate VMA */
	ret = madvise(buf, TEST_MEM_SIZE, MADV_NOHUGEPAGE);
	assert(ret == 0);
	ret = madvise(buf, TEST_MEM_SIZE, MADV_POPULATE_READ);
	assert(ret == 0);

	/* Collapse VMA */
	ret = madvise(buf, TEST_MEM_SIZE, MADV_HUGEPAGE);
	assert(ret == 0);
	ret = madvise(buf, TEST_MEM_SIZE, MADV_COLLAPSE);
	if (ret) {
		fprintf(stdout, "Error %d to madvise(MADV_COLLAPSE)\n", errno);
		goto out;
	}

	/* Split xarray entry. Write permission is needed */
	munmap(buf, TEST_MEM_SIZE);
	buf = (void *)-1;
	close(fd);
	fd = open(filename, O_RDWR);
	assert(fd > 0);
	fallocate(fd, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
 		  TEST_MEM_SIZE - pgsize, pgsize);
out:
	if (buf != (void *)-1)
		munmap(buf, TEST_MEM_SIZE);
	if (fd > 0)
		close(fd);

	return ret;
}

[root@dhcp-10-26-1-207 ~]# gcc /tmp/test.c -o /tmp/test
[root@dhcp-10-26-1-207 ~]# /tmp/test
 ------------[ cut here ]------------
 WARNING: CPU: 25 PID: 7560 at lib/xarray.c:1025 xas_split_alloc+0xf8/0x128
 Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib    \
 nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct      \
 nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4      \
 ip_set rfkill nf_tables nfnetlink vfat fat virtio_balloon drm fuse   \
 xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 virtio_net  \
 sha1_ce net_failover virtio_blk virtio_console failover dimlib virtio_mmio
 CPU: 25 PID: 7560 Comm: test Kdump: loaded Not tainted 6.10.0-rc7-gavin+ #9
 Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-1.el9 05/24/2024
 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
 pc : xas_split_alloc+0xf8/0x128
 lr : split_huge_page_to_list_to_order+0x1c4/0x780
 sp : ffff8000ac32f660
 x29: ffff8000ac32f660 x28: ffff0000e0969eb0 x27: ffff8000ac32f6c0
 x26: 0000000000000c40 x25: ffff0000e0969eb0 x24: 000000000000000d
 x23: ffff8000ac32f6c0 x22: ffffffdfc0700000 x21: 0000000000000000
 x20: 0000000000000000 x19: ffffffdfc0700000 x18: 0000000000000000
 x17: 0000000000000000 x16: ffffd5f3708ffc70 x15: 0000000000000000
 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
 x11: ffffffffffffffc0 x10: 0000000000000040 x9 : ffffd5f3708e692c
 x8 : 0000000000000003 x7 : 0000000000000000 x6 : ffff0000e0969eb8
 x5 : ffffd5f37289e378 x4 : 0000000000000000 x3 : 0000000000000c40
 x2 : 000000000000000d x1 : 000000000000000c x0 : 0000000000000000
 Call trace:
  xas_split_alloc+0xf8/0x128
  split_huge_page_to_list_to_order+0x1c4/0x780
  truncate_inode_partial_folio+0xdc/0x160
  truncate_inode_pages_range+0x1b4/0x4a8
  truncate_pagecache_range+0x84/0xa0
  xfs_flush_unmap_range+0x70/0x90 [xfs]
  xfs_file_fallocate+0xfc/0x4d8 [xfs]
  vfs_fallocate+0x124/0x2f0
  ksys_fallocate+0x4c/0xa0
  __arm64_sys_fallocate+0x24/0x38
  invoke_syscall.constprop.0+0x7c/0xd8
  do_el0_svc+0xb4/0xd0
  el0_svc+0x44/0x1d8
  el0t_64_sync_handler+0x134/0x150
  el0t_64_sync+0x17c/0x180

Fix it by correcting the supported page cache orders, different sets for
DAX and other files.  With it corrected, 512MB page cache becomes
disallowed on all non-DAX files on ARM64 system where the base page size
is 64KB.  After this patch is applied, the test program fails with error
-EINVAL returned from __thp_vma_allowable_orders() and the madvise()
system call to collapse the page caches.

Link: https://lkml.kernel.org/r/20240715000423.316491-1-gshan@redhat.com
Fixes: 6b24ca4 ("mm: Use multi-index entries in the page cache")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: <stable@vger.kernel.org>	[5.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
matttbe pushed a commit that referenced this issue Aug 9, 2024
When l2tp tunnels use a socket provided by userspace, we can hit
lockdep splats like the below when data is transmitted through another
(unrelated) userspace socket which then gets routed over l2tp.

This issue was previously discussed here:
https://lore.kernel.org/netdev/87sfialu2n.fsf@cloudflare.com/

The solution is to have lockdep treat socket locks of l2tp tunnel
sockets separately than those of standard INET sockets. To do so, use
a different lockdep subclass where lock nesting is possible.

  ============================================
  WARNING: possible recursive locking detected
  6.10.0+ #34 Not tainted
  --------------------------------------------
  iperf3/771 is trying to acquire lock:
  ffff8881027601d8 (slock-AF_INET/1){+.-.}-{2:2}, at: l2tp_xmit_skb+0x243/0x9d0

  but task is already holding lock:
  ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(slock-AF_INET/1);
    lock(slock-AF_INET/1);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  10 locks held by iperf3/771:
   #0: ffff888102650258 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x1a/0x40
   #1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0
   #4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260
   #5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10
   #6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450
   #9: ffff888101f33258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x513/0x1450

  stack backtrace:
  CPU: 2 UID: 0 PID: 771 Comm: iperf3 Not tainted 6.10.0+ #34
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x69/0xa0
   dump_stack+0xc/0x20
   __lock_acquire+0x135d/0x2600
   ? srso_alias_return_thunk+0x5/0xfbef5
   lock_acquire+0xc4/0x2a0
   ? l2tp_xmit_skb+0x243/0x9d0
   ? __skb_checksum+0xa3/0x540
   _raw_spin_lock_nested+0x35/0x50
   ? l2tp_xmit_skb+0x243/0x9d0
   l2tp_xmit_skb+0x243/0x9d0
   l2tp_eth_dev_xmit+0x3c/0xc0
   dev_hard_start_xmit+0x11e/0x420
   sch_direct_xmit+0xc3/0x640
   __dev_queue_xmit+0x61c/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   __tcp_send_ack+0x1b8/0x340
   tcp_send_ack+0x23/0x30
   __tcp_ack_snd_check+0xa8/0x530
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_rcv_established+0x412/0xd70
   tcp_v4_do_rcv+0x299/0x420
   tcp_v4_rcv+0x1991/0x1e10
   ip_protocol_deliver_rcu+0x50/0x220
   ip_local_deliver_finish+0x158/0x260
   ip_local_deliver+0xc8/0xe0
   ip_rcv+0xe5/0x1d0
   ? __pfx_ip_rcv+0x10/0x10
   __netif_receive_skb_one_core+0xce/0xe0
   ? process_backlog+0x28b/0x9f0
   __netif_receive_skb+0x34/0xd0
   ? process_backlog+0x28b/0x9f0
   process_backlog+0x2cb/0x9f0
   __napi_poll.constprop.0+0x61/0x280
   net_rx_action+0x332/0x670
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? find_held_lock+0x2b/0x80
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   handle_softirqs+0xda/0x480
   ? __dev_queue_xmit+0xa2c/0x1450
   do_softirq+0xa1/0xd0
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0xc8/0xe0
   ? __dev_queue_xmit+0xa2c/0x1450
   __dev_queue_xmit+0xa48/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   tcp_write_xmit+0x766/0x2fb0
   ? __entry_text_end+0x102ba9/0x102bad
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_fault+0x74/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   __tcp_push_pending_frames+0x56/0x190
   tcp_push+0x117/0x310
   tcp_sendmsg_locked+0x14c1/0x1740
   tcp_sendmsg+0x28/0x40
   inet_sendmsg+0x5d/0x90
   sock_write_iter+0x242/0x2b0
   vfs_write+0x68d/0x800
   ? __pfx_sock_write_iter+0x10/0x10
   ksys_write+0xc8/0xf0
   __x64_sys_write+0x3d/0x50
   x64_sys_call+0xfaf/0x1f50
   do_syscall_64+0x6d/0x140
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f4d143af992
  Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> e9 01 cc ff ff 41 54 b8 02 00 00 0
  RSP: 002b:00007ffd65032058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f4d143af992
  RDX: 0000000000000025 RSI: 00007f4d143f3bcc RDI: 0000000000000005
  RBP: 00007f4d143f2b28 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d143f3bcc
  R13: 0000000000000005 R14: 0000000000000000 R15: 00007ffd650323f0
   </TASK>

Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()")
Suggested-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+6acef9e0a4d1f46c83d4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4
CC: gnault@redhat.com
CC: cong.wang@bytedance.com
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Link: https://patch.msgid.link/20240806160626.1248317-1-jchapman@katalix.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Aug 12, 2024
Tariq Toukan says:

====================
mlx5 misc patches 2024-08-08

This patchset contains multiple enhancements from the team to the mlx5
core and Eth drivers.

Patch #1 by Chris bumps a defined value to permit more devices doing TC
offloads.

Patch #2 by Jianbo adds an IPsec fast-path optimization to replace the
slow async handling.

Patches #3 and #4 by Jianbo add TC offload support for complicated rules
to overcome firmware limitation.

Patch #5 by Gal unifies the access macro to advertised/supported link
modes.

Patches #6 to #9 by Gal adds extack messages in ethtool ops to replace
prints to the kernel log.

Patch #10 by Cosmin switches to using 'update' verb instead of 'replace'
to better reflect the operation.

Patch #11 by Cosmin exposes an update connection tracking operation to
replace the assumed delete+add implementaiton.
====================

Link: https://patch.msgid.link/20240808055927.2059700-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Aug 27, 2024
…rnel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following batch contains Netfilter updates for net-next:

Patch #1 fix checksum calculation in nfnetlink_queue with SCTP,
	 segment GSO packet since skb_zerocopy() does not support
	 GSO_BY_FRAGS, from Antonio Ojea.

Patch #2 extend nfnetlink_queue coverage to handle SCTP packets,
	 from Antonio Ojea.

Patch #3 uses consume_skb() instead of kfree_skb() in nfnetlink,
         from Donald Hunter.

Patch #4 adds a dedicate commit list for sets to speed up
	 intra-transaction lookups, from Florian Westphal.

Patch #5 skips removal of element from abort path for the pipapo
         backend, ditching the shadow copy of this datastructure
	 is sufficient.

Patch #6 moves nf_ct_netns_get() out of nf_conncount_init() to
	 let users of conncoiunt decide when to enable conntrack,
	 this is needed by openvswitch, from Xin Long.

Patch #7 pass context to all nft_parse_register_load() in
	 preparation for the next patch.

Patches #8 and #9 reject loads from uninitialized registers from
	 control plane to remove register initialization from
	 datapath. From Florian Westphal.

* tag 'nf-next-24-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: don't initialize registers in nft_do_chain()
  netfilter: nf_tables: allow loads only when register is initialized
  netfilter: nf_tables: pass context structure to nft_parse_register_load
  netfilter: move nf_ct_netns_get out of nf_conncount_init
  netfilter: nf_tables: do not remove elements if set backend implements .abort
  netfilter: nf_tables: store new sets in dedicated list
  netfilter: nfnetlink: convert kfree_skb to consume_skb
  selftests: netfilter: nft_queue.sh: sctp coverage
  netfilter: nfnetlink_queue: unbreak SCTP traffic
====================

Link: https://patch.msgid.link/20240822221939.157858-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Aug 27, 2024
A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 4, 2024
Daniel Machon says:

====================
net: microchip: add FDMA library and use it for Sparx5

This patch series is the first of a 2-part series, that adds a new
common FDMA library for Microchip switch chips Sparx5 and lan966x. These
chips share the same FDMA engine, and as such will benefit from a
common library with a common implementation.  This also has the benefit
of removing a lot open-coded bookkeeping and duplicate code for the two
drivers.

Additionally, upstreaming efforts for a third chip, lan969x, will begin
in the near future. This chip will use the new library too.

In this first series, the FDMA library is introduced and used by the
Sparx5 switch driver.

 ###################
 # Example of use: #
 ###################

- Initialize the rx and tx fdma structs with values for: number of
  DCB's, number of DB's, channel ID, DB size (data buffer size), and
  total size of the requested memory. Also provide two callbacks:
  nextptr_cb() and dataptr_cb() for getting the nextptr and dataptr.

- Allocate memory using fdma_alloc_phys() or fdma_alloc_coherent().

- Initialize the DCB's with fdma_dcb_init().

- Add new DCB's with fdma_dcb_add().

- Free memory with fdma_free_phys() or fdma_free_coherent().

 #####################
 # Patch  breakdown: #
 #####################

Patch #1:  introduces library and selects it for Sparx5.

Patch #2:  includes the fdma_api.h header and removes old symbols.

Patch #3:  replaces old rx and tx variables with equivalent ones from the
           fdma struct. Only the variables that can be changed without
           breaking traffic is changed in this patch.

Patch #4:  uses the library for allocation of rx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #5:  uses the library for adding DCB's in the rx path.

Patch #6:  uses the library for freeing rx buffers.

Patch #7:  uses the library helpers in the rx path.

Patch #8:  uses the library for allocation of tx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #9:  uses the library for adding DCB's in the tx path.

Patch #10: uses the library helpers in the tx path.

Patch #11: ditches the existing linked list for storing buffer addresses,
           and instead uses offsets into contiguous memory.

Patch #12: modifies existing rx and tx functions to be direction
           independent.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
matttbe pushed a commit that referenced this issue Sep 9, 2024
…rnel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

Patch #1 adds ctnetlink support for kernel side filtering for
	 deletions, from Changliang Wu.

Patch #2 updates nft_counter support to Use u64_stats_t,
	 from Sebastian Andrzej Siewior.

Patch #3 uses kmemdup_array() in all xtables frontends,
	 from Yan Zhen.

Patch #4 is a oneliner to use ERR_CAST() in nf_conntrack instead
	 opencoded casting, from Shen Lichuan.

Patch #5 removes unused argument in nftables .validate interface,
	 from Florian Westphal.

Patch #6 is a oneliner to correct a typo in nftables kdoc,
	 from Simon Horman.

Patch #7 fixes missing kdoc in nftables, also from Simon.

Patch #8 updates nftables to handle timeout less than CONFIG_HZ.

Patch #9 rejects element expiration if timeout is zero,
	 otherwise it is silently ignored.

Patch #10 disallows element expiration larger than timeout.

Patch #11 removes unnecessary READ_ONCE annotation while mutex is held.

Patch #12 adds missing READ_ONCE/WRITE_ONCE annotation in dynset.

Patch #13 annotates data-races around element expiration.

Patch #14 allocates timeout and expiration in one single set element
	  extension, they are tighly couple, no reason to keep them
	  separated anymore.

Patch #15 updates nftables to interpret zero timeout element as never
	  times out. Note that it is already possible to declare sets
	  with elements that never time out but this generalizes to all
	  kind of set with timeouts.

Patch #16 supports for element timeout and expiration updates.

* tag 'nf-next-24-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: set element timeout update support
  netfilter: nf_tables: zero timeout means element never times out
  netfilter: nf_tables: consolidate timeout extension for elements
  netfilter: nf_tables: annotate data-races around element expiration
  netfilter: nft_dynset: annotate data-races around set timeout
  netfilter: nf_tables: remove annotation to access set timeout while holding lock
  netfilter: nf_tables: reject expiration higher than timeout
  netfilter: nf_tables: reject element expiration with no timeout
  netfilter: nf_tables: elements with timeout below CONFIG_HZ never expire
  netfilter: nf_tables: Add missing Kernel doc
  netfilter: nf_tables: Correct spelling in nf_tables.h
  netfilter: nf_tables: drop unused 3rd argument from validate callback ops
  netfilter: conntrack: Convert to use ERR_CAST()
  netfilter: Use kmemdup_array instead of kmemdup for multiple allocation
  netfilter: nft_counter: Use u64_stats_t for statistic.
  netfilter: ctnetlink: support CTA_FILTER for flush
====================

Link: https://patch.msgid.link/20240905232920.5481-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Sep 11, 2024
Daniel Machon says:

====================
net: lan966x: use the newly introduced FDMA library

This patch series is the second of a 2-part series [1], that adds a new
common FDMA library for Microchip switch chips Sparx5 and lan966x. These
chips share the same FDMA engine, and as such will benefit from a common
library with a common implementation.  This also has the benefit of
removing a lot of open-coded bookkeeping and duplicate code for the two
drivers.

In this second series, the FDMA library will be taken into use by the
lan966x switch driver.

 ###################
 # Example of use: #
 ###################

- Initialize the rx and tx fdma structs with values for: number of
  DCB's, number of DB's, channel ID, DB size (data buffer size), and
  total size of the requested memory. Also provide two callbacks:
  nextptr_cb() and dataptr_cb() for getting the nextptr and dataptr.

- Allocate memory using fdma_alloc_phys() or fdma_alloc_coherent().

- Initialize the DCB's with fdma_dcb_init().

- Add new DCB's with fdma_dcb_add().

- Free memory with fdma_free_phys() or fdma_free_coherent().

 #####################
 # Patch  breakdown: #
 #####################

Patch #1:  select FDMA library for lan966x.

Patch #2:  includes the fdma_api.h header and removes old symbols.

Patch #3:  replaces old rx and tx variables with equivalent ones from the
           fdma struct. Only the variables that can be changed without
           breaking traffic is changed in this patch.

Patch #4:  uses the library for allocation of rx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #5:  uses the library for adding DCB's in the rx path.

Patch #6:  uses the library for freeing rx buffers.

Patch #7:  uses the library for allocation of tx buffers. This requires
           quite a bit of refactoring in this single patch.

Patch #8:  uses the library for adding DCB's in the tx path.

Patch #9:  uses the library helpers in the tx path.

Patch #10: ditch last_in_use variable and use library instead.

Patch #11: uses library helpers throughout.

Patch #12: refactor lan966x_fdma_reload() function.

[1] https://lore.kernel.org/netdev/20240902-fdma-sparx5-v1-0-1e7d5e5a9f34@microchip.com/

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
====================

Link: https://patch.msgid.link/20240905-fdma-lan966x-v1-0-e083f8620165@microchip.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
matttbe pushed a commit that referenced this issue Oct 18, 2024
On the node of an NFS client, some files saved in the mountpoint of the
NFS server were copied to another location of the same NFS server.
Accidentally, the nfs42_complete_copies() got a NULL-pointer dereference
crash with the following syslog:

[232064.838881] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232064.839360] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232066.588183] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
[232066.588586] Mem abort info:
[232066.588701]   ESR = 0x0000000096000007
[232066.588862]   EC = 0x25: DABT (current EL), IL = 32 bits
[232066.589084]   SET = 0, FnV = 0
[232066.589216]   EA = 0, S1PTW = 0
[232066.589340]   FSC = 0x07: level 3 translation fault
[232066.589559] Data abort info:
[232066.589683]   ISV = 0, ISS = 0x00000007
[232066.589842]   CM = 0, WnR = 0
[232066.589967] user pgtable: 64k pages, 48-bit VAs, pgdp=00002000956ff400
[232066.590231] [0000000000000058] pgd=08001100ae100003, p4d=08001100ae100003, pud=08001100ae100003, pmd=08001100b3c00003, pte=0000000000000000
[232066.590757] Internal error: Oops: 96000007 [#1] SMP
[232066.590958] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm vhost_net vhost vhost_iotlb tap tun ipt_rpfilter xt_multiport ip_set_hash_ip ip_set_hash_net xfrm_interface xfrm6_tunnel tunnel4 tunnel6 esp4 ah4 wireguard libcurve25519_generic veth xt_addrtype xt_set nf_conntrack_netlink ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_bitmap_port ip_set_hash_ipport dummy ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs iptable_filter sch_ingress nfnetlink_cttimeout vport_gre ip_gre ip_tunnel gre vport_geneve geneve vport_vxlan vxlan ip6_udp_tunnel udp_tunnel openvswitch nf_conncount dm_round_robin dm_service_time dm_multipath xt_nat xt_MASQUERADE nft_chain_nat nf_nat xt_mark xt_conntrack xt_comment nft_compat nft_counter nf_tables nfnetlink ocfs2 ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif nbd overlay 8021q garp mrp bonding tls rfkill sunrpc ext4 mbcache jbd2
[232066.591052]  vfat fat cas_cache cas_disk ses enclosure scsi_transport_sas sg acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler ip_tables vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio dm_mirror dm_region_hash dm_log dm_mod nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter bridge stp llc fuse xfs libcrc32c ast drm_vram_helper qla2xxx drm_kms_helper syscopyarea crct10dif_ce sysfillrect ghash_ce sysimgblt sha2_ce fb_sys_fops cec sha256_arm64 sha1_ce drm_ttm_helper ttm nvme_fc igb sbsa_gwdt nvme_fabrics drm nvme_core i2c_algo_bit i40e scsi_transport_fc megaraid_sas aes_neon_bs
[232066.596953] CPU: 6 PID: 4124696 Comm: 10.253.166.125- Kdump: loaded Not tainted 5.15.131-9.cl9_ocfs2.aarch64 #1
[232066.597356] Hardware name: Great Wall .\x93\x8e...RF6260 V5/GWMSSE2GL1T, BIOS T656FBE_V3.0.18 2024-01-06
[232066.597721] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[232066.598034] pc : nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.598327] lr : nfs4_reclaim_open_state+0x12c/0x800 [nfsv4]
[232066.598595] sp : ffff8000f568fc70
[232066.598731] x29: ffff8000f568fc70 x28: 0000000000001000 x27: ffff21003db33000
[232066.599030] x26: ffff800005521ae0 x25: ffff0100f98fa3f0 x24: 0000000000000001
[232066.599319] x23: ffff800009920008 x22: ffff21003db33040 x21: ffff21003db33050
[232066.599628] x20: ffff410172fe9e40 x19: ffff410172fe9e00 x18: 0000000000000000
[232066.599914] x17: 0000000000000000 x16: 0000000000000004 x15: 0000000000000000
[232066.600195] x14: 0000000000000000 x13: ffff800008e685a8 x12: 00000000eac0c6e6
[232066.600498] x11: 0000000000000000 x10: 0000000000000008 x9 : ffff8000054e5828
[232066.600784] x8 : 00000000ffffffbf x7 : 0000000000000001 x6 : 000000000a9eb14a
[232066.601062] x5 : 0000000000000000 x4 : ffff70ff8a14a800 x3 : 0000000000000058
[232066.601348] x2 : 0000000000000001 x1 : 54dce46366daa6c6 x0 : 0000000000000000
[232066.601636] Call trace:
[232066.601749]  nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.601998]  nfs4_do_reclaim+0x1b8/0x28c [nfsv4]
[232066.602218]  nfs4_state_manager+0x928/0x10f0 [nfsv4]
[232066.602455]  nfs4_run_state_manager+0x78/0x1b0 [nfsv4]
[232066.602690]  kthread+0x110/0x114
[232066.602830]  ret_from_fork+0x10/0x20
[232066.602985] Code: 1400000d f9403f20 f9402e61 91016003 (f9402c00)
[232066.603284] SMP: stopping secondary CPUs
[232066.606936] Starting crashdump kernel...
[232066.607146] Bye!

Analysing the vmcore, we know that nfs4_copy_state listed by destination
nfs_server->ss_copies was added by the field copies in handle_async_copy(),
and we found a waiting copy process with the stack as:
PID: 3511963  TASK: ffff710028b47e00  CPU: 0   COMMAND: "cp"
 #0 [ffff8001116ef740] __switch_to at ffff8000081b92f4
 #1 [ffff8001116ef760] __schedule at ffff800008dd0650
 #2 [ffff8001116ef7c0] schedule at ffff800008dd0a00
 #3 [ffff8001116ef7e0] schedule_timeout at ffff800008dd6aa0
 #4 [ffff8001116ef860] __wait_for_common at ffff800008dd166c
 #5 [ffff8001116ef8e0] wait_for_completion_interruptible at ffff800008dd1898
 #6 [ffff8001116ef8f0] handle_async_copy at ffff8000055142f4 [nfsv4]
 #7 [ffff8001116ef970] _nfs42_proc_copy at ffff8000055147c8 [nfsv4]
 #8 [ffff8001116efa80] nfs42_proc_copy at ffff800005514cf0 [nfsv4]
 #9 [ffff8001116efc50] __nfs4_copy_file_range.constprop.0 at ffff8000054ed694 [nfsv4]

The NULL-pointer dereference was due to nfs42_complete_copies() listed
the nfs_server->ss_copies by the field ss_copies of nfs4_copy_state.
So the nfs4_copy_state address ffff0100f98fa3f0 was offset by 0x10 and
the data accessed through this pointer was also incorrect. Generally,
the ordered list nfs4_state_owner->so_states indicate open(O_RDWR) or
open(O_WRITE) states are reclaimed firstly by nfs4_reclaim_open_state().
When destination state reclaim is failed with NFS_STATE_RECOVERY_FAILED
and copies are not deleted in nfs_server->ss_copies, the source state
may be passed to the nfs42_complete_copies() process earlier, resulting
in this crash scene finally. To solve this issue, we add a list_head
nfs_server->ss_src_copies for a server-to-server copy specially.

Fixes: 0e65a32 ("NFS: handle source server reboot")
Signed-off-by: Yanjun Zhang <zhangyanjun@cestc.cn>
Reviewed-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
matttbe pushed a commit that referenced this issue Oct 31, 2024
Daniel Machon says:

====================
net: sparx5: add support for lan969x switch device

== Description:

This series is the second of a multi-part series, that prepares and adds
support for the new lan969x switch driver.

The upstreaming efforts is split into multiple series (might change a
bit as we go along):

        1) Prepare the Sparx5 driver for lan969x (merged)

    --> 2) add support lan969x (same basic features as Sparx5
           provides excl. FDMA and VCAP).

        3) Add support for lan969x VCAP, FDMA and RGMII

== Lan969x in short:

The lan969x Ethernet switch family [1] provides a rich set of
switching features and port configurations (up to 30 ports) from 10Mbps
to 10Gbps, with support for RGMII, SGMII, QSGMII, USGMII, and USXGMII,
ideal for industrial & process automation infrastructure applications,
transport, grid automation, power substation automation, and ring &
intra-ring topologies. The LAN969x family is hardware and software
compatible and scalable supporting 46Gbps to 102Gbps switch bandwidths.

== Preparing Sparx5 for lan969x:

The main preparation work for lan969x has already been merged [1].

After this series is applied, lan969x will have the same functionality
as Sparx5, except for VCAP and FDMA support. QoS features that requires
the VCAP (e.g. PSFP, port mirroring) will obviously not work until VCAP
support is added later.

== Patch breakdown:

Patch #1-#4  do some preparation work for lan969x

Patch #5     adds new registers required by lan969x

Patch #6     adds initial match data for all lan969x targets

Patch #7     defines the lan969x register differences

Patch #8     adds lan969x constants to match data

Patch #9     adds some lan969x ops in bulk

Patch #10    adds PTP function to ops

Patch #11    adds lan969x_calendar.c for calculating the calendar

Patch #12    makes additional use of the is_sparx5() macro to branch out
             in certain places.

Patch #13    documents lan969x in the dt-bindings

Patch #14    adds lan969x compatible string to sparx5 driver

Patch #15    introduces new concept of per-target features

[1] https://lore.kernel.org/netdev/20241004-b4-sparx5-lan969x-switch-driver-v2-0-d3290f581663@microchip.com/

v1: https://lore.kernel.org/20241021-sparx5-lan969x-switch-driver-2-v1-0-c8c49ef21e0f@microchip.com
====================

Link: https://patch.msgid.link/20241024-sparx5-lan969x-switch-driver-2-v2-0-a0b5fae88a0f@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Nov 1, 2024
There is a race between laundromat handling of revoked delegations
and a client sending free_stateid operation. Laundromat thread
finds that delegation has expired and needs to be revoked so it
marks the delegation stid revoked and it puts it on a reaper list
but then it unlock the state lock and the actual delegation revocation
happens without the lock. Once the stid is marked revoked a racing
free_stateid processing thread does the following (1) it calls
list_del_init() which removes it from the reaper list and (2) frees
the delegation stid structure. The laundromat thread ends up not
calling the revoke_delegation() function for this particular delegation
but that means it will no release the lock lease that exists on
the file.

Now, a new open for this file comes in and ends up finding that
lease list isn't empty and calls nfsd_breaker_owns_lease() which ends
up trying to derefence a freed delegation stateid. Leading to the
followint use-after-free KASAN warning:

kernel: ==================================================================
kernel: BUG: KASAN: slab-use-after-free in nfsd_breaker_owns_lease+0x140/0x160 [nfsd]
kernel: Read of size 8 at addr ffff0000e73cd0c8 by task nfsd/6205
kernel:
kernel: CPU: 2 UID: 0 PID: 6205 Comm: nfsd Kdump: loaded Not tainted 6.11.0-rc7+ #9
kernel: Hardware name: Apple Inc. Apple Virtualization Generic Platform, BIOS 2069.0.0.0.0 08/03/2024
kernel: Call trace:
kernel: dump_backtrace+0x98/0x120
kernel: show_stack+0x1c/0x30
kernel: dump_stack_lvl+0x80/0xe8
kernel: print_address_description.constprop.0+0x84/0x390
kernel: print_report+0xa4/0x268
kernel: kasan_report+0xb4/0xf8
kernel: __asan_report_load8_noabort+0x1c/0x28
kernel: nfsd_breaker_owns_lease+0x140/0x160 [nfsd]
kernel: nfsd_file_do_acquire+0xb3c/0x11d0 [nfsd]
kernel: nfsd_file_acquire_opened+0x84/0x110 [nfsd]
kernel: nfs4_get_vfs_file+0x634/0x958 [nfsd]
kernel: nfsd4_process_open2+0xa40/0x1a40 [nfsd]
kernel: nfsd4_open+0xa08/0xe80 [nfsd]
kernel: nfsd4_proc_compound+0xb8c/0x2130 [nfsd]
kernel: nfsd_dispatch+0x22c/0x718 [nfsd]
kernel: svc_process_common+0x8e8/0x1960 [sunrpc]
kernel: svc_process+0x3d4/0x7e0 [sunrpc]
kernel: svc_handle_xprt+0x828/0xe10 [sunrpc]
kernel: svc_recv+0x2cc/0x6a8 [sunrpc]
kernel: nfsd+0x270/0x400 [nfsd]
kernel: kthread+0x288/0x310
kernel: ret_from_fork+0x10/0x20

This patch proposes a fixed that's based on adding 2 new additional
stid's sc_status values that help coordinate between the laundromat
and other operations (nfsd4_free_stateid() and nfsd4_delegreturn()).

First to make sure, that once the stid is marked revoked, it is not
removed by the nfsd4_free_stateid(), the laundromat take a reference
on the stateid. Then, coordinating whether the stid has been put
on the cl_revoked list or we are processing FREE_STATEID and need to
make sure to remove it from the list, each check that state and act
accordingly. If laundromat has added to the cl_revoke list before
the arrival of FREE_STATEID, then nfsd4_free_stateid() knows to remove
it from the list. If nfsd4_free_stateid() finds that operations arrived
before laundromat has placed it on cl_revoke list, it marks the state
freed and then laundromat will no longer add it to the list.

Also, for nfsd4_delegreturn() when looking for the specified stid,
we need to access stid that are marked removed or freeable, it means
the laundromat has started processing it but hasn't finished and this
delegreturn needs to return nfserr_deleg_revoked and not
nfserr_bad_stateid. The latter will not trigger a FREE_STATEID and the
lack of it will leave this stid on the cl_revoked list indefinitely.

Fixes: 2d4a532 ("nfsd: ensure that clp->cl_revoked list is protected by clp->cl_lock")
CC: stable@vger.kernel.org
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
matttbe pushed a commit that referenced this issue Dec 10, 2024
Petr Machata says:

====================
vxlan: Support user-defined reserved bits

Currently the VXLAN header validation works by vxlan_rcv() going feature
by feature, each feature clearing the bits that it consumes. If anything
is left unparsed at the end, the packet is rejected.

Unfortunately there are machines out there that send VXLAN packets with
reserved bits set, even if they are configured to not use the
corresponding features. One such report is here[1], and we have heard
similar complaints from our customers as well.

This patchset adds an attribute that makes it configurable which bits
the user wishes to tolerate and which they consider reserved. This was
recommended in [1] as well.

A knob like that inevitably allows users to set as reserved bits that
are in fact required for the features enabled by the netdevice, such as
GPE. This is detected, and such configurations are rejected.

In patches #1..#7, the reserved bits validation code is gradually moved
away from the unparsed approach described above, to one where a given
set of valid bits is precomputed and then the packet is validated
against that.

In patch #8, this precomputed set is made configurable through a new
attribute IFLA_VXLAN_RESERVED_BITS.

Patches #9 and #10 massage the testsuite a bit, so that patch #11 can
introduce a selftest for the resreved bits feature.

The corresponding iproute2 support is available in [2].

[1] https://lore.kernel.org/netdev/db8b9e19-ad75-44d3-bfb2-46590d426ff5@proxmox.com/
[2] https://github.com/pmachata/iproute2/commits/vxlan_reserved_bits/
====================

Link: https://patch.msgid.link/cover.1733412063.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
matttbe pushed a commit that referenced this issue Dec 13, 2024
Kernel will hang on destroy admin_q while we create ctrl failed, such
as following calltrace:

PID: 23644    TASK: ff2d52b40f439fc0  CPU: 2    COMMAND: "nvme"
 #0 [ff61d23de260fb78] __schedule at ffffffff8323bc15
 #1 [ff61d23de260fc08] schedule at ffffffff8323c014
 #2 [ff61d23de260fc28] blk_mq_freeze_queue_wait at ffffffff82a3dba1
 #3 [ff61d23de260fc78] blk_freeze_queue at ffffffff82a4113a
 #4 [ff61d23de260fc90] blk_cleanup_queue at ffffffff82a33006
 #5 [ff61d23de260fcb0] nvme_rdma_destroy_admin_queue at ffffffffc12686ce
 #6 [ff61d23de260fcc8] nvme_rdma_setup_ctrl at ffffffffc1268ced
 #7 [ff61d23de260fd28] nvme_rdma_create_ctrl at ffffffffc126919b
 #8 [ff61d23de260fd68] nvmf_dev_write at ffffffffc024f362
 #9 [ff61d23de260fe38] vfs_write at ffffffff827d5f25
    RIP: 00007fda7891d574  RSP: 00007ffe2ef06958  RFLAGS: 00000202
    RAX: ffffffffffffffda  RBX: 000055e8122a4d90  RCX: 00007fda7891d574
    RDX: 000000000000012b  RSI: 000055e8122a4d90  RDI: 0000000000000004
    RBP: 00007ffe2ef079c0   R8: 000000000000012b   R9: 000055e8122a4d90
    R10: 0000000000000000  R11: 0000000000000202  R12: 0000000000000004
    R13: 000055e8122923c0  R14: 000000000000012b  R15: 00007fda78a54500
    ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

This due to we have quiesced admi_q before cancel requests, but forgot
to unquiesce before destroy it, as a result we fail to drain the
pending requests, and hang on blk_mq_freeze_queue_wait() forever. Here
try to reuse nvme_rdma_teardown_admin_queue() to fix this issue and
simplify the code.

Fixes: 958dc1d ("nvme-rdma: add clean action for failed reconnection")
Reported-by: Yingfu.zhou <yingfu.zhou@shopee.com>
Signed-off-by: Chunguang.xu <chunguang.xu@shopee.com>
Signed-off-by: Yue.zhao <yue.zhao@shopee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
matttbe pushed a commit that referenced this issue Dec 13, 2024
Hou Tao says:

====================
This patch set fixes several issues for LPM trie. These issues were
found during adding new test cases or were reported by syzbot.

The patch set is structured as follows:

Patch #1~#2 are clean-ups for lpm_trie_update_elem().
Patch #3 handles BPF_EXIST and BPF_NOEXIST correctly for LPM trie.
Patch #4 fixes the accounting of n_entries when doing in-place update.
Patch #5 fixes the exact match condition in trie_get_next_key() and it
may skip keys when the passed key is not found in the map.
Patch #6~#7 switch from kmalloc() to bpf memory allocator for LPM trie
to fix several lock order warnings reported by syzbot. It also enables
raw_spinlock_t for LPM trie again. After these changes, the LPM trie will
be closer to being usable in any context (though the reentrance check of
trie->lock is still missing, but it is on my todo list).
Patch #8: move test_lpm_map to map_tests to make it run regularly.
Patch #9: add test cases for the issues fixed by patch #3~#5.

Please see individual patches for more details. Comments are always
welcome.

Change Log:
v3:
  * patch #2: remove the unnecessary NULL-init for im_node
  * patch #6: alloc the leaf node before disabling IRQ to low
    the possibility of -ENOMEM when leaf_size is large; Free
    these nodes outside the trie lock (Suggested by Alexei)
  * collect review and ack tags (Thanks for Toke & Daniel)

v2: https://lore.kernel.org/bpf/20241127004641.1118269-1-houtao@huaweicloud.com/
  * collect review tags (Thanks for Toke)
  * drop "Add bpf_mem_cache_is_mergeable() helper" patch
  * patch #3~#4: add fix tag
  * patch #4: rename the helper to trie_check_add_elem() and increase
    n_entries in it.
  * patch #6: use one bpf mem allocator and update commit message to
    clarify that using bpf mem allocator is more appropriate.
  * patch #7: update commit message to add the possible max running time
    for update operation.
  * patch #9: update commit message to specify the purpose of these test
    cases.

v1: https://lore.kernel.org/bpf/20241118010808.2243555-1-houtao@huaweicloud.com/
====================

Link: https://lore.kernel.org/all/20241206110622.1161752-1-houtao@huaweicloud.com/
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
matttbe pushed a commit that referenced this issue Dec 20, 2024
Its used from trace__run(), for the 'perf trace' live mode, i.e. its
strace-like, non-perf.data file processing mode, the most common one.

The trace__run() function will set trace->host using machine__new_host()
that is supposed to give a machine instance representing the running
machine, and since we'll use perf_env__arch_strerrno() to get the right
errno -> string table, we need to use machine->env, so initialize it in
machine__new_host().

Before the patch:

  (gdb) run trace --errno-summary -a sleep 1
  <SNIP>
   Summary of events:

   gvfs-afc-volume (3187), 2 events, 0.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     pselect6               1      0     0.000     0.000     0.000     0.000      0.00%

   GUsbEventThread (3519), 2 events, 0.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     poll                   1      0     0.000     0.000     0.000     0.000      0.00%
  <SNIP>
  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
  478		if (env->arch_strerrno == NULL)
  (gdb) bt
  #0  0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
  #1  0x00000000004b75d2 in thread__dump_stats (ttrace=0x14f58f0, trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4673
  #2  0x00000000004b78bf in trace__fprintf_thread (fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>, thread=0x10fa0b0, trace=0x7fffffffa5b0) at builtin-trace.c:4708
  #3  0x00000000004b7ad9 in trace__fprintf_thread_summary (trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4747
  #4  0x00000000004b656e in trace__run (trace=0x7fffffffa5b0, argc=2, argv=0x7fffffffde60) at builtin-trace.c:4456
  #5  0x00000000004ba43e in cmd_trace (argc=2, argv=0x7fffffffde60) at builtin-trace.c:5487
  #6  0x00000000004c0414 in run_builtin (p=0xec3068 <commands+648>, argc=5, argv=0x7fffffffde60) at perf.c:351
  #7  0x00000000004c06bb in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:404
  #8  0x00000000004c0814 in run_argv (argcp=0x7fffffffdc4c, argv=0x7fffffffdc40) at perf.c:448
  #9  0x00000000004c0b5d in main (argc=5, argv=0x7fffffffde60) at perf.c:560
  (gdb)

After:

  root@number:~# perf trace -a --errno-summary sleep 1
  <SNIP>
     pw-data-loop (2685), 1410 events, 16.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     epoll_wait           188      0   983.428     0.000     5.231    15.595      8.68%
     ioctl                 94      0     0.811     0.004     0.009     0.016      2.82%
     read                 188      0     0.322     0.001     0.002     0.006      5.15%
     write                141      0     0.280     0.001     0.002     0.018      8.39%
     timerfd_settime       94      0     0.138     0.001     0.001     0.007      6.47%

   gnome-control-c (179406), 1848 events, 20.9%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     poll                 222      0   959.577     0.000     4.322    21.414     11.40%
     recvmsg              150      0     0.539     0.001     0.004     0.013      5.12%
     write                300      0     0.442     0.001     0.001     0.007      3.29%
     read                 150      0     0.183     0.001     0.001     0.009      5.53%
     getpid               102      0     0.101     0.000     0.001     0.008      7.82%

  root@number:~#

Fixes: 54373b5 ("perf env: Introduce perf_env__arch_strerrno()")
Reported-by: Veronika Molnarova <vmolnaro@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Veronika Molnarova <vmolnaro@redhat.com>
Acked-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Michael Petlan <mpetlan@redhat.com>
Link: https://lore.kernel.org/r/Z0XffUgNSv_9OjOi@x1
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
matttbe pushed a commit that referenced this issue Dec 20, 2024
Ido Schimmel says:

====================
net: fib_rules: Add flow label selector support

In some deployments users would like to encode path information into
certain bits of the IPv6 flow label, the UDP source port and the DSCP
and use this information to route packets accordingly.

Redirecting traffic to a routing table based on the flow label is not
currently possible with Linux as FIB rules cannot match on it despite
the flow label being available in the IPv6 flow key.

This patchset extends FIB rules to match on the flow label with a mask.
Future patches will add mask attributes to L4 ports and DSCP matches.

Patches #1-#5 gradually extend FIB rules to match on the flow label.

Patches #6-#7 allow user space to specify a flow label in route get
requests. This is useful for both debugging and testing.

Patch #8 adjusts the fib6_table_lookup tracepoint to print the flow
label to the trace buffer for better observability.

Patch #9 extends the FIB rule selftest with flow label test cases while
utilizing the route get functionality from patch #6.
====================

Link: https://patch.msgid.link/20241216171201.274644-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
matttbe pushed a commit that referenced this issue Dec 24, 2024
Daniel Machon says:

====================
net: lan969x: add RGMII support

== Description:

This series is the fourth of a multi-part series, that prepares and adds
support for the new lan969x switch driver.

The upstreaming efforts is split into multiple series (might change a
bit as we go along):

        1) Prepare the Sparx5 driver for lan969x (merged)

        2) Add support for lan969x (same basic features as Sparx5
           provides excl. FDMA and VCAP, merged).

        3) Add lan969x VCAP functionality (merged).

    --> 4) Add RGMII support.

        5) Add FDMA support.

== RGMII support:

The lan969x switch device includes two RGMII port interfaces (port 28
and 29) supporting data speeds of 1 Gbps, 100 Mbps and 10 Mbps.

== Patch breakdown:

Patch #1 does some preparation work.

Patch #2 adds new function: is_port_rgmii() to the match data ops.

Patch #3 uses the is_port_rgmii() in a number of places.

Patch #4 makes sure that we do not configure an RGMII device as a
         low-speed device, when doing a port config.

Patch #5 makes sure we only return the PCS if the port mode requires
         it.

Patch #6 adds checks for RGMII PHY modes in sparx5_verify_speeds().

Patch #7 adds registers required to configure RGMII.

Patch #8 adds RGMII implementation.

Patch #9 documents RGMII delays in the dt-bindings.

Details are in the commit description of the individual patches

v4: https://lore.kernel.org/20241213-sparx5-lan969x-switch-driver-4-v4-0-d1a72c9c4714@microchip.com
v3: https://lore.kernel.org/20241118-sparx5-lan969x-switch-driver-4-v3-0-3cefee5e7e3a@microchip.com
v2: https://lore.kernel.org/20241113-sparx5-lan969x-switch-driver-4-v2-0-0db98ac096d1@microchip.com
v1: https://lore.kernel.org/20241106-sparx5-lan969x-switch-driver-4-v1-0-f7f7316436bd@microchip.com
====================

Link: https://patch.msgid.link/20241220-sparx5-lan969x-switch-driver-4-v5-0-fa8ba5dff732@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

No branches or pull requests

2 participants