Data Acknowledgement if single node is used #1

brodnev · 2018-06-21T18:26:31Z

The MPTCP uses Data Acknowledgement in order to retransmit data if one of the nodes fails permanently. Whatever, if there is only one (single) node between mptcp capable sender and mptcp capable receiver, does the Data Acknowledgement is still operating?

mjmartineau · 2018-06-21T18:41:08Z

@brodnev, for protocol questions like this I recommend either the multipath-tcp.org mailing list (https://listes-2.sipr.ucl.ac.be/sympa/info/mptcp-dev) for questions about the current Linux MPTCP implementation, or the Linux MPTCP upstreaming list at https://lists.01.org/mailman/listinfo/mptcp regarding the work-in-progress implementation in this github repo.

Running the following: # cd /sys/kernel/debug/tracing # echo 500000 > buffer_size_kb [ Or some other number that takes up most of memory ] # echo snapshot > events/sched/sched_switch/trigger Triggers the following bug: ------------[ cut here ]------------ kernel BUG at mm/slub.c:296! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:kfree+0x16c/0x180 Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246 RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80 RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500 RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00 FS: 00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0 Call Trace: event_trigger_callback+0xee/0x1d0 event_trigger_write+0xfc/0x1a0 __vfs_write+0x33/0x190 ? handle_mm_fault+0x115/0x230 ? _cond_resched+0x16/0x40 vfs_write+0xb0/0x190 ksys_write+0x52/0xc0 do_syscall_64+0x5a/0x160 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f363e16ab50 Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24 RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50 RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001 RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700 R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009 R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0 Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper 86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e ---[ end trace d301afa879ddfa25 ]--- The cause is because the register_snapshot_trigger() call failed to allocate the snapshot buffer, and then called unregister_trigger() which freed the data that was passed to it. Then on return to the function that called register_snapshot_trigger(), as it sees it failed to register, it frees the trigger_data again and causes a double free. By calling event_trigger_init() on the trigger_data (which only ups the reference counter for it), and then event_trigger_free() afterward, the trigger_data would not get freed by the registering trigger function as it would only up and lower the ref count for it. If the register trigger function fails, then the event_trigger_free() called after it will free the trigger data normally. Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home Cc: stable@vger.kerne.org Fixes: 93e31ff ("tracing: Add 'snapshot' event trigger command") Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

The number of eRPs that can be used by a single A-TCAM region is limited to 16. When more eRPs are needed, an ordinary circuit TCAM (C-TCAM) can be used to hold the extra eRPs. Unlike the A-TCAM, only a single (last) lookup is performed in the C-TCAM and not a lookup per-eRP. However, modeling the C-TCAM as extra eRPs will allow us to easily introduce support for pruning in a follow-up patch set and is also logically correct. The following diagram depicts the relation between both TCAMs: C-TCAM +-------------------+ +--------------------+ +-----------+ | | | | | | | eRP #1 (A-TCAM) +----> ... +----+ eRP #16 (A-TCAM) +----+ eRP #17 | | | | | | ... | +-------------------+ +--------------------+ | eRP #N | | | +-----------+ Lookup order is from left to right. Extend the eRP core APIs with a C-TCAM parameter which indicates whether the requested eRP is to be used with the C-TCAM or not. Since the C-TCAM is only meant to absorb rules that can't fit in the A-TCAM due to exceeded number of eRPs or key collision, an error is returned when a C-TCAM eRP needs to be created when the eRP state machine is in its initial state (i.e., 'no masks'). This should only happen in the face of very unlikely errors when trying to push rules into the A-TCAM. In order not to perform unnecessary lookups, the eRP core will only enable a C-TCAM lookup for a given region if it knows there are C-TCAM eRPs present. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>

Registration of a memory region(MR) through FRMR/fastreg(unlike FMR) needs a connection/qp. With a proxy qp, this dependency on connection will be removed, but that needs more infrastructure patches, which is a work in progress. As an intermediate fix, the get_mr returns EOPNOTSUPP when connection details are not populated. The MR registration through sendmsg() will continue to work even with fast registration, since connection in this case is formed upfront. This patch fixes the following crash: kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Modules linked in: CPU: 1 PID: 4244 Comm: syzkaller468044 Not tainted 4.16.0-rc6+ #361 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rds_ib_get_mr+0x5c/0x230 net/rds/ib_rdma.c:544 RSP: 0018:ffff8801b059f890 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff8801b07e1300 RCX: ffffffff8562d96e RDX: 000000000000000d RSI: 0000000000000001 RDI: 0000000000000068 RBP: ffff8801b059f8b8 R08: ffffed0036274244 R09: ffff8801b13a1200 R10: 0000000000000004 R11: ffffed0036274243 R12: ffff8801b13a1200 R13: 0000000000000001 R14: ffff8801ca09fa9c R15: 0000000000000000 FS: 00007f4d050af700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4d050aee78 CR3: 00000001b0d9b006 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __rds_rdma_map+0x710/0x1050 net/rds/rdma.c:271 rds_get_mr_for_dest+0x1d4/0x2c0 net/rds/rdma.c:357 rds_setsockopt+0x6cc/0x980 net/rds/af_rds.c:347 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4456d9 RSP: 002b:00007f4d050aedb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 00000000004456d9 RDX: 0000000000000007 RSI: 0000000000000114 RDI: 0000000000000004 RBP: 00000000006dac38 R08: 00000000000000a0 R09: 0000000000000000 R10: 0000000020000380 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffbfb36d6f R14: 00007f4d050af9c0 R15: 0000000000000005 Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 cc 01 00 00 4c 8b bb 80 04 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7f 68 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9c 01 00 00 4d 8b 7f 68 48 b8 00 00 00 00 00 RIP: rds_ib_get_mr+0x5c/0x230 net/rds/ib_rdma.c:544 RSP: ffff8801b059f890 ---[ end trace 7e1cea13b85473b0 ]--- Reported-by: syzbot+b51c77ef956678a65834@syzkaller.appspotmail.com Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by: Avinash Repaka <avinash.repaka@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>

@p-

…ilure While forking, if delayacct init fails due to memory shortage, it continues expecting all delayacct users to check task->delays pointer against NULL before dereferencing it, which all of them used to do. Commit c96f547 ("delayacct: Account blkio completion on the correct task"), while updating delayacct_blkio_end() to take the target task instead of always using %current, made the function test NULL on %current->delays and then continue to operated on @p->delays. If %current succeeded init while @p didn't, it leads to the following crash. BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 IP: __delayacct_blkio_end+0xc/0x40 PGD 8000001fd07e1067 P4D 8000001fd07e1067 PUD 1fcffbb067 PMD 0 Oops: 0000 [#1] SMP PTI CPU: 4 PID: 25774 Comm: QIOThread0 Not tainted 4.16.0-9_fbk1_rc2_1180_g6b593215b4d7 #9 RIP: 0010:__delayacct_blkio_end+0xc/0x40 Call Trace: try_to_wake_up+0x2c0/0x600 autoremove_wake_function+0xe/0x30 __wake_up_common+0x74/0x120 wake_up_page_bit+0x9c/0xe0 mpage_end_io+0x27/0x70 blk_update_request+0x78/0x2c0 scsi_end_request+0x2c/0x1e0 scsi_io_completion+0x20b/0x5f0 blk_mq_complete_request+0xa2/0x100 ata_scsi_qc_complete+0x79/0x400 ata_qc_complete_multiple+0x86/0xd0 ahci_handle_port_interrupt+0xc9/0x5c0 ahci_handle_port_intr+0x54/0xb0 ahci_single_level_irq_intr+0x3b/0x60 __handle_irq_event_percpu+0x43/0x190 handle_irq_event_percpu+0x20/0x50 handle_irq_event+0x2a/0x50 handle_edge_irq+0x80/0x1c0 handle_irq+0xaf/0x120 do_IRQ+0x41/0xc0 common_interrupt+0xf/0xf Fix it by updating delayacct_blkio_end() check @p->delays instead. Link: http://lkml.kernel.org/r/20180724175542.GP1934745@devbig577.frc2.facebook.com Fixes: c96f547 ("delayacct: Account blkio completion on the correct task") Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Dave Jones <dsj@fb.com> Debugged-by: Dave Jones <dsj@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Josh Snyder <joshs@netflix.com> Cc: <stable@vger.kernel.org> [4.15+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vma_is_anonymous() relies on ->vm_ops being NULL to detect anonymous VMA. This is unreliable as ->mmap may not set ->vm_ops. False-positive vma_is_anonymous() may lead to crashes: next ffff8801ce5e7040 prev ffff8801d20eca50 mm ffff88019c1e13c0 prot 27 anon_vma ffff88019680cdd8 vm_ops 0000000000000000 pgoff 0 file ffff8801b2ec2d00 private_data 0000000000000000 flags: 0xff(read|write|exec|shared|mayread|maywrite|mayexec|mayshare) ------------[ cut here ]------------ kernel BUG at mm/memory.c:1422! invalid opcode: 0000 [#1] SMP KASAN CPU: 0 PID: 18486 Comm: syz-executor3 Not tainted 4.18.0-rc3+ #136 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:zap_pmd_range mm/memory.c:1421 [inline] RIP: 0010:zap_pud_range mm/memory.c:1466 [inline] RIP: 0010:zap_p4d_range mm/memory.c:1487 [inline] RIP: 0010:unmap_page_range+0x1c18/0x2220 mm/memory.c:1508 Call Trace: unmap_single_vma+0x1a0/0x310 mm/memory.c:1553 zap_page_range_single+0x3cc/0x580 mm/memory.c:1644 unmap_mapping_range_vma mm/memory.c:2792 [inline] unmap_mapping_range_tree mm/memory.c:2813 [inline] unmap_mapping_pages+0x3a7/0x5b0 mm/memory.c:2845 unmap_mapping_range+0x48/0x60 mm/memory.c:2880 truncate_pagecache+0x54/0x90 mm/truncate.c:800 truncate_setsize+0x70/0xb0 mm/truncate.c:826 simple_setattr+0xe9/0x110 fs/libfs.c:409 notify_change+0xf13/0x10f0 fs/attr.c:335 do_truncate+0x1ac/0x2b0 fs/open.c:63 do_sys_ftruncate+0x492/0x560 fs/open.c:205 __do_sys_ftruncate fs/open.c:215 [inline] __se_sys_ftruncate fs/open.c:213 [inline] __x64_sys_ftruncate+0x59/0x80 fs/open.c:213 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Reproducer: #include <stdio.h> #include <stddef.h> #include <stdint.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <unistd.h> #include <fcntl.h> #define KCOV_INIT_TRACE _IOR('c', 1, unsigned long) #define KCOV_ENABLE _IO('c', 100) #define KCOV_DISABLE _IO('c', 101) #define COVER_SIZE (1024<<10) #define KCOV_TRACE_PC 0 #define KCOV_TRACE_CMP 1 int main(int argc, char **argv) { int fd; unsigned long *cover; system("mount -t debugfs none /sys/kernel/debug"); fd = open("/sys/kernel/debug/kcov", O_RDWR); ioctl(fd, KCOV_INIT_TRACE, COVER_SIZE); cover = mmap(NULL, COVER_SIZE * sizeof(unsigned long), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); munmap(cover, COVER_SIZE * sizeof(unsigned long)); cover = mmap(NULL, COVER_SIZE * sizeof(unsigned long), PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); memset(cover, 0, COVER_SIZE * sizeof(unsigned long)); ftruncate(fd, 3UL << 20); return 0; } This can be fixed by assigning anonymous VMAs own vm_ops and not relying on it being NULL. If ->mmap() failed to set ->vm_ops, mmap_region() will set it to dummy_vm_ops. This way we will have non-NULL ->vm_ops for all VMAs. Link: http://lkml.kernel.org/r/20180724121139.62570-4-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: syzbot+3f84280d52be9b7083cc@syzkaller.appspotmail.com Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Ido Schimmel says: ==================== mlxsw: Support DSCP prioritization and rewrite Petr says: On ingress, a network device such as a switch assigns to packets priority based on various criteria. Common options include interpreting PCP and DSCP fields according to user configuration. When a packet egresses the switch, a reverse process may rewrite PCP and/or DSCP headers according to packet priority. So far, mlxsw has supported prioritization based on PCP (802.1p priority tag). This patch set introduces support for prioritization based on DSCP, and DSCP rewrite. To configure the DSCP-to-priority maps, the user is expected to invoke ieee_setapp and ieee_delapp DCBNL ops, e.g. by using lldptool: To decide whether or not to pay attention to DSCP values, the Spectrum switch recognize a per-port configuration of trust level. Until the first APP rule is added for a given port, this port's trust level stays at PCP, meaning that PCP is used for packet prioritization. With the first DSCP APP rule, the port is configured to trust DSCP instead, and it stays there until all DSCP APP rules are removed again. Besides the DSCP (value 5) selector, another selector that plays into packet prioritization is Ethernet type (value 1) with PID of 0. Such APP entries denote default priority[1]: With this patch set, mlxsw uses these values to configure priority for DSCP values not explicitly specified in DSCP APP map. In the future we expect to also use this to configure default port priority for untagged packets. Access to DSCP-to-priority map, priority-to-DSCP map, and default priority for a port is exposed through three new DCB helpers. Like the already-existing dcb_ieee_getapp_mask() helper, these helpers operate in terms of bitmaps, to support the arbitrary M:N mapping that the APP rules allow. Such interface presents all the relevant information from the APP database without necessitating exposition of iterators, locking or other complex primitives. It is up to the driver to then digest the mapping in a way that the device supports. In this patch set, mlxsw resolves conflicts by favoring higher-numbered DSCP values and priorities. In this patchset: - Patch #1 fixes a bug in DCB APP database management. - Patch #2 adds the getters described above. - Patches #3-#6 add Spectrum configuration registers. - Patch #7 adds the mlxsw logic that configures the device according to APP rules. - Patch #8 adds a self-test. The test is added to the subdirectory drivers/net/mlxsw. Even though it's not particularly specific to mlxsw, it's not suitable for running on soft devices (which don't support the ieee_getapp et.al.), and thus isn't a good fit for the general net/forwarding directory. [1] 802.1Q-2014, Table D-9 ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

bpf_parse_prog() is protected by rcu_read_lock(). so that GFP_KERNEL is not allowed in the bpf_parse_prog(). [51015.579396] ============================= [51015.579418] WARNING: suspicious RCU usage [51015.579444] 4.18.0-rc6+ #208 Not tainted [51015.579464] ----------------------------- [51015.579488] ./include/linux/rcupdate.h:303 Illegal context switch in RCU read-side critical section! [51015.579510] other info that might help us debug this: [51015.579532] rcu_scheduler_active = 2, debug_locks = 1 [51015.579556] 2 locks held by ip/1861: [51015.579577] #0: 00000000a8c12fd1 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x2e0/0x910 [51015.579711] #1: 00000000bf815f8e (rcu_read_lock){....}, at: lwtunnel_build_state+0x96/0x390 [51015.579842] stack backtrace: [51015.579869] CPU: 0 PID: 1861 Comm: ip Not tainted 4.18.0-rc6+ #208 [51015.579891] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015 [51015.579911] Call Trace: [51015.579950] dump_stack+0x74/0xbb [51015.580000] ___might_sleep+0x16b/0x3a0 [51015.580047] __kmalloc_track_caller+0x220/0x380 [51015.580077] kmemdup+0x1c/0x40 [51015.580077] bpf_parse_prog+0x10e/0x230 [51015.580164] ? kasan_kmalloc+0xa0/0xd0 [51015.580164] ? bpf_destroy_state+0x30/0x30 [51015.580164] ? bpf_build_state+0xe2/0x3e0 [51015.580164] bpf_build_state+0x1bb/0x3e0 [51015.580164] ? bpf_parse_prog+0x230/0x230 [51015.580164] ? lock_is_held_type+0x123/0x1a0 [51015.580164] lwtunnel_build_state+0x1aa/0x390 [51015.580164] fib_create_info+0x1579/0x33d0 [51015.580164] ? sched_clock_local+0xe2/0x150 [51015.580164] ? fib_info_update_nh_saddr+0x1f0/0x1f0 [51015.580164] ? sched_clock_local+0xe2/0x150 [51015.580164] fib_table_insert+0x201/0x1990 [51015.580164] ? lock_downgrade+0x610/0x610 [51015.580164] ? fib_table_lookup+0x1920/0x1920 [51015.580164] ? lwtunnel_valid_encap_type.part.6+0xcb/0x3a0 [51015.580164] ? rtm_to_fib_config+0x637/0xbd0 [51015.580164] inet_rtm_newroute+0xed/0x1b0 [51015.580164] ? rtm_to_fib_config+0xbd0/0xbd0 [51015.580164] rtnetlink_rcv_msg+0x331/0x910 [ ... ] Fixes: 3a0af8f ("bpf: BPF for lightweight tunnel infrastructure") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Kernel panic when with high memory pressure, calltrace looks like, PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java" #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc #6 [ffff881ec7ed7838] __node_set at ffffffff81680300 #7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f #8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5 #9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8 [exception RIP: _raw_spin_lock_irqsave+47] RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8 RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008 RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098 R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 It happens in the pagefault and results in double pagefault during compacting pages when memory allocation fails. Analysed the vmcore, the page leads to second pagefault is corrupted with _mapcount=-256, but private=0. It's caused by the race between migration and ballooning, and lock missing in virtballoon_migratepage() of virtio_balloon driver. This patch fix the bug. Fixes: e225042 ("virtio_balloon: introduce migration primitives to balloon pages") Cc: stable@vger.kernel.org Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn> Signed-off-by: Huang Chong <huang.chong@zte.com.cn> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Petr Machata says: ==================== A test for mirror-to-gretap with team in UL packet path This patchset adds a test for "tc action mirred mirror" where the mirrored-to device is a gretap, and underlay path contains a team device. In patch #1 require_command() is added, which should henceforth be used to declare dependence on a certain tool. In patch #2, two new functions, team_create() and team_destroy(), are added to lib.sh. The newly-added test uses arping, which isn't necessarily available. Therefore patch #3 introduces $ARPING, and a preexisting test is fixed to require_command $ARPING. In patches #4 and #5, two new tests are added. In both cases, a team device is on egress path of a mirrored packet in a mirror-to-gretap scenario. In the first one, the team device is in loadbalance mode, in the second one it's in lacp mode. (The difference in modes necessitates a different testing strategy, hence two test cases instead of just parameterizing one.) ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot found that the following sequence produces a LOCKDEP splat [1] ip link add bond10 type bond ip link add bond11 type bond ip link set bond11 master bond10 To fix this, we can use the already provided nest_level. This patch also provides correct nesting for dev->addr_list_lock [1] WARNING: possible recursive locking detected 4.18.0-rc6+ #167 Not tainted -------------------------------------------- syz-executor751/4439 is trying to acquire lock: (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline] (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426 but task is already holding lock: (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline] (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&bond->stats_lock)->rlock); lock(&(&bond->stats_lock)->rlock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by syz-executor751/4439: #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 #1: (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline] #1: (____ptrval____) (&(&bond->stats_lock)->rlock){+.+.}, at: bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426 #2: (____ptrval____) (rcu_read_lock){....}, at: bond_get_stats+0x0/0x560 include/linux/compiler.h:215 stack backtrace: CPU: 0 PID: 4439 Comm: syz-executor751 Not tainted 4.18.0-rc6+ #167 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 print_deadlock_bug kernel/locking/lockdep.c:1765 [inline] check_deadlock kernel/locking/lockdep.c:1809 [inline] validate_chain kernel/locking/lockdep.c:2405 [inline] __lock_acquire.cold.64+0x1fb/0x486 kernel/locking/lockdep.c:3435 lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144 spin_lock include/linux/spinlock.h:310 [inline] bond_get_stats+0xb4/0x560 drivers/net/bonding/bond_main.c:3426 dev_get_stats+0x10f/0x470 net/core/dev.c:8316 bond_get_stats+0x232/0x560 drivers/net/bonding/bond_main.c:3432 dev_get_stats+0x10f/0x470 net/core/dev.c:8316 rtnl_fill_stats+0x4d/0xac0 net/core/rtnetlink.c:1169 rtnl_fill_ifinfo+0x1aa6/0x3fb0 net/core/rtnetlink.c:1611 rtmsg_ifinfo_build_skb+0xc8/0x190 net/core/rtnetlink.c:3268 rtmsg_ifinfo_event.part.30+0x45/0xe0 net/core/rtnetlink.c:3300 rtmsg_ifinfo_event net/core/rtnetlink.c:3297 [inline] rtnetlink_event+0x144/0x170 net/core/rtnetlink.c:4716 notifier_call_chain+0x180/0x390 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735 call_netdevice_notifiers net/core/dev.c:1753 [inline] netdev_features_change net/core/dev.c:1321 [inline] netdev_change_features+0xb3/0x110 net/core/dev.c:7759 bond_compute_features.isra.47+0x585/0xa50 drivers/net/bonding/bond_main.c:1120 bond_enslave+0x1b25/0x5da0 drivers/net/bonding/bond_main.c:1755 bond_do_ioctl+0x7cb/0xae0 drivers/net/bonding/bond_main.c:3528 dev_ifsioc+0x43c/0xb30 net/core/dev_ioctl.c:327 dev_ioctl+0x1b5/0xcc0 net/core/dev_ioctl.c:493 sock_do_ioctl+0x1d3/0x3e0 net/socket.c:992 sock_ioctl+0x30d/0x680 net/socket.c:1093 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:684 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 __do_sys_ioctl fs/ioctl.c:708 [inline] __se_sys_ioctl fs/ioctl.c:706 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440859 Code: e8 2c af 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc51a92878 EFLAGS: 00000213 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440859 RDX: 0000000020000040 RSI: 0000000000008990 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000022d5880 R11: 0000000000000213 R12: 0000000000007390 R13: 0000000000401db0 R14: 0000000000000000 R15: 0000000000000000 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jay Vosburgh <j.vosburgh@gmail.com> Cc: Veaceslav Falico <vfalico@gmail.com> Cc: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: David S. Miller <davem@davemloft.net>

Petr Machata says: ==================== ipv4: Control SKB reprioritization after forwarding After IPv4 packets are forwarded, the priority of the corresponding SKB is updated according to the TOS field of IPv4 header. This overrides any prioritization done earlier by e.g. an skbedit action or ingress-qos-map defined at a vlan device. Such overriding may not always be desirable. Even if the packet ends up being routed, which implies this is an L3 network node, an administrator may wish to preserve whatever prioritization was done earlier on in the pipeline. Therefore this patch set introduces a sysctl that controls this behavior, net.ipv4.ip_forward_update_priority. It's value is 1 by default to preserve the current behavior. All of the above is implemented in patch #1. Value changes prompt a new NETEVENT_IPV4_FWD_UPDATE_PRIORITY_UPDATE notification, so that the drivers can hook up whatever logic may depend on this value. That is implemented in patch #2. In patches #3 and #4, mlxsw is adapted to recognize the sysctl. On initialization, the RGCR register that handles router configuration is set in accordance with the sysctl. The new notification is listened to and RGCR is reconfigured as necessary. In patches #5 to #7, a selftest is added to verify that mlxsw reflects the sysctl value as necessary. The test is expressed in terms of the recently-introduced ieee_setapp support, and works by observing how DSCP value gets rewritten depending on packet priority. For this reason, the test is added to the subdirectory drivers/net/mlxsw. Even though it's not particularly specific to mlxsw, it's not suitable for running on soft devices (which don't support the ieee_setapp et.al.). Changes from v1 to v2: - In patch #1, init sysctl_ip_fwd_update_priority to 1 instead of true. Changes from RFC to v1: - Fix wrong sysctl name in ip-sysctl.txt - Add notifications - Add mlxsw support - Add self test ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Amit Pundir and Youling in parallel reported crashes with recent mainline kernels running Android: F DEBUG : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** F DEBUG : Build fingerprint: 'Android/db410c32_only/db410c32_only:Q/OC-MR1/102:userdebug/test-key F DEBUG : Revision: '0' F DEBUG : ABI: 'arm' F DEBUG : pid: 2261, tid: 2261, name: zygote >>> zygote <<< F DEBUG : signal 7 (SIGBUS), code 2 (BUS_ADRERR), fault addr 0xec00008 ... <snip> ... F DEBUG : backtrace: F DEBUG : #00 pc 00001c04 /system/lib/libc.so (memset+48) F DEBUG : #1 pc 0010c513 /system/lib/libart.so (create_mspace_with_base+82) F DEBUG : #2 pc 0015c601 /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateMspace(void*, unsigned int, unsigned int)+40) F DEBUG : #3 pc 0015c3ed /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateFromMemMap(art::MemMap*, std::__1::basic_string<char, std::__ 1::char_traits<char>, std::__1::allocator<char>> const&, unsigned int, unsigned int, unsigned int, unsigned int, bool)+36) ... This was bisected back to commit bfd40ea ("mm: fix vma_is_anonymous() false-positives"). create_mspace_with_base() in the trace above, utilizes ashmem, and with ashmem, for shared mappings we use shmem_zero_setup(), which sets the vma->vm_ops to &shmem_vm_ops. But for private ashmem mappings nothing sets the vma->vm_ops. Looking at the problematic patch, it seems to add a requirement that one call vma_set_anonymous() on a vma, otherwise the dummy_vm_ops will be used. Using the dummy_vm_ops seem to triggger SIGBUS when traversing unmapped pages. Thus, this patch adds a call to vma_set_anonymous() for ashmem private mappings and seems to avoid the reported problem. Fixes: bfd40ea ("mm: fix vma_is_anonymous() false-positives") Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Colin Cross <ccross@google.com> Cc: Matthew Wilcox <willy@infradead.org> Reported-by: Amit Pundir <amit.pundir@linaro.org> Reported-by: Youling 257 <youling257@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add the following verifier tests to cover the cgroup storage functionality: 1) valid access to the cgroup storage 2) invalid access: use regular hashmap instead of cgroup storage map 3) invalid access: use invalid map fd 4) invalid access: try access memory after the cgroup storage 5) invalid access: try access memory before the cgroup storage 6) invalid access: call get_local_storage() with non-zero flags For tests 2)-6) check returned error strings. Expected output: $ ./test_verifier #0/u add+sub+mul OK #0/p add+sub+mul OK #1/u DIV32 by 0, zero check 1 OK ... #280/p valid cgroup storage access OK #281/p invalid cgroup storage access 1 OK #282/p invalid cgroup storage access 2 OK #283/p invalid per-cgroup storage access 3 OK #284/p invalid cgroup storage access 4 OK #285/p invalid cgroup storage access 5 OK ... #649/p pass modified ctx pointer to helper, 2 OK #650/p pass modified ctx pointer to helper, 3 OK Summary: 901 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Guillaume Nault says: ==================== l2tp: sanitise MTU handling on sessions Most of the code handling sessions' MTU has no effect. The ->mtu field in struct l2tp_session might be used at session creation time, but neither PPP nor Ethernet pseudo-wires take updates into account. L2TP sessions don't have a concept of MTU, which is the reason why ->mtu is mostly ignored. MTU should remain a network device thing. Therefore this patch set does not try to propagate/update ->mtu to/from the device. That would complicate the code unnecessarily. Instead this field and the associated ioctl commands and netlink attributes are removed. Patch #1 defines l2tp_tunnel_dst_mtu() in order to simplify the following patches. Then patches #2 and #3 remove MTU handling from PPP and Ethernet pseudo-wires respectively. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says: ==================== mlxsw: Enable MC-aware mode for mlxsw ports Petr says: Due to an issue in Spectrum chips, when unicast traffic shares the same queue as BUM traffic, and there is a congestion, the BUM traffic is admitted to the queue anyway, thus pushing out all UC traffic. In order to give unicast traffic precedence over BUM traffic, configure multicast-aware mode on all ports. Under multicast-aware regime, when assigning traffic class to a packet, the switch doesn't merely take the value prescribed by the QTCT register. For BUM traffic, it instead assigns that value plus 8. That limits the number of available TCs, but since mlxsw currently only uses the lower eight anyway, it is no real loss. The two TCs (UC and MC one) are then mapped to the same subgroup and strictly prioritized so that UC traffic is preferred in case of congestion. In patch #1, introduce a new register, QTCTM, which enables the multicast-aware mode. In patch #2, fix a typo in related code. In patch #3, set up TCs and QTCTM to enable multicast-aware mode. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>

The shift of 'cwnd' with '(now - hc->tx_lsndtime) / hc->tx_rto' value can lead to undefined behavior [1]. In order to fix this use a gradual shift of the window with a 'while' loop, similar to what tcp_cwnd_restart() is doing. When comparing delta and RTO there is a minor difference between TCP and DCCP, the last one also invokes dccp_cwnd_restart() and reduces 'cwnd' if delta equals RTO. That case is preserved in this change. [1]: [40850.963623] UBSAN: Undefined behaviour in net/dccp/ccids/ccid2.c:237:7 [40851.043858] shift exponent 67 is too large for 32-bit type 'unsigned int' [40851.127163] CPU: 3 PID: 15940 Comm: netstress Tainted: G W E 4.18.0-rc7.x86_64 #1 ... [40851.377176] Call Trace: [40851.408503] dump_stack+0xf1/0x17b [40851.451331] ? show_regs_print_info+0x5/0x5 [40851.503555] ubsan_epilogue+0x9/0x7c [40851.548363] __ubsan_handle_shift_out_of_bounds+0x25b/0x2b4 [40851.617109] ? __ubsan_handle_load_invalid_value+0x18f/0x18f [40851.686796] ? xfrm4_output_finish+0x80/0x80 [40851.739827] ? lock_downgrade+0x6d0/0x6d0 [40851.789744] ? xfrm4_prepare_output+0x160/0x160 [40851.845912] ? ip_queue_xmit+0x810/0x1db0 [40851.895845] ? ccid2_hc_tx_packet_sent+0xd36/0x10a0 [dccp] [40851.963530] ccid2_hc_tx_packet_sent+0xd36/0x10a0 [dccp] [40852.029063] dccp_xmit_packet+0x1d3/0x720 [dccp] [40852.086254] dccp_write_xmit+0x116/0x1d0 [dccp] [40852.142412] dccp_sendmsg+0x428/0xb20 [dccp] [40852.195454] ? inet_dccp_listen+0x200/0x200 [dccp] [40852.254833] ? sched_clock+0x5/0x10 [40852.298508] ? sched_clock+0x5/0x10 [40852.342194] ? inet_create+0xdf0/0xdf0 [40852.388988] sock_sendmsg+0xd9/0x160 ... Fixes: 113ced1 ("dccp ccid-2: Perform congestion-window validation") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>

The definition of static_key_slow_inc() has cpus_read_lock in place. In the virtio_net driver, XPS queues are initialized after setting the queue:cpu affinity in virtnet_set_affinity() which is already protected within cpus_read_lock. Lockdep prints a warning when we are trying to acquire cpus_read_lock when it is already held. This patch adds an ability to call __netif_set_xps_queue under cpus_read_lock(). Acked-by: Jason Wang <jasowang@redhat.com> ============================================ WARNING: possible recursive locking detected 4.18.0-rc3-next-20180703+ #1 Not tainted -------------------------------------------- swapper/0/1 is trying to acquire lock: 00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_inc+0xe/0x20 but task is already holding lock: 00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: init_vqs+0x513/0x5a0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(cpu_hotplug_lock.rw_sem); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by swapper/0/1: #0: 00000000244bc7da (&dev->mutex){....}, at: __driver_attach+0x5a/0x110 #1: 00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: init_vqs+0x513/0x5a0 #2: 000000005cd8463f (xps_map_mutex){+.+.}, at: __netif_set_xps_queue+0x8d/0xc60 v2: move cpus_read_lock() out of __netif_set_xps_queue() Cc: "Nambiar, Amritha" <amritha.nambiar@intel.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Fixes: 8af2c06 ("net-sysfs: Add interface for Rx queue(s) map per Tx queue") Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>

…_read Subflows can get removed from under our feet, thus we might be iterating on garbage here. That can panic like: [52899.160112] BUG: unable to handle kernel NULL pointer dereference at (null) [52899.160157] IP: tcp_splice_read+0x225/0x330 [52899.160166] PGD 8000000164ff8067 P4D 8000000164ff8067 PUD 163d67067 PMD 0 [52899.160189] Oops: 0000 [#1] SMP PTI [52899.160198] Modules linked in: binfmt_misc xt_REDIRECT nf_nat_redirect xt_statistic xt_mark ipt_MASQUERADE nf_nat_masquerade_ipv4 xt_connmark xt_nat xt_comment xt_geoip(O) xt_conntrack iptable_mangle iptable_nat nf_nat_ipv4 nf_nat iptable_filter sch_fq_codel nf_conntrack_tftp nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack_proto_gre nf_conntrack_irc nf_conntrack_ftp nf_conntrack pcspkr tun it87 hwmon_vid vfat fat x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel crypto_simd glue_helper cryptd iTCO_wdt i2c_designware_platform iTCO_vendor_support i2c_designware_core intel_cstate intel_rapl_perf idma64 i2c_i801 sg virt_dma pinctrl_sunrisepoint wmi pinctrl_intel acpi_pad intel_lpss_pci intel_lpss mei_me pcc_cpufreq [52899.160410] mfd_core intel_pch_thermal mei shpchp ip_tables xfs libcrc32c sd_mod crc32c_intel igb ptp sdhci_pci pps_core sdhci dca i915 ahci i2c_algo_bit mmc_core libahci drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops libata drm video [last unloaded: pcspkr] [52899.160495] CPU: 0 PID: 21938 Comm: redsocks Tainted: G O 4.14.64+ #1 [52899.160506] Hardware name: Default string Default string/Default string, BIOS 5.12 07/01/2018 [52899.160518] task: ffff880164d45e00 task.stack: ffffc90002824000 [52899.160536] RIP: 0010:tcp_splice_read+0x225/0x330 [52899.160546] RSP: 0018:ffffc90002827dd8 EFLAGS: 00010286 [52899.160558] RAX: 0000000000000000 RBX: ffff88015b965280 RCX: 0000000000100000 [52899.160569] RDX: ffff88015ba30180 RSI: ffffc90002827ee8 RDI: ffff8801164d82c0 [52899.160579] RBP: ffffc90002827e50 R08: 00000000ffffffff R09: 0000000000000000 [52899.160589] R10: ffff880163940f00 R11: ffff88015ba30180 R12: ffff8801164d82c0 [52899.160599] R13: ffff88015ba30180 R14: ffffc90002827ee8 R15: 0000000000000003 [52899.160611] FS: 00007fae07922740(0000) GS:ffff88016ec00000(0000) knlGS:0000000000000000 [52899.160624] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [52899.160634] CR2: 0000000000000000 CR3: 0000000164c9a006 CR4: 00000000003606f0 [52899.160646] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [52899.160656] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [52899.160664] Call Trace: [52899.160684] ? kmem_cache_free+0x1aa/0x1c0 [52899.160702] sock_splice_read+0x25/0x30 [52899.160719] do_splice_to+0x76/0x90 [52899.160735] SyS_splice+0x6fd/0x750 [52899.160750] ? syscall_trace_enter+0x1cd/0x2b0 [52899.160766] do_syscall_64+0x79/0x1b0 [52899.160784] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 [52899.160795] RIP: 0033:0x7fae07213493 [52899.160804] RSP: 002b:00007fff48ffdfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [52899.160819] RAX: ffffffffffffffda RBX: 00007fff48ffe040 RCX: 00007fae07213493 [52899.160829] RDX: 000000000000008b RSI: 0000000000000000 RDI: 0000000000000081 [52899.160839] RBP: 0000000000000081 R08: 0000000000100000 R09: 0000000000000003 [52899.160849] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002214d40 [52899.160859] R13: 0000000000000081 R14: 0000000000000002 R15: 00000000022124f0 [52899.160870] Code: ff ff 48 8b 83 d0 07 00 00 48 8b 00 48 85 c0 0f 84 33 fe ff ff 44 8b 05 7a eb d3 00 41 f7 d0 0f 1f 44 00 00 48 8b 80 e8 07 00 00 <48> 8b 00 48 85 c0 75 ec e9 10 fe ff ff 0f b6 43 12 3c 01 0f 85 [52899.161029] RIP: tcp_splice_read+0x225/0x330 RSP: ffffc90002827dd8 [52899.161038] CR2: 0000000000000000 Github-issue: multipath-tcp/mptcp#279 Fixes: ee4f8f6 ("Support tcp_read_sock") Reported-by: https://github.com/wapsi Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> (cherry picked from commit 80671d2) Signed-off-by: Christoph Paasch <cpaasch@apple.com>

A kernel crash occurrs when defragmented packet is fragmented in ip_do_fragment(). In defragment routine, skb_orphan() is called and skb->ip_defrag_offset is set. but skb->sk and skb->ip_defrag_offset are same union member. so that frag->sk is not NULL. Hence crash occurrs in skb->sk check routine in ip_do_fragment() when defragmented packet is fragmented. test commands: %iptables -t nat -I POSTROUTING -j MASQUERADE %hping3 192.168.4.2 -s 1000 -p 2000 -d 60000 splat looks like: [ 261.069429] kernel BUG at net/ipv4/ip_output.c:636! [ 261.075753] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 261.083854] CPU: 1 PID: 1349 Comm: hping3 Not tainted 4.19.0-rc2+ #3 [ 261.100977] RIP: 0010:ip_do_fragment+0x1613/0x2600 [ 261.106945] Code: e8 e2 38 e3 fe 4c 8b 44 24 18 48 8b 74 24 08 e9 92 f6 ff ff 80 3c 02 00 0f 85 da 07 00 00 48 8b b5 d0 00 00 00 e9 25 f6 ff ff <0f> 0b 0f 0b 44 8b 54 24 58 4c 8b 4c 24 18 4c 8b 5c 24 60 4c 8b 6c [ 261.127015] RSP: 0018:ffff8801031cf2c0 EFLAGS: 00010202 [ 261.134156] RAX: 1ffff1002297537b RBX: ffffed0020639e6e RCX: 0000000000000004 [ 261.142156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880114ba9bd8 [ 261.150157] RBP: ffff880114ba8a40 R08: ffffed0022975395 R09: ffffed0022975395 [ 261.158157] R10: 0000000000000001 R11: ffffed0022975394 R12: ffff880114ba9ca4 [ 261.166159] R13: 0000000000000010 R14: ffff880114ba9bc0 R15: dffffc0000000000 [ 261.174169] FS: 00007fbae2199700(0000) GS:ffff88011b400000(0000) knlGS:0000000000000000 [ 261.183012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 261.189013] CR2: 00005579244fe000 CR3: 0000000119bf4000 CR4: 00000000001006e0 [ 261.198158] Call Trace: [ 261.199018] ? dst_output+0x180/0x180 [ 261.205011] ? save_trace+0x300/0x300 [ 261.209018] ? ip_copy_metadata+0xb00/0xb00 [ 261.213034] ? sched_clock_local+0xd4/0x140 [ 261.218158] ? kill_l4proto+0x120/0x120 [nf_conntrack] [ 261.223014] ? rt_cpu_seq_stop+0x10/0x10 [ 261.227014] ? find_held_lock+0x39/0x1c0 [ 261.233008] ip_finish_output+0x51d/0xb50 [ 261.237006] ? ip_fragment.constprop.56+0x220/0x220 [ 261.243011] ? nf_ct_l4proto_register_one+0x5b0/0x5b0 [nf_conntrack] [ 261.250152] ? rcu_is_watching+0x77/0x120 [ 261.255010] ? nf_nat_ipv4_out+0x1e/0x2b0 [nf_nat_ipv4] [ 261.261033] ? nf_hook_slow+0xb1/0x160 [ 261.265007] ip_output+0x1c7/0x710 [ 261.269005] ? ip_mc_output+0x13f0/0x13f0 [ 261.273002] ? __local_bh_enable_ip+0xe9/0x1b0 [ 261.278152] ? ip_fragment.constprop.56+0x220/0x220 [ 261.282996] ? nf_hook_slow+0xb1/0x160 [ 261.287007] raw_sendmsg+0x21f9/0x4420 [ 261.291008] ? dst_output+0x180/0x180 [ 261.297003] ? sched_clock_cpu+0x126/0x170 [ 261.301003] ? find_held_lock+0x39/0x1c0 [ 261.306155] ? stop_critical_timings+0x420/0x420 [ 261.311004] ? check_flags.part.36+0x450/0x450 [ 261.315005] ? _raw_spin_unlock_irq+0x29/0x40 [ 261.320995] ? _raw_spin_unlock_irq+0x29/0x40 [ 261.326142] ? cyc2ns_read_end+0x10/0x10 [ 261.330139] ? raw_bind+0x280/0x280 [ 261.334138] ? sched_clock_cpu+0x126/0x170 [ 261.338995] ? check_flags.part.36+0x450/0x450 [ 261.342991] ? __lock_acquire+0x4500/0x4500 [ 261.348994] ? inet_sendmsg+0x11c/0x500 [ 261.352989] ? dst_output+0x180/0x180 [ 261.357012] inet_sendmsg+0x11c/0x500 [ ... ] v2: - clear skb->sk at reassembly routine.(Eric Dumarzet) Fixes: fa0f527 ("ip: use rb trees for IP frag queue.") Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Taehee Yoo <ap420073@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

The following lockdep report can be triggered by writing to /sys/kernel/debug/sched_features: ====================================================== WARNING: possible circular locking dependency detected 4.18.0-rc6-00152-gcd3f77d74ac3-dirty #18 Not tainted ------------------------------------------------------ sh/3358 is trying to acquire lock: 000000004ad3989d (cpu_hotplug_lock.rw_sem){++++}, at: static_key_enable+0x14/0x30 but task is already holding lock: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&sb->s_type->i_mutex_key#3){+.+.}: lock_acquire+0xb8/0x148 down_write+0xac/0x140 start_creating+0x5c/0x168 debugfs_create_dir+0x18/0x220 opp_debug_register+0x8c/0x120 _add_opp_dev+0x104/0x1f8 dev_pm_opp_get_opp_table+0x174/0x340 _of_add_opp_table_v2+0x110/0x760 dev_pm_opp_of_add_table+0x5c/0x240 dev_pm_opp_of_cpumask_add_table+0x5c/0x100 cpufreq_init+0x160/0x430 cpufreq_online+0x1cc/0xe30 cpufreq_add_dev+0x78/0x198 subsys_interface_register+0x168/0x270 cpufreq_register_driver+0x1c8/0x278 dt_cpufreq_probe+0xdc/0x1b8 platform_drv_probe+0xb4/0x168 driver_probe_device+0x318/0x4b0 __device_attach_driver+0xfc/0x1f0 bus_for_each_drv+0xf8/0x180 __device_attach+0x164/0x200 device_initial_probe+0x10/0x18 bus_probe_device+0x110/0x178 device_add+0x6d8/0x908 platform_device_add+0x138/0x3d8 platform_device_register_full+0x1cc/0x1f8 cpufreq_dt_platdev_init+0x174/0x1bc do_one_initcall+0xb8/0x310 kernel_init_freeable+0x4b8/0x56c kernel_init+0x10/0x138 ret_from_fork+0x10/0x18 -> #2 (opp_table_lock){+.+.}: lock_acquire+0xb8/0x148 __mutex_lock+0x104/0xf50 mutex_lock_nested+0x1c/0x28 _of_add_opp_table_v2+0xb4/0x760 dev_pm_opp_of_add_table+0x5c/0x240 dev_pm_opp_of_cpumask_add_table+0x5c/0x100 cpufreq_init+0x160/0x430 cpufreq_online+0x1cc/0xe30 cpufreq_add_dev+0x78/0x198 subsys_interface_register+0x168/0x270 cpufreq_register_driver+0x1c8/0x278 dt_cpufreq_probe+0xdc/0x1b8 platform_drv_probe+0xb4/0x168 driver_probe_device+0x318/0x4b0 __device_attach_driver+0xfc/0x1f0 bus_for_each_drv+0xf8/0x180 __device_attach+0x164/0x200 device_initial_probe+0x10/0x18 bus_probe_device+0x110/0x178 device_add+0x6d8/0x908 platform_device_add+0x138/0x3d8 platform_device_register_full+0x1cc/0x1f8 cpufreq_dt_platdev_init+0x174/0x1bc do_one_initcall+0xb8/0x310 kernel_init_freeable+0x4b8/0x56c kernel_init+0x10/0x138 ret_from_fork+0x10/0x18 -> #1 (subsys mutex#6){+.+.}: lock_acquire+0xb8/0x148 __mutex_lock+0x104/0xf50 mutex_lock_nested+0x1c/0x28 subsys_interface_register+0xd8/0x270 cpufreq_register_driver+0x1c8/0x278 dt_cpufreq_probe+0xdc/0x1b8 platform_drv_probe+0xb4/0x168 driver_probe_device+0x318/0x4b0 __device_attach_driver+0xfc/0x1f0 bus_for_each_drv+0xf8/0x180 __device_attach+0x164/0x200 device_initial_probe+0x10/0x18 bus_probe_device+0x110/0x178 device_add+0x6d8/0x908 platform_device_add+0x138/0x3d8 platform_device_register_full+0x1cc/0x1f8 cpufreq_dt_platdev_init+0x174/0x1bc do_one_initcall+0xb8/0x310 kernel_init_freeable+0x4b8/0x56c kernel_init+0x10/0x138 ret_from_fork+0x10/0x18 -> #0 (cpu_hotplug_lock.rw_sem){++++}: __lock_acquire+0x203c/0x21d0 lock_acquire+0xb8/0x148 cpus_read_lock+0x58/0x1c8 static_key_enable+0x14/0x30 sched_feat_write+0x314/0x428 full_proxy_write+0xa0/0x138 __vfs_write+0xd8/0x388 vfs_write+0xdc/0x318 ksys_write+0xb4/0x138 sys_write+0xc/0x18 __sys_trace_return+0x0/0x4 other info that might help us debug this: Chain exists of: cpu_hotplug_lock.rw_sem --> opp_table_lock --> &sb->s_type->i_mutex_key#3 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#3); lock(opp_table_lock); lock(&sb->s_type->i_mutex_key#3); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** 2 locks held by sh/3358: #0: 00000000a8c4b363 (sb_writers#10){.+.+}, at: vfs_write+0x238/0x318 #1: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428 stack backtrace: CPU: 5 PID: 3358 Comm: sh Not tainted 4.18.0-rc6-00152-gcd3f77d74ac3-dirty #18 Hardware name: Renesas H3ULCB Kingfisher board based on r8a7795 ES2.0+ (DT) Call trace: dump_backtrace+0x0/0x288 show_stack+0x14/0x20 dump_stack+0x13c/0x1ac print_circular_bug.isra.10+0x270/0x438 check_prev_add.constprop.16+0x4dc/0xb98 __lock_acquire+0x203c/0x21d0 lock_acquire+0xb8/0x148 cpus_read_lock+0x58/0x1c8 static_key_enable+0x14/0x30 sched_feat_write+0x314/0x428 full_proxy_write+0xa0/0x138 __vfs_write+0xd8/0x388 vfs_write+0xdc/0x318 ksys_write+0xb4/0x138 sys_write+0xc/0x18 __sys_trace_return+0x0/0x4 This is because when loading the cpufreq_dt module we first acquire cpu_hotplug_lock.rw_sem lock, then in cpufreq_init(), we are taking the &sb->s_type->i_mutex_key lock. But when writing to /sys/kernel/debug/sched_features, the cpu_hotplug_lock.rw_sem lock depends on the &sb->s_type->i_mutex_key lock. To fix this bug, reverse the lock acquisition order when writing to sched_features, this way cpu_hotplug_lock.rw_sem no longer depends on &sb->s_type->i_mutex_key. Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Jiada Wang <jiada_wang@mentor.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Eugeniu Rosca <erosca@de.adit-jv.com> Cc: George G. Davis <george_davis@mentor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180731121222.26195-1-jiada_wang@mentor.com Signed-off-by: Ingo Molnar <mingo@kernel.org>

In case local OOB data was generated and other device initiated pairing claiming that it has got OOB data, following crash occurred: [ 222.847853] general protection fault: 0000 [#1] SMP PTI [ 222.848025] CPU: 1 PID: 42 Comm: kworker/u5:0 Tainted: G C 4.18.0-custom #4 [ 222.848158] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 222.848307] Workqueue: hci0 hci_rx_work [bluetooth] [ 222.848416] RIP: 0010:compute_ecdh_secret+0x5a/0x270 [bluetooth] [ 222.848540] Code: 0c af f5 48 8b 3d 46 de f0 f6 ba 40 00 00 00 be c0 00 60 00 e8 b7 7b c5 f5 48 85 c0 0f 84 ea 01 00 00 48 89 c3 e8 16 0c af f5 <49> 8b 47 38 be c0 00 60 00 8b 78 f8 48 83 c7 48 e8 51 84 c5 f5 48 [ 222.848914] RSP: 0018:ffffb1664087fbc0 EFLAGS: 00010293 [ 222.849021] RAX: ffff8a5750d7dc00 RBX: ffff8a5671096780 RCX: ffffffffc08bc32a [ 222.849111] RDX: 0000000000000000 RSI: 00000000006000c0 RDI: ffff8a5752003800 [ 222.849192] RBP: ffffb1664087fc60 R08: ffff8a57525280a0 R09: ffff8a5752003800 [ 222.849269] R10: ffffb1664087fc70 R11: 0000000000000093 R12: ffff8a5674396e00 [ 222.849350] R13: ffff8a574c2e79aa R14: ffff8a574c2e796a R15: 020e0e100d010101 [ 222.849429] FS: 0000000000000000(0000) GS:ffff8a5752500000(0000) knlGS:0000000000000000 [ 222.849518] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 222.849586] CR2: 000055856016a038 CR3: 0000000110d2c005 CR4: 00000000000606e0 [ 222.849671] Call Trace: [ 222.849745] ? sc_send_public_key+0x110/0x2a0 [bluetooth] [ 222.849825] ? sc_send_public_key+0x115/0x2a0 [bluetooth] [ 222.849925] smp_recv_cb+0x959/0x2490 [bluetooth] [ 222.850023] ? _cond_resched+0x19/0x40 [ 222.850105] ? mutex_lock+0x12/0x40 [ 222.850202] l2cap_recv_frame+0x109d/0x3420 [bluetooth] [ 222.850315] ? l2cap_recv_frame+0x109d/0x3420 [bluetooth] [ 222.850426] ? __switch_to_asm+0x34/0x70 [ 222.850515] ? __switch_to_asm+0x40/0x70 [ 222.850625] ? __switch_to_asm+0x34/0x70 [ 222.850724] ? __switch_to_asm+0x40/0x70 [ 222.850786] ? __switch_to_asm+0x34/0x70 [ 222.850846] ? __switch_to_asm+0x40/0x70 [ 222.852581] ? __switch_to_asm+0x34/0x70 [ 222.854976] ? __switch_to_asm+0x40/0x70 [ 222.857475] ? __switch_to_asm+0x40/0x70 [ 222.859775] ? __switch_to_asm+0x34/0x70 [ 222.861218] ? __switch_to_asm+0x40/0x70 [ 222.862327] ? __switch_to_asm+0x34/0x70 [ 222.863758] l2cap_recv_acldata+0x266/0x3c0 [bluetooth] [ 222.865122] hci_rx_work+0x1c9/0x430 [bluetooth] [ 222.867144] process_one_work+0x210/0x4c0 [ 222.868248] worker_thread+0x41/0x4d0 [ 222.869420] kthread+0x141/0x160 [ 222.870694] ? process_one_work+0x4c0/0x4c0 [ 222.871668] ? kthread_create_worker_on_cpu+0x90/0x90 [ 222.872896] ret_from_fork+0x35/0x40 [ 222.874132] Modules linked in: algif_hash algif_skcipher af_alg rfcomm bnep btusb btrtl btbcm btintel snd_intel8x0 cmac intel_rapl_perf vboxvideo(C) snd_ac97_codec bluetooth ac97_bus joydev ttm snd_pcm ecdh_generic drm_kms_helper snd_timer snd input_leds drm serio_raw fb_sys_fops soundcore syscopyarea sysfillrect sysimgblt mac_hid sch_fq_codel ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd glue_helper ahci psmouse libahci i2c_piix4 video e1000 pata_acpi [ 222.883153] fbcon_switch: detected unhandled fb_set_par error, error code -16 [ 222.886774] fbcon_switch: detected unhandled fb_set_par error, error code -16 [ 222.890503] ---[ end trace 6504aa7a777b5316 ]--- [ 222.890541] RIP: 0010:compute_ecdh_secret+0x5a/0x270 [bluetooth] [ 222.890551] Code: 0c af f5 48 8b 3d 46 de f0 f6 ba 40 00 00 00 be c0 00 60 00 e8 b7 7b c5 f5 48 85 c0 0f 84 ea 01 00 00 48 89 c3 e8 16 0c af f5 <49> 8b 47 38 be c0 00 60 00 8b 78 f8 48 83 c7 48 e8 51 84 c5 f5 48 [ 222.890555] RSP: 0018:ffffb1664087fbc0 EFLAGS: 00010293 [ 222.890561] RAX: ffff8a5750d7dc00 RBX: ffff8a5671096780 RCX: ffffffffc08bc32a [ 222.890565] RDX: 0000000000000000 RSI: 00000000006000c0 RDI: ffff8a5752003800 [ 222.890571] RBP: ffffb1664087fc60 R08: ffff8a57525280a0 R09: ffff8a5752003800 [ 222.890576] R10: ffffb1664087fc70 R11: 0000000000000093 R12: ffff8a5674396e00 [ 222.890581] R13: ffff8a574c2e79aa R14: ffff8a574c2e796a R15: 020e0e100d010101 [ 222.890586] FS: 0000000000000000(0000) GS:ffff8a5752500000(0000) knlGS:0000000000000000 [ 222.890591] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 222.890594] CR2: 000055856016a038 CR3: 0000000110d2c005 CR4: 00000000000606e0 This commit fixes a bug where invalid pointer to crypto tfm was used for SMP SC ECDH calculation when OOB was in use. Solution is to use same crypto tfm than when generating OOB material on generate_oob() function. This bug was introduced in commit c0153b0 ("Bluetooth: let the crypto subsystem generate the ecc privkey"). Bug was found by fuzzing kernel SMP implementation using Synopsys Defensics. Signed-off-by: Matias Karhumaa <matias.karhumaa@gmail.com> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Yonghong Song says: ==================== The support to dump program array and map_in_map maps for bpffs and bpftool is added. Patch #1 added bpffs support and Patch #2 added bpftool support. Please see individual patches for example output. ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>

There is RaceFuzzer report like below because we have no lock to close below the race between binder_mmap and binder_alloc_new_buf_locked. To close the race, let's use memory barrier so that if someone see alloc->vma is not NULL, alloc->vma_vm_mm should be never NULL. (I didn't add stable mark intentionallybecause standard android userspace libraries that interact with binder (libbinder & libhwbinder) prevent the mmap/ioctl race. - from Todd) " Thread interleaving: CPU0 (binder_alloc_mmap_handler) CPU1 (binder_alloc_new_buf_locked) ===== ===== // drivers/android/binder_alloc.c // #L718 (v4.18-rc3) alloc->vma = vma; // drivers/android/binder_alloc.c // #L346 (v4.18-rc3) if (alloc->vma == NULL) { ... // alloc->vma is not NULL at this point return ERR_PTR(-ESRCH); } ... // #L438 binder_update_page_range(alloc, 0, (void *)PAGE_ALIGN((uintptr_t)buffer->data), end_page_addr); // In binder_update_page_range() #L218 // But still alloc->vma_vm_mm is NULL here if (need_mm && mmget_not_zero(alloc->vma_vm_mm)) alloc->vma_vm_mm = vma->vm_mm; Crash Log: ================================================================== BUG: KASAN: null-ptr-deref in __atomic_add_unless include/asm-generic/atomic-instrumented.h:89 [inline] BUG: KASAN: null-ptr-deref in atomic_add_unless include/linux/atomic.h:533 [inline] BUG: KASAN: null-ptr-deref in mmget_not_zero include/linux/sched/mm.h:75 [inline] BUG: KASAN: null-ptr-deref in binder_update_page_range+0xece/0x18e0 drivers/android/binder_alloc.c:218 Write of size 4 at addr 0000000000000058 by task syz-executor0/11184 CPU: 1 PID: 11184 Comm: syz-executor0 Not tainted 4.18.0-rc3 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x16e/0x22c lib/dump_stack.c:113 kasan_report_error mm/kasan/report.c:352 [inline] kasan_report+0x163/0x380 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x140/0x1a0 mm/kasan/kasan.c:267 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278 __atomic_add_unless include/asm-generic/atomic-instrumented.h:89 [inline] atomic_add_unless include/linux/atomic.h:533 [inline] mmget_not_zero include/linux/sched/mm.h:75 [inline] binder_update_page_range+0xece/0x18e0 drivers/android/binder_alloc.c:218 binder_alloc_new_buf_locked drivers/android/binder_alloc.c:443 [inline] binder_alloc_new_buf+0x467/0xc30 drivers/android/binder_alloc.c:513 binder_transaction+0x125b/0x4fb0 drivers/android/binder.c:2957 binder_thread_write+0xc08/0x2770 drivers/android/binder.c:3528 binder_ioctl_write_read.isra.39+0x24f/0x8e0 drivers/android/binder.c:4456 binder_ioctl+0xa86/0xf34 drivers/android/binder.c:4596 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x154/0xd40 fs/ioctl.c:686 ksys_ioctl+0x94/0xb0 fs/ioctl.c:701 __do_sys_ioctl fs/ioctl.c:708 [inline] __se_sys_ioctl fs/ioctl.c:706 [inline] __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:706 do_syscall_64+0x167/0x4b0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe " Signed-off-by: Todd Kjos <tkjos@google.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Martijn Coenen <maco@android.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 12eeeb4. The patch doesn't fix accessing memory with null pointer in skl_interrupt(). There are two problems: 1) skl_init_chip() is called twice, before and after dma buffer is allocate. The first call sets bus->chip_init which prevents the second from initializing bus->corb.buf and rirb.buf from bus->rb.area. 2) snd_hdac_bus_init_chip() enables interrupt before snd_hdac_bus_init_cmd_io() initializing dma buffers. There is a small window which skl_interrupt() can be called if irq has been acquired. If so, it crashes when using null dma buffer pointers. Will fix the problems in the following patches. Also attaching the crash for future reference. [ 16.949148] general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI <snipped> [ 16.950903] Call Trace: [ 16.950906] <IRQ> [ 16.950918] skl_interrupt+0x19e/0x2d6 [snd_soc_skl] [ 16.950926] ? dma_supported+0xb5/0xb5 [snd_soc_skl] [ 16.950933] __handle_irq_event_percpu+0x27a/0x6c8 [ 16.950937] ? __irq_wake_thread+0x1d1/0x1d1 [ 16.950942] ? __do_softirq+0x57a/0x69e [ 16.950944] handle_irq_event_percpu+0x95/0x1ba [ 16.950948] ? _raw_spin_unlock+0x65/0xdc [ 16.950951] ? __handle_irq_event_percpu+0x6c8/0x6c8 [ 16.950953] ? _raw_spin_unlock+0x65/0xdc [ 16.950957] ? time_cpufreq_notifier+0x483/0x483 [ 16.950959] handle_irq_event+0x89/0x123 [ 16.950962] handle_fasteoi_irq+0x16f/0x425 [ 16.950965] handle_irq+0x1fe/0x28e [ 16.950969] do_IRQ+0x6e/0x12e [ 16.950972] common_interrupt+0x7a/0x7a [ 16.950974] </IRQ> <snipped> [ 16.951031] RIP: snd_hdac_bus_update_rirb+0x19b/0x4cf [snd_hda_core] RSP: ffff88015c807c08 [ 16.951036] ---[ end trace 58bf9ece1775bc92 ]--- Fixes: 2eeeb4f4733b ("ASoC: Intel: Skylake: Acquire irq after RIRB allocation") Signed-off-by: Yu Zhao <yuzhao@google.com> Signed-off-by: Mark Brown <broonie@kernel.org>

When netvsc device is removed it can call reschedule in RCU context. This happens because canceling the subchannel setup work could (in theory) cause a reschedule when manipulating the timer. To reproduce, run with lockdep enabled kernel and unbind a network device from hv_netvsc (via sysfs). [ 160.682011] WARNING: suspicious RCU usage [ 160.707466] 4.19.0-rc3-uio+ #2 Not tainted [ 160.709937] ----------------------------- [ 160.712352] ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section! [ 160.723691] [ 160.723691] other info that might help us debug this: [ 160.723691] [ 160.730955] [ 160.730955] rcu_scheduler_active = 2, debug_locks = 1 [ 160.762813] 5 locks held by rebind-eth.sh/1812: [ 160.766851] #0: 000000008befa37a (sb_writers#6){.+.+}, at: vfs_write+0x184/0x1b0 [ 160.773416] #1: 00000000b097f236 (&of->mutex){+.+.}, at: kernfs_fop_write+0xe2/0x1a0 [ 160.783766] #2: 0000000041ee6889 (kn->count#3){++++}, at: kernfs_fop_write+0xeb/0x1a0 [ 160.787465] #3: 0000000056d92a74 (&dev->mutex){....}, at: device_release_driver_internal+0x39/0x250 [ 160.816987] #4: 0000000030f6031e (rcu_read_lock){....}, at: netvsc_remove+0x1e/0x250 [hv_netvsc] [ 160.828629] [ 160.828629] stack backtrace: [ 160.831966] CPU: 1 PID: 1812 Comm: rebind-eth.sh Not tainted 4.19.0-rc3-uio+ #2 [ 160.832952] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012 [ 160.832952] Call Trace: [ 160.832952] dump_stack+0x85/0xcb [ 160.832952] ___might_sleep+0x1a3/0x240 [ 160.832952] __flush_work+0x57/0x2e0 [ 160.832952] ? __mutex_lock+0x83/0x990 [ 160.832952] ? __kernfs_remove+0x24f/0x2e0 [ 160.832952] ? __kernfs_remove+0x1b2/0x2e0 [ 160.832952] ? mark_held_locks+0x50/0x80 [ 160.832952] ? get_work_pool+0x90/0x90 [ 160.832952] __cancel_work_timer+0x13c/0x1e0 [ 160.832952] ? netvsc_remove+0x1e/0x250 [hv_netvsc] [ 160.832952] ? __lock_is_held+0x55/0x90 [ 160.832952] netvsc_remove+0x9a/0x250 [hv_netvsc] [ 160.832952] vmbus_remove+0x26/0x30 [ 160.832952] device_release_driver_internal+0x18a/0x250 [ 160.832952] unbind_store+0xb4/0x180 [ 160.832952] kernfs_fop_write+0x113/0x1a0 [ 160.832952] __vfs_write+0x36/0x1a0 [ 160.832952] ? rcu_read_lock_sched_held+0x6b/0x80 [ 160.832952] ? rcu_sync_lockdep_assert+0x2e/0x60 [ 160.832952] ? __sb_start_write+0x141/0x1a0 [ 160.832952] ? vfs_write+0x184/0x1b0 [ 160.832952] vfs_write+0xbe/0x1b0 [ 160.832952] ksys_write+0x55/0xc0 [ 160.832952] do_syscall_64+0x60/0x1b0 [ 160.832952] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 160.832952] RIP: 0033:0x7fe48f4c8154 Resolve this by getting RTNL earlier. This is safe because the subchannel work queue does trylock on RTNL and will detect the race. Fixes: 7b2ee50 ("hv_netvsc: common detach logic") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>

The command 'xl vcpu-set 0 0', issued in dom0, will crash dom0: BUG: unable to handle kernel NULL pointer dereference at 00000000000002d8 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 7 PID: 65 Comm: xenwatch Not tainted 4.19.0-rc2-1.ga9462db-default #1 openSUSE Tumbleweed (unreleased) Hardware name: Intel Corporation S5520UR/S5520UR, BIOS S5500.86B.01.00.0050.050620101605 05/06/2010 RIP: e030:device_offline+0x9/0xb0 Code: 77 24 00 e9 ce fe ff ff 48 8b 13 e9 68 ff ff ff 48 8b 13 e9 29 ff ff ff 48 8b 13 e9 ea fe ff ff 90 66 66 66 66 90 41 54 55 53 <f6> 87 d8 02 00 00 01 0f 85 88 00 00 00 48 c7 c2 20 09 60 81 31 f6 RSP: e02b:ffffc90040f27e80 EFLAGS: 00010203 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff8801f3800000 RSI: ffffc90040f27e70 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff820e47b3 R09: 0000000000000000 R10: 0000000000007ff0 R11: 0000000000000000 R12: ffffffff822e6d30 R13: dead000000000200 R14: dead000000000100 R15: ffffffff8158b4e0 FS: 00007ffa595158c0(0000) GS:ffff8801f39c0000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000002d8 CR3: 00000001d9602000 CR4: 0000000000002660 Call Trace: handle_vcpu_hotplug_event+0xb5/0xc0 xenwatch_thread+0x80/0x140 ? wait_woken+0x80/0x80 kthread+0x112/0x130 ? kthread_create_worker_on_cpu+0x40/0x40 ret_from_fork+0x3a/0x50 This happens because handle_vcpu_hotplug_event is called twice. In the first iteration cpu_present is still true, in the second iteration cpu_present is false which causes get_cpu_device to return NULL. In case of cpu#0, cpu_online is apparently always true. Fix this crash by checking if the cpu can be hotplugged, which is false for a cpu that was just removed. Also check if the cpu was actually offlined by device_remove, otherwise leave the cpu_present state as it is. Rearrange to code to do all work with device_hotplug_lock held. Signed-off-by: Olaf Hering <olaf@aepfle.de> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

…inux-nfs Pull NFS client bugfixes from Anna Schumaker: "These are a handful of fixes for problems that Trond found. Patch #1 and #3 have the same name, a second issue was found after applying the first patch. Stable bugfixes: - v4.17+: Fix tracepoint Oops in initiate_file_draining() - v4.11+: Fix an infinite loop on I/O Other fixes: - Return errors if a waiting layoutget is killed - Don't open code clearing of delegation state" * tag 'nfs-for-4.19-2' of git://git.linux-nfs.org/projects/anna/linux-nfs: NFS: Don't open code clearing of delegation state NFSv4.1 fix infinite loop on I/O. NFSv4: Fix a tracepoint Oops in initiate_file_draining() pNFS: Ensure we return the error if someone kills a waiting layoutget NFSv4: Fix a tracepoint Oops in initiate_file_draining()

Chen Yu reported a divide-by-zero error when accessing the 'size' resctrl file when a MBA resource is enabled. divide error: 0000 [#1] SMP PTI CPU: 93 PID: 1929 Comm: cat Not tainted 4.19.0-rc2-debug-rdt+ #25 RIP: 0010:rdtgroup_cbm_to_size+0x7e/0xa0 Call Trace: rdtgroup_size_show+0x11a/0x1d0 seq_read+0xd8/0x3b0 Quoting Chen Yu's report: This is because for MB resource, the r->cache.cbm_len is zero, thus calculating size in rdtgroup_cbm_to_size() will trigger the exception. Fix this issue in the 'size' file by getting correct memory bandwidth value which is in MBps when MBA software controller is enabled or in percentage when MBA software controller is disabled. Fixes: d9b48c8 ("x86/intel_rdt: Display resource groups' allocations in bytes") Reported-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Chen Yu <yu.c.chen@intel.com> Cc: "H Peter Anvin" <hpa@zytor.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: "Xiaochen Shen" <xiaochen.shen@intel.com> Link: https://lkml.kernel.org/r/20180904174614.26682-1-yu.c.chen@intel.com Link: https://lkml.kernel.org/r/1537048707-76280-3-git-send-email-fenghua.yu@intel.com

Running rcutorture scenario TREE05, the below warning is triggered. [ 32.604594] WARNING: suspicious RCU usage [ 32.605928] 6.11.0-rc5-00040-g4ba4f1afb6a9 #55238 Not tainted [ 32.607812] ----------------------------- [ 32.609140] kernel/events/core.c:13946 RCU-list traversed in non-reader section!! [ 32.611595] other info that might help us debug this: [ 32.614247] rcu_scheduler_active = 2, debug_locks = 1 [ 32.616392] 3 locks held by cpuhp/4/35: [ 32.617687] #0: ffffffffb666a650 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.620563] #1: ffffffffb666cd20 (cpuhp_state-down){+.+.}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.623412] #2: ffffffffb677c288 (pmus_lock){+.+.}-{3:3}, at: perf_event_exit_cpu_context+0x32/0x2f0 In perf_event_clear_cpumask(), uses list_for_each_entry_rcu() without an obvious RCU read-side critical section. Either pmus_srcu or pmus_lock is good enough to protect the pmus list. In the current context, pmus_lock is already held. The list_for_each_entry_rcu() is not required. Fixes: 4ba4f1a ("perf: Generic hotplug support for a PMU with a scope") Reported-by: Paul E. McKenney <paulmck@kernel.org> Closes: https://lore.kernel.org/lkml/2b66dff8-b827-494b-b151-1ad8d56f13e6@paulmck-laptop/ Tested-by: Paul E. McKenney <paulmck@kernel.org> Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202409131559.545634cc-oliver.sang@intel.com Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org>

Daniel Machon says: ==================== net: lan969x: add VCAP functionality == Description: This series is the third 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. 4) Add RGMII and FDMA functionality. == VCAP support: The Versatile Content-Aware Processor (VCAP) is a content-aware packet processor that allows wirespeed packet inspection for rich implementation of, for example, advanced VLAN and QoS classification and manipulations, IP source guarding, longest prefix matching for Layer-3 routing, and security features for wireline and wireless applications. This is all achieved by programming rules into the VCAP. When a VCAP is enabled, every frame passing through the switch is analyzed and multiple keys are created based on the contents of the frame. The frame is examined to determine the frame type (for example, IPv4 TCP frame), so that the frame information is extracted according to the frame type, port-specific configuration, and classification results from the basic classification. Keys are applied to the VCAP and when there is a match between a key and a rule in the VCAP, the rule is then applied to the frame from which the key was extracted. After this series is applied, the lan969x driver will support the same VCAP functionality as Sparx5. == Patch breakdown: Patch #1 exposes some VCAP symbols for lan969x. Patch #2 replaces VCAP uses of SPX5_PORTS with n_ports from the match data. Patch #3 adds new VCAP constants to match data Patch #4 removes the is_sparx5() check to now initialize the VCAP API on lan969x. Patch #5 adds the auto-generated VCAP data for lan969x. Patch #6 adds the VCAP configuration data for lan969x. Signed-off-by: Daniel Machon <daniel.machon@microchip.com> ==================== Link: https://patch.msgid.link/20241101-sparx5-lan969x-switch-driver-3-v1-0-3c76f22f4bfa@microchip.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Unloading the ice driver while switchdev port representors are added to a bridge can lead to kernel panic. Reproducer: modprobe ice devlink dev eswitch set $PF1_PCI mode switchdev ip link add $BR type bridge ip link set $BR up echo 2 > /sys/class/net/$PF1/device/sriov_numvfs sleep 2 ip link set $PF1 master $BR ip link set $VF1_PR master $BR ip link set $VF2_PR master $BR ip link set $PF1 up ip link set $VF1_PR up ip link set $VF2_PR up ip link set $VF1 up rmmod irdma ice When unloading the driver, ice_eswitch_detach() is eventually called as part of VF freeing. First, it removes a port representor from xarray, then unregister_netdev() is called (via repr->ops.rem()), finally representor is deallocated. The problem comes from the bridge doing its own deinit at the same time. unregister_netdev() triggers a notifier chain, resulting in ice_eswitch_br_port_deinit() being called. It should set repr->br_port = NULL, but this does not happen since repr has already been removed from xarray and is not found. Regardless, it finishes up deallocating br_port. At this point, repr is still not freed and an fdb event can happen, in which ice_eswitch_br_fdb_event_work() takes repr->br_port and tries to use it, which causes a panic (use after free). Note that this only happens with 2 or more port representors added to the bridge, since with only one representor port, the bridge deinit is slightly different (ice_eswitch_br_port_deinit() is called via ice_eswitch_br_ports_flush(), not ice_eswitch_br_port_unlink()). Trace: Oops: general protection fault, probably for non-canonical address 0xf129010fd1a93284: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: maybe wild-memory-access in range [0x8948287e8d499420-0x8948287e8d499427] (...) Workqueue: ice_bridge_wq ice_eswitch_br_fdb_event_work [ice] RIP: 0010:__rht_bucket_nested+0xb4/0x180 (...) Call Trace: (...) ice_eswitch_br_fdb_find+0x3fa/0x550 [ice] ? __pfx_ice_eswitch_br_fdb_find+0x10/0x10 [ice] ice_eswitch_br_fdb_event_work+0x2de/0x1e60 [ice] ? __schedule+0xf60/0x5210 ? mutex_lock+0x91/0xe0 ? __pfx_ice_eswitch_br_fdb_event_work+0x10/0x10 [ice] ? ice_eswitch_br_update_work+0x1f4/0x310 [ice] (...) A workaround is available: brctl setageing $BR 0, which stops the bridge from adding fdb entries altogether. Change the order of operations in ice_eswitch_detach(): move the call to unregister_netdev() before removing repr from xarray. This way repr->br_port will be correctly set to NULL in ice_eswitch_br_port_deinit(), preventing a panic. Fixes: fff292b ("ice: add VF representors one by one") Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Marcin Szycik <marcin.szycik@linux.intel.com> Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Running rcutorture scenario TREE05, the below warning is triggered. [ 32.604594] WARNING: suspicious RCU usage [ 32.605928] 6.11.0-rc5-00040-g4ba4f1afb6a9 #55238 Not tainted [ 32.607812] ----------------------------- [ 32.609140] kernel/events/core.c:13946 RCU-list traversed in non-reader section!! [ 32.611595] other info that might help us debug this: [ 32.614247] rcu_scheduler_active = 2, debug_locks = 1 [ 32.616392] 3 locks held by cpuhp/4/35: [ 32.617687] #0: ffffffffb666a650 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.620563] #1: ffffffffb666cd20 (cpuhp_state-down){+.+.}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.623412] #2: ffffffffb677c288 (pmus_lock){+.+.}-{3:3}, at: perf_event_exit_cpu_context+0x32/0x2f0 In perf_event_clear_cpumask(), uses list_for_each_entry_rcu() without an obvious RCU read-side critical section. Either pmus_srcu or pmus_lock is good enough to protect the pmus list. In the current context, pmus_lock is already held. The list_for_each_entry_rcu() is not required. Fixes: 4ba4f1a ("perf: Generic hotplug support for a PMU with a scope") Reported-by: Paul E. McKenney <paulmck@kernel.org> Closes: https://lore.kernel.org/lkml/2b66dff8-b827-494b-b151-1ad8d56f13e6@paulmck-laptop/ Tested-by: Paul E. McKenney <paulmck@kernel.org> Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202409131559.545634cc-oliver.sang@intel.com Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org>

Currently, when configuring TMU (Time Management Unit) mode of a given router, we take into account only its own TMU requirements ignoring other routers in the domain. This is problematic if the router we are configuring has lower TMU requirements than what is already configured in the domain. In the scenario below, we have a host router with two USB4 ports: A and B. Port A connected to device router #1 (which supports CL states) and existing DisplayPort tunnel, thus, the TMU mode is HiFi uni-directional. 1. Initial topology [Host] A/ / [Device #1] / Monitor 2. Plug in device #2 (that supports CL states) to downstream port B of the host router [Host] A/ B\ / \ [Device #1] [Device #2] / Monitor The TMU mode on port B and port A will be configured to LowRes which is not what we want and will cause monitor to start flickering. To address this we first scan the domain and search for any router configured to HiFi uni-directional mode, and if found, configure TMU mode of the given router to HiFi uni-directional as well. Cc: stable@vger.kernel.org Signed-off-by: Gil Fine <gil.fine@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

The purpose of btrfs_bbio_propagate_error() shall be propagating an error of split bio to its original btrfs_bio, and tell the error to the upper layer. However, it's not working well on some cases. * Case 1. Immediate (or quick) end_bio with an error When btrfs sends btrfs_bio to mirrored devices, btrfs calls btrfs_bio_end_io() when all the mirroring bios are completed. If that btrfs_bio was split, it is from btrfs_clone_bioset and its end_io function is btrfs_orig_write_end_io. For this case, btrfs_bbio_propagate_error() accesses the orig_bbio's bio context to increase the error count. That works well in most cases. However, if the end_io is called enough fast, orig_bbio's (remaining part after split) bio context may not be properly set at that time. Since the bio context is set when the orig_bbio (the last btrfs_bio) is sent to devices, that might be too late for earlier split btrfs_bio's completion. That will result in NULL pointer dereference. That bug is easily reproducible by running btrfs/146 on zoned devices [1] and it shows the following trace. [1] You need raid-stripe-tree feature as it create "-d raid0 -m raid1" FS. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 Not tainted 6.11.0-rc7-BTRFS-ZNS+ #474 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: writeback wb_workfn (flush-btrfs-5) RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs] BTRFS error (device dm-0): bdev /dev/mapper/error-test errs: wr 2, rd 0, flush 0, corrupt 0, gen 0 RSP: 0018:ffffc9000006f248 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080 RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58 R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158 FS: 0000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __die_body.cold+0x19/0x26 ? page_fault_oops+0x13e/0x2b0 ? _printk+0x58/0x73 ? do_user_addr_fault+0x5f/0x750 ? exc_page_fault+0x76/0x240 ? asm_exc_page_fault+0x22/0x30 ? btrfs_bio_end_io+0xae/0xc0 [btrfs] ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs] btrfs_orig_write_end_io+0x51/0x90 [btrfs] dm_submit_bio+0x5c2/0xa50 [dm_mod] ? find_held_lock+0x2b/0x80 ? blk_try_enter_queue+0x90/0x1e0 __submit_bio+0xe0/0x130 ? ktime_get+0x10a/0x160 ? lockdep_hardirqs_on+0x74/0x100 submit_bio_noacct_nocheck+0x199/0x410 btrfs_submit_bio+0x7d/0x150 [btrfs] btrfs_submit_chunk+0x1a1/0x6d0 [btrfs] ? lockdep_hardirqs_on+0x74/0x100 ? __folio_start_writeback+0x10/0x2c0 btrfs_submit_bbio+0x1c/0x40 [btrfs] submit_one_bio+0x44/0x60 [btrfs] submit_extent_folio+0x13f/0x330 [btrfs] ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs] extent_writepage_io+0x18b/0x360 [btrfs] extent_write_locked_range+0x17c/0x340 [btrfs] ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs] run_delalloc_cow+0x71/0xd0 [btrfs] btrfs_run_delalloc_range+0x176/0x500 [btrfs] ? find_lock_delalloc_range+0x119/0x260 [btrfs] writepage_delalloc+0x2ab/0x480 [btrfs] extent_write_cache_pages+0x236/0x7d0 [btrfs] btrfs_writepages+0x72/0x130 [btrfs] do_writepages+0xd4/0x240 ? find_held_lock+0x2b/0x80 ? wbc_attach_and_unlock_inode+0x12c/0x290 ? wbc_attach_and_unlock_inode+0x12c/0x290 __writeback_single_inode+0x5c/0x4c0 ? do_raw_spin_unlock+0x49/0xb0 writeback_sb_inodes+0x22c/0x560 __writeback_inodes_wb+0x4c/0xe0 wb_writeback+0x1d6/0x3f0 wb_workfn+0x334/0x520 process_one_work+0x1ee/0x570 ? lock_is_held_type+0xc6/0x130 worker_thread+0x1d1/0x3b0 ? __pfx_worker_thread+0x10/0x10 kthread+0xee/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Modules linked in: dm_mod btrfs blake2b_generic xor raid6_pq rapl CR2: 0000000000000020 * Case 2. Earlier completion of orig_bbio for mirrored btrfs_bios btrfs_bbio_propagate_error() assumes the end_io function for orig_bbio is called last among split bios. In that case, btrfs_orig_write_end_io() sets the bio->bi_status to BLK_STS_IOERR by seeing the bioc->error [2]. Otherwise, the increased orig_bio's bioc->error is not checked by anyone and return BLK_STS_OK to the upper layer. [2] Actually, this is not true. Because we only increases orig_bioc->errors by max_errors, the condition "atomic_read(&bioc->error) > bioc->max_errors" is still not met if only one split btrfs_bio fails. * Case 3. Later completion of orig_bbio for un-mirrored btrfs_bios In contrast to the above case, btrfs_bbio_propagate_error() is not working well if un-mirrored orig_bbio is completed last. It sets orig_bbio->bio.bi_status to the btrfs_bio's error. But, that is easily over-written by orig_bbio's completion status. If the status is BLK_STS_OK, the upper layer would not know the failure. * Solution Considering the above cases, we can only save the error status in the orig_bbio (remaining part after split) itself as it is always available. Also, the saved error status should be propagated when all the split btrfs_bios are finished (i.e, bbio->pending_ios == 0). This commit introduces "status" to btrfs_bbio and saves the first error of split bios to original btrfs_bio's "status" variable. When all the split bios are finished, the saved status is loaded into original btrfs_bio's status. With this commit, btrfs/146 on zoned devices does not hit the NULL pointer dereference anymore. Fixes: 852eee6 ("btrfs: allow btrfs_submit_bio to split bios") CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>

Running rcutorture scenario TREE05, the below warning is triggered. [ 32.604594] WARNING: suspicious RCU usage [ 32.605928] 6.11.0-rc5-00040-g4ba4f1afb6a9 #55238 Not tainted [ 32.607812] ----------------------------- [ 32.609140] kernel/events/core.c:13946 RCU-list traversed in non-reader section!! [ 32.611595] other info that might help us debug this: [ 32.614247] rcu_scheduler_active = 2, debug_locks = 1 [ 32.616392] 3 locks held by cpuhp/4/35: [ 32.617687] #0: ffffffffb666a650 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.620563] #1: ffffffffb666cd20 (cpuhp_state-down){+.+.}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.623412] #2: ffffffffb677c288 (pmus_lock){+.+.}-{3:3}, at: perf_event_exit_cpu_context+0x32/0x2f0 In perf_event_clear_cpumask(), uses list_for_each_entry_rcu() without an obvious RCU read-side critical section. Either pmus_srcu or pmus_lock is good enough to protect the pmus list. In the current context, pmus_lock is already held. The list_for_each_entry_rcu() is not required. Fixes: 4ba4f1a ("perf: Generic hotplug support for a PMU with a scope") Closes: https://lore.kernel.org/lkml/2b66dff8-b827-494b-b151-1ad8d56f13e6@paulmck-laptop/ Closes: https://lore.kernel.org/oe-lkp/202409131559.545634cc-oliver.sang@intel.com Reported-by: "Paul E. McKenney" <paulmck@kernel.org> Reported-by: kernel test robot <oliver.sang@intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: "Paul E. McKenney" <paulmck@kernel.org> Link: https://lore.kernel.org/r/20240913162340.2142976-1-kan.liang@linux.intel.com

… non-PCI device The function cxl_endpoint_gather_bandwidth() invokes pci_bus_read/write_XXX(), however, not all CXL devices are presently implemented via PCI. It is recognized that the cxl_test has realized a CXL device using a platform device. Calling pci_bus_read/write_XXX() in cxl_test will cause kernel panic: platform cxl_host_bridge.3: host supports CXL (restricted) Oops: general protection fault, probably for non-canonical address 0x3ef17856fcae4fbd: 0000 [#1] PREEMPT SMP PTI Call Trace: <TASK> ? __die_body.cold+0x19/0x27 ? die_addr+0x38/0x60 ? exc_general_protection+0x1f5/0x4b0 ? asm_exc_general_protection+0x22/0x30 ? pci_bus_read_config_word+0x1c/0x60 pcie_capability_read_word+0x93/0xb0 pcie_link_speed_mbps+0x18/0x50 cxl_pci_get_bandwidth+0x18/0x60 [cxl_core] cxl_endpoint_gather_bandwidth.constprop.0+0xf4/0x230 [cxl_core] ? xas_store+0x54/0x660 ? preempt_count_add+0x69/0xa0 ? _raw_spin_lock+0x13/0x40 ? __kmalloc_cache_noprof+0xe7/0x270 cxl_region_shared_upstream_bandwidth_update+0x9c/0x790 [cxl_core] cxl_region_attach+0x520/0x7e0 [cxl_core] store_targetN+0xf2/0x120 [cxl_core] kernfs_fop_write_iter+0x13a/0x1f0 vfs_write+0x23b/0x410 ksys_write+0x53/0xd0 do_syscall_64+0x62/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e And Ying also reported a KASAN error with similar calltrace. Reported-by: Huang, Ying <ying.huang@intel.com> Closes: http://lore.kernel.org/87y12w9vp5.fsf@yhuang6-desk2.ccr.corp.intel.com Fixes: a5ab0de ("cxl: Calculate region bandwidth of targets with shared upstream link") Signed-off-by: Li Zhijian <lizhijian@fujitsu.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Huang, Ying <ying.huang@intel.com> Link: https://patch.msgid.link/20241022030054.258942-1-lizhijian@fujitsu.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>

In support of investigating an initialization failure report [1], cxl_test was updated to register mock memory-devices after the mock root-port/bus device had been registered. That led to cxl_test crashing with a use-after-free bug with the following signature: cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1 cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1 cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0 1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1 [..] cxld_unregister: cxl decoder14.0: cxl_region_decode_reset: cxl_region region3: mock_decoder_reset: cxl_port port3: decoder3.0 reset 2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1 cxl_endpoint_decoder_release: cxl decoder14.0: [..] cxld_unregister: cxl decoder7.0: 3) cxl_region_decode_reset: cxl_region region3: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI [..] RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core] [..] Call Trace: <TASK> cxl_region_decode_reset+0x69/0x190 [cxl_core] cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x5d/0x60 [cxl_core] At 1) a region has been established with 2 endpoint decoders (7.0 and 14.0). Those endpoints share a common switch-decoder in the topology (3.0). At teardown, 2), decoder14.0 is the first to be removed and hits the "out of order reset case" in the switch decoder. The effect though is that region3 cleanup is aborted leaving it in-tact and referencing decoder14.0. At 3) the second attempt to teardown region3 trips over the stale decoder14.0 object which has long since been deleted. The fix here is to recognize that the CXL specification places no mandate on in-order shutdown of switch-decoders, the driver enforces in-order allocation, and hardware enforces in-order commit. So, rather than fail and leave objects dangling, always remove them. In support of making cxl_region_decode_reset() always succeed, cxl_region_invalidate_memregion() failures are turned into warnings. Crashing the kernel is ok there since system integrity is at risk if caches cannot be managed around physical address mutation events like CXL region destruction. A new device_for_each_child_reverse_from() is added to cleanup port->commit_end after all dependent decoders have been disabled. In other words if decoders are allocated 0->1->2 and disabled 1->2->0 then port->commit_end only decrements from 2 after 2 has been disabled, and it decrements all the way to zero since 1 was disabled previously. Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Cc: stable@vger.kernel.org Fixes: 176baef ("cxl/hdm: Commit decoder state to hardware") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Zijun Hu <quic_zijuhu@quicinc.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>

The following BUG was triggered: ============================= [ BUG: Invalid wait context ] 6.12.0-rc2-XXX #406 Not tainted ----------------------------- kworker/1:1/62 is trying to lock: ffffff8801593030 (&cpc_ptr->rmw_lock){+.+.}-{3:3}, at: cpc_write+0xcc/0x370 other info that might help us debug this: context-{5:5} 2 locks held by kworker/1:1/62: #0: ffffff897ef5ec98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x50 #1: ffffff880154e238 (&sg_policy->update_lock){....}-{2:2}, at: sugov_update_shared+0x3c/0x280 stack backtrace: CPU: 1 UID: 0 PID: 62 Comm: kworker/1:1 Not tainted 6.12.0-rc2-g9654bd3e8806 #406 Workqueue: 0x0 (events) Call trace: dump_backtrace+0xa4/0x130 show_stack+0x20/0x38 dump_stack_lvl+0x90/0xd0 dump_stack+0x18/0x28 __lock_acquire+0x480/0x1ad8 lock_acquire+0x114/0x310 _raw_spin_lock+0x50/0x70 cpc_write+0xcc/0x370 cppc_set_perf+0xa0/0x3a8 cppc_cpufreq_fast_switch+0x40/0xc0 cpufreq_driver_fast_switch+0x4c/0x218 sugov_update_shared+0x234/0x280 update_load_avg+0x6ec/0x7b8 dequeue_entities+0x108/0x830 dequeue_task_fair+0x58/0x408 __schedule+0x4f0/0x1070 schedule+0x54/0x130 worker_thread+0xc0/0x2e8 kthread+0x130/0x148 ret_from_fork+0x10/0x20 sugov_update_shared() locks a raw_spinlock while cpc_write() locks a spinlock. To have a correct wait-type order, update rmw_lock to a raw spinlock and ensure that interrupts will be disabled on the CPU holding it. Fixes: 60949b7 ("ACPI: CPPC: Fix MASK_VAL() usage") Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Link: https://patch.msgid.link/20241028125657.1271512-1-pierre.gondois@arm.com [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

When we compile and load lib/slub_kunit.c,it will cause a panic. The root cause is that __kmalloc_cache_noprof was directly called instead of kmem_cache_alloc,which resulted in no alloc_tag being allocated.This caused current->alloc_tag to be null,leading to a null pointer dereference in alloc_tag_ref_set. Despite the fact that my colleague Pei Xiao will later fix the code in slub_kunit.c,we still need fix null pointer check logic for ref and tag to avoid panic caused by a null pointer dereference. Here is the log for the panic: [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020 [ 74.780130][ T2158] Mem abort info: [ 74.780406][ T2158] ESR = 0x0000000096000004 [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits [ 74.781225][ T2158] SET = 0, FnV = 0 [ 74.781529][ T2158] EA = 0, S1PTW = 0 [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault [ 74.782288][ T2158] Data abort info: [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000 [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000 [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4 [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2 [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.794095][ T2158] sp : ffff800084d33cd0 [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000 [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314 [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088 [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00 [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537 [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0 [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001 [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000 [ 74.801656][ T2158] Call trace: [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit] [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit] [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit] [ 74.804768][ T2158] kthread+0x10c/0x118 [ 74.805141][ T2158] ret_from_fork+0x10/0x20 [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3) [ 74.806176][ T2158] SMP: stopping secondary CPUs [ 74.808130][ T2158] Starting crashdump kernel... Link: https://lkml.kernel.org/r/20241020070819.307944-1-hao.ge@linux.dev Fixes: e0a955b ("mm/codetag: add pgalloc_tag_copy()") Signed-off-by: Hao Ge <gehao@kylinos.cn> Acked-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Yu Zhao <yuzhao@google.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Eric reported a division by zero splat in the MPTCP protocol: Oops: divide error: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 6094 Comm: syz-executor317 Not tainted 6.12.0-rc5-syzkaller-00291-g05b92660cdfe #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__tcp_select_window+0x5b4/0x1310 net/ipv4/tcp_output.c:3163 Code: f6 44 01 e3 89 df e8 9b 75 09 f8 44 39 f3 0f 8d 11 ff ff ff e8 0d 74 09 f8 45 89 f4 e9 04 ff ff ff e8 00 74 09 f8 44 89 f0 99 <f7> 7c 24 14 41 29 d6 45 89 f4 e9 ec fe ff ff e8 e8 73 09 f8 48 89 RSP: 0018:ffffc900041f7930 EFLAGS: 00010293 RAX: 0000000000017e67 RBX: 0000000000017e67 RCX: ffffffff8983314b RDX: 0000000000000000 RSI: ffffffff898331b0 RDI: 0000000000000004 RBP: 00000000005d6000 R08: 0000000000000004 R09: 0000000000017e67 R10: 0000000000003e80 R11: 0000000000000000 R12: 0000000000003e80 R13: ffff888031d9b440 R14: 0000000000017e67 R15: 00000000002eb000 FS: 00007feb5d7f16c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb5d8adbb8 CR3: 0000000074e4c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __tcp_cleanup_rbuf+0x3e7/0x4b0 net/ipv4/tcp.c:1493 mptcp_rcv_space_adjust net/mptcp/protocol.c:2085 [inline] mptcp_recvmsg+0x2156/0x2600 net/mptcp/protocol.c:2289 inet_recvmsg+0x469/0x6a0 net/ipv4/af_inet.c:885 sock_recvmsg_nosec net/socket.c:1051 [inline] sock_recvmsg+0x1b2/0x250 net/socket.c:1073 __sys_recvfrom+0x1a5/0x2e0 net/socket.c:2265 __do_sys_recvfrom net/socket.c:2283 [inline] __se_sys_recvfrom net/socket.c:2279 [inline] __x64_sys_recvfrom+0xe0/0x1c0 net/socket.c:2279 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7feb5d857559 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007feb5d7f1208 EFLAGS: 00000246 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00007feb5d8e1318 RCX: 00007feb5d857559 RDX: 000000800000000e RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007feb5d8e1310 R08: 0000000000000000 R09: ffffffff81000000 R10: 0000000000000100 R11: 0000000000000246 R12: 00007feb5d8e131c R13: 00007feb5d8ae074 R14: 000000800000000e R15: 00000000fffffdef and provided a nice reproducer. The root cause is the current bad handling of racing disconnect. After the blamed commit below, sk_wait_data() can return (with error) with the underlying socket disconnected and a zero rcv_mss. Catch the error and return without performing any additional operations on the current socket. Reported-by: Eric Dumazet <edumazet@google.com> Fixes: 419ce13 ("tcp: allow again tcp_disconnect() when threads are waiting") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Message-Id: <8c82ecf71662ecbc47bf390f9905de70884c9f2d.1731060874.git.pabeni@redhat.com>

Eric reported a division by zero splat in the MPTCP protocol: Oops: divide error: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 6094 Comm: syz-executor317 Not tainted 6.12.0-rc5-syzkaller-00291-g05b92660cdfe #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__tcp_select_window+0x5b4/0x1310 net/ipv4/tcp_output.c:3163 Code: f6 44 01 e3 89 df e8 9b 75 09 f8 44 39 f3 0f 8d 11 ff ff ff e8 0d 74 09 f8 45 89 f4 e9 04 ff ff ff e8 00 74 09 f8 44 89 f0 99 <f7> 7c 24 14 41 29 d6 45 89 f4 e9 ec fe ff ff e8 e8 73 09 f8 48 89 RSP: 0018:ffffc900041f7930 EFLAGS: 00010293 RAX: 0000000000017e67 RBX: 0000000000017e67 RCX: ffffffff8983314b RDX: 0000000000000000 RSI: ffffffff898331b0 RDI: 0000000000000004 RBP: 00000000005d6000 R08: 0000000000000004 R09: 0000000000017e67 R10: 0000000000003e80 R11: 0000000000000000 R12: 0000000000003e80 R13: ffff888031d9b440 R14: 0000000000017e67 R15: 00000000002eb000 FS: 00007feb5d7f16c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb5d8adbb8 CR3: 0000000074e4c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __tcp_cleanup_rbuf+0x3e7/0x4b0 net/ipv4/tcp.c:1493 mptcp_rcv_space_adjust net/mptcp/protocol.c:2085 [inline] mptcp_recvmsg+0x2156/0x2600 net/mptcp/protocol.c:2289 inet_recvmsg+0x469/0x6a0 net/ipv4/af_inet.c:885 sock_recvmsg_nosec net/socket.c:1051 [inline] sock_recvmsg+0x1b2/0x250 net/socket.c:1073 __sys_recvfrom+0x1a5/0x2e0 net/socket.c:2265 __do_sys_recvfrom net/socket.c:2283 [inline] __se_sys_recvfrom net/socket.c:2279 [inline] __x64_sys_recvfrom+0xe0/0x1c0 net/socket.c:2279 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7feb5d857559 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007feb5d7f1208 EFLAGS: 00000246 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00007feb5d8e1318 RCX: 00007feb5d857559 RDX: 000000800000000e RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007feb5d8e1310 R08: 0000000000000000 R09: ffffffff81000000 R10: 0000000000000100 R11: 0000000000000246 R12: 00007feb5d8e131c R13: 00007feb5d8ae074 R14: 000000800000000e R15: 00000000fffffdef and provided a nice reproducer. The root cause is the current bad handling of racing disconnect. After the blamed commit below, sk_wait_data() can return (with error) with the underlying socket disconnected and a zero rcv_mss. Catch the error and return without performing any additional operations on the current socket. Reported-by: Eric Dumazet <edumazet@google.com> Fixes: 419ce13 ("tcp: allow again tcp_disconnect() when threads are waiting") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>

mjmartineau closed this as completed Jun 21, 2018

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Data Acknowledgement if single node is used #1

Data Acknowledgement if single node is used #1

brodnev commented Jun 21, 2018

mjmartineau commented Jun 21, 2018

Data Acknowledgement if single node is used #1

Data Acknowledgement if single node is used #1

Comments

brodnev commented Jun 21, 2018

mjmartineau commented Jun 21, 2018