Skip to content
New issue

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

Sign up for GitHub

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

Already on GitHub? Sign in to your account

Jump to bottom

Sparse issues (make C=1) #46

Closed
matttbe opened this issue Jul 6, 2020 · 1 comment
Closed

Sparse issues (make C=1) #46

matttbe opened this issue Jul 6, 2020 · 1 comment

Comments

@matttbe
Copy link
Member

matttbe commented Jul 6, 2020

Hello,

When I use make C=1 net/mptcp/<file>.c, I guess two errors:

  • net/mptcp/mptcp_diag.c:
./include/net/sock.h:1612:31: warning: context imbalance in 'mptcp_diag_get_info' - unexpected unlock
  • net/mptcp/protocol.c:
net/mptcp/protocol.c:1531:24: warning: context imbalance in 'mptcp_sk_clone' - unexpected unlock

Is it really an issue? If not, is there a way to add something to avoid them?
@pabeni
Copy link

pabeni commented Jul 6, 2020

both this warning are due to core TCP APIs.

unlock_sock_fast() conditionally releases the socket lock, fooling sparse

sk_clone_lock() conditionally acquires the socket lock, (if return value != 0), so we can't annotate the caller as 'release'. Again, sparse is fooled.

@pabeni pabeni closed this as completed Jul 6, 2020
jenkins-tessares pushed a commit that referenced this issue Aug 7, 2020
@guoren83
csky: Add support for function error injection
71e193d 
Inspired by the commit 42d038c ("arm64: Add support for function
error injection"), this patch supports function error injection for
csky.

This patch mainly support two functions: one is regs_set_return_value()
which is used to overwrite the return value; the another function is
override_function_with_return() which is to override the probed
function returning and jump to its caller.

Test log:

 cd /sys/kernel/debug/fail_function/
 echo sys_clone > inject
 echo 100 > probability
 echo 1 > interval
 ls /
[  108.644163] FAULT_INJECTION: forcing a failure.
[  108.644163] name fail_function, interval 1, probability 100, space 0, times 1
[  108.647799] CPU: 0 PID: 104 Comm: sh Not tainted 5.8.0-rc5+ #46
[  108.648384] Call Trace:
[  108.649339] [<8005eed4>] walk_stackframe+0x0/0xf0
[  108.649679] [<8005f16a>] show_stack+0x32/0x5c
[  108.649927] [<8040f9d2>] dump_stack+0x6e/0x9c
[  108.650271] [<80406f7e>] should_fail+0x15e/0x1ac
[  108.650720] [<80118ba8>] fei_kprobe_handler+0x28/0x5c
[  108.651519] [<80754110>] kprobe_breakpoint_handler+0x144/0x1cc
[  108.652289] [<8005d6da>] trap_c+0x8e/0x110
[  108.652816] [<8005ce8c>] csky_trap+0x5c/0x70
-sh: can't fork: Invalid argument

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
matttbe pushed a commit that referenced this issue Sep 23, 2020
@alexdeucher
drm/kfd: fix a system crash issue during GPU recovery
66a5710 
The crash log as the below:

[Thu Aug 20 23:18:14 2020] general protection fault: 0000 [#1] SMP NOPTI
[Thu Aug 20 23:18:14 2020] CPU: 152 PID: 1837 Comm: kworker/152:1 Tainted: G           OE     5.4.0-42-generic #46~18.04.1-Ubuntu
[Thu Aug 20 23:18:14 2020] Hardware name: GIGABYTE G482-Z53-YF/MZ52-G40-00, BIOS R12 05/13/2020
[Thu Aug 20 23:18:14 2020] Workqueue: events amdgpu_ras_do_recovery [amdgpu]
[Thu Aug 20 23:18:14 2020] RIP: 0010:evict_process_queues_cpsch+0xc9/0x130 [amdgpu]
[Thu Aug 20 23:18:14 2020] Code: 49 8d 4d 10 48 39 c8 75 21 eb 44 83 fa 03 74 36 80 78 72 00 74 0c 83 ab 68 01 00 00 01 41 c6 45 41 00 48 8b 00 48 39 c8 74 25 <80> 78 70 00 c6 40 6d 01 74 ee 8b 50 28 c6 40 70 00 83 ab 60 01 00
[Thu Aug 20 23:18:14 2020] RSP: 0018:ffffb29b52f6fc90 EFLAGS: 00010213
[Thu Aug 20 23:18:14 2020] RAX: 1c884edb0a118914 RBX: ffff8a0d45ff3c00 RCX: ffff8a2d83e41038
[Thu Aug 20 23:18:14 2020] RDX: 0000000000000000 RSI: 0000000000000082 RDI: ffff8a0e2e4178c0
[Thu Aug 20 23:18:14 2020] RBP: ffffb29b52f6fcb0 R08: 0000000000001b64 R09: 0000000000000004
[Thu Aug 20 23:18:14 2020] R10: ffffb29b52f6fb78 R11: 0000000000000001 R12: ffff8a0d45ff3d28
[Thu Aug 20 23:18:14 2020] R13: ffff8a2d83e41028 R14: 0000000000000000 R15: 0000000000000000
[Thu Aug 20 23:18:14 2020] FS:  0000000000000000(0000) GS:ffff8a0e2e400000(0000) knlGS:0000000000000000
[Thu Aug 20 23:18:14 2020] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[Thu Aug 20 23:18:14 2020] CR2: 000055c783c0e6a8 CR3: 00000034a1284000 CR4: 0000000000340ee0
[Thu Aug 20 23:18:14 2020] Call Trace:
[Thu Aug 20 23:18:14 2020]  kfd_process_evict_queues+0x43/0xd0 [amdgpu]
[Thu Aug 20 23:18:14 2020]  kfd_suspend_all_processes+0x60/0xf0 [amdgpu]
[Thu Aug 20 23:18:14 2020]  kgd2kfd_suspend.part.7+0x43/0x50 [amdgpu]
[Thu Aug 20 23:18:14 2020]  kgd2kfd_pre_reset+0x46/0x60 [amdgpu]
[Thu Aug 20 23:18:14 2020]  amdgpu_amdkfd_pre_reset+0x1a/0x20 [amdgpu]
[Thu Aug 20 23:18:14 2020]  amdgpu_device_gpu_recover+0x377/0xf90 [amdgpu]
[Thu Aug 20 23:18:14 2020]  ? amdgpu_ras_error_query+0x1b8/0x2a0 [amdgpu]
[Thu Aug 20 23:18:14 2020]  amdgpu_ras_do_recovery+0x159/0x190 [amdgpu]
[Thu Aug 20 23:18:14 2020]  process_one_work+0x20f/0x400
[Thu Aug 20 23:18:14 2020]  worker_thread+0x34/0x410

When GPU hang, user process will fail to create a compute queue whose
struct object will be freed later, but driver wrongly add this queue to
queue list of the proccess. And then kfd_process_evict_queues will
access a freed memory, which cause a system crash.

v2:
The failure to execute_queues should probably not be reported to
the caller of create_queue, because the queue was already created.
Therefore change to ignore the return value from execute_queues.

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Dennis Li <Dennis.Li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
matttbe pushed a commit that referenced this issue Nov 21, 2020
@shenki @kuba-moo
net: ftgmac100: Fix crash when removing driver
3d51794 
When removing the driver we would hit BUG_ON(!list_empty(&dev->ptype_specific))
in net/core/dev.c due to still having the NC-SI packet handler
registered.

 # echo 1e660000.ethernet > /sys/bus/platform/drivers/ftgmac100/unbind
  ------------[ cut here ]------------
  kernel BUG at net/core/dev.c:10254!
  Internal error: Oops - BUG: 0 [#1] SMP ARM
  CPU: 0 PID: 115 Comm: sh Not tainted 5.10.0-rc3-next-20201111-00007-g02e0365710c4 #46
  Hardware name: Generic DT based system
  PC is at netdev_run_todo+0x314/0x394
  LR is at cpumask_next+0x20/0x24
  pc : [<806f5830>]    lr : [<80863cb0>]    psr: 80000153
  sp : 855bbd58  ip : 00000001  fp : 855bbdac
  r10: 80c03d00  r9 : 80c06228  r8 : 81158c54
  r7 : 00000000  r6 : 80c05dec  r5 : 80c05d18  r4 : 813b9280
  r3 : 813b9054  r2 : 8122c470  r1 : 00000002  r0 : 00000002
  Flags: Nzcv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment none
  Control: 00c5387d  Table: 85514008  DAC: 00000051
  Process sh (pid: 115, stack limit = 0x7cb5703d)
 ...
  Backtrace:
  [<806f551c>] (netdev_run_todo) from [<80707eec>] (rtnl_unlock+0x18/0x1c)
   r10:00000051 r9:854ed710 r8:81158c54 r7:80c76bb0 r6:81158c10 r5:8115b410
   r4:813b9000
  [<80707ed4>] (rtnl_unlock) from [<806f5db8>] (unregister_netdev+0x2c/0x30)
  [<806f5d8c>] (unregister_netdev) from [<805a8180>] (ftgmac100_remove+0x20/0xa8)
   r5:8115b410 r4:813b9000
  [<805a8160>] (ftgmac100_remove) from [<805355e4>] (platform_drv_remove+0x34/0x4c)

Fixes: bd466c3 ("net/faraday: Support NCSI mode")
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20201117024448.1170761-1-joel@jms.id.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
jenkins-tessares pushed a commit that referenced this issue Apr 29, 2021
@anakryiko
selftests/bpf: Fix BPF_CORE_READ_BITFIELD() macro
0f20615 
Fix BPF_CORE_READ_BITFIELD() macro used for reading CO-RE-relocatable
bitfields. Missing breaks in a switch caused 8-byte reads always. This can
confuse libbpf because it does strict checks that memory load size corresponds
to the original size of the field, which in this case quite often would be
wrong.

After fixing that, we run into another problem, which quite subtle, so worth
documenting here. The issue is in Clang optimization and CO-RE relocation
interactions. Without that asm volatile construct (also known as
barrier_var()), Clang will re-order BYTE_OFFSET and BYTE_SIZE relocations and
will apply BYTE_OFFSET 4 times for each switch case arm. This will result in
the same error from libbpf about mismatch of memory load size and original
field size. I.e., if we were reading u32, we'd still have *(u8 *), *(u16 *),
*(u32 *), and *(u64 *) memory loads, three of which will fail. Using
barrier_var() forces Clang to apply BYTE_OFFSET relocation first (and once) to
calculate p, after which value of p is used without relocation in each of
switch case arms, doing appropiately-sized memory load.

Here's the list of relevant relocations and pieces of generated BPF code
before and after this patch for test_core_reloc_bitfields_direct selftests.

BEFORE
=====
 #45: core_reloc: insn #160 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32
 #46: core_reloc: insn #167 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 #47: core_reloc: insn #174 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 #48: core_reloc: insn #178 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 #49: core_reloc: insn #182 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32

     157:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     159:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     160:       b7 02 00 00 04 00 00 00 r2 = 4
; BYTE_SIZE relocation here                 ^^^
     161:       66 02 07 00 03 00 00 00 if w2 s> 3 goto +7 <LBB0_63>
     162:       16 02 0d 00 01 00 00 00 if w2 == 1 goto +13 <LBB0_65>
     163:       16 02 01 00 02 00 00 00 if w2 == 2 goto +1 <LBB0_66>
     164:       05 00 12 00 00 00 00 00 goto +18 <LBB0_69>

0000000000000528 <LBB0_66>:
     165:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     167:       69 11 08 00 00 00 00 00 r1 = *(u16 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     168:       05 00 0e 00 00 00 00 00 goto +14 <LBB0_69>

0000000000000548 <LBB0_63>:
     169:       16 02 0a 00 04 00 00 00 if w2 == 4 goto +10 <LBB0_67>
     170:       16 02 01 00 08 00 00 00 if w2 == 8 goto +1 <LBB0_68>
     171:       05 00 0b 00 00 00 00 00 goto +11 <LBB0_69>

0000000000000560 <LBB0_68>:
     172:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     174:       79 11 08 00 00 00 00 00 r1 = *(u64 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     175:       05 00 07 00 00 00 00 00 goto +7 <LBB0_69>

0000000000000580 <LBB0_65>:
     176:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     178:       71 11 08 00 00 00 00 00 r1 = *(u8 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     179:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

00000000000005a0 <LBB0_67>:
     180:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     182:       61 11 08 00 00 00 00 00 r1 = *(u32 *)(r1 + 8)
; BYTE_OFFSET relo here w/ RIGHT size        ^^^^^^^^^^^^^^^^

00000000000005b8 <LBB0_69>:
     183:       67 01 00 00 20 00 00 00 r1 <<= 32
     184:       b7 02 00 00 00 00 00 00 r2 = 0
     185:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     186:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     187:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000005e0 <LBB0_71>:
     188:       77 01 00 00 20 00 00 00 r1 >>= 32

AFTER
=====

 #30: core_reloc: insn #132 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 #31: core_reloc: insn #134 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32

     129:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     131:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     132:       b7 01 00 00 08 00 00 00 r1 = 8
; BYTE_OFFSET relo here                     ^^^
; no size check for non-memory dereferencing instructions
     133:       0f 12 00 00 00 00 00 00 r2 += r1
     134:       b7 03 00 00 04 00 00 00 r3 = 4
; BYTE_SIZE relocation here                 ^^^
     135:       66 03 05 00 03 00 00 00 if w3 s> 3 goto +5 <LBB0_63>
     136:       16 03 09 00 01 00 00 00 if w3 == 1 goto +9 <LBB0_65>
     137:       16 03 01 00 02 00 00 00 if w3 == 2 goto +1 <LBB0_66>
     138:       05 00 0a 00 00 00 00 00 goto +10 <LBB0_69>

0000000000000458 <LBB0_66>:
     139:       69 21 00 00 00 00 00 00 r1 = *(u16 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     140:       05 00 08 00 00 00 00 00 goto +8 <LBB0_69>

0000000000000468 <LBB0_63>:
     141:       16 03 06 00 04 00 00 00 if w3 == 4 goto +6 <LBB0_67>
     142:       16 03 01 00 08 00 00 00 if w3 == 8 goto +1 <LBB0_68>
     143:       05 00 05 00 00 00 00 00 goto +5 <LBB0_69>

0000000000000480 <LBB0_68>:
     144:       79 21 00 00 00 00 00 00 r1 = *(u64 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     145:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

0000000000000490 <LBB0_65>:
     146:       71 21 00 00 00 00 00 00 r1 = *(u8 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     147:       05 00 01 00 00 00 00 00 goto +1 <LBB0_69>

00000000000004a0 <LBB0_67>:
     148:       61 21 00 00 00 00 00 00 r1 = *(u32 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^

00000000000004a8 <LBB0_69>:
     149:       67 01 00 00 20 00 00 00 r1 <<= 32
     150:       b7 02 00 00 00 00 00 00 r2 = 0
     151:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     152:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     153:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000004d0 <LBB0_71>:
     154:       77 01 00 00 20 00 00 00 r1 >>= 323

Fixes: ee26dad ("libbpf: Add support for relocatable bitfields")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20210426192949.416837-4-andrii@kernel.org
dcaratti pushed a commit to dcaratti/mptcp_net-next that referenced this issue Sep 2, 2021
@smfrench
Merge pull request multipath-tcp#46 from namjaejeon/cifsd-for-next
2018da7 
cifsd-fixes
jenkins-tessares pushed a commit that referenced this issue Dec 31, 2021
@cminyard
ipmi: Fix UAF when uninstall ipmi_si and ipmi_msghandler module
ffb76a8 
Hi,

When testing install and uninstall of ipmi_si.ko and ipmi_msghandler.ko,
the system crashed.

The log as follows:
[  141.087026] BUG: unable to handle kernel paging request at ffffffffc09b3a5a
[  141.087241] PGD 8fe4c0d067 P4D 8fe4c0d067 PUD 8fe4c0f067 PMD 103ad89067 PTE 0
[  141.087464] Oops: 0010 [#1] SMP NOPTI
[  141.087580] CPU: 67 PID: 668 Comm: kworker/67:1 Kdump: loaded Not tainted 4.18.0.x86_64 #47
[  141.088009] Workqueue: events 0xffffffffc09b3a40
[  141.088009] RIP: 0010:0xffffffffc09b3a5a
[  141.088009] Code: Bad RIP value.
[  141.088009] RSP: 0018:ffffb9094e2c3e88 EFLAGS: 00010246
[  141.088009] RAX: 0000000000000000 RBX: ffff9abfdb1f04a0 RCX: 0000000000000000
[  141.088009] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  141.088009] RBP: 0000000000000000 R08: ffff9abfffee3cb8 R09: 00000000000002e1
[  141.088009] R10: ffffb9094cb73d90 R11: 00000000000f4240 R12: ffff9abfffee8700
[  141.088009] R13: 0000000000000000 R14: ffff9abfdb1f04a0 R15: ffff9abfdb1f04a8
[  141.088009] FS:  0000000000000000(0000) GS:ffff9abfffec0000(0000) knlGS:0000000000000000
[  141.088009] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  141.088009] CR2: ffffffffc09b3a30 CR3: 0000008fe4c0a001 CR4: 00000000007606e0
[  141.088009] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  141.088009] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  141.088009] PKRU: 55555554
[  141.088009] Call Trace:
[  141.088009]  ? process_one_work+0x195/0x390
[  141.088009]  ? worker_thread+0x30/0x390
[  141.088009]  ? process_one_work+0x390/0x390
[  141.088009]  ? kthread+0x10d/0x130
[  141.088009]  ? kthread_flush_work_fn+0x10/0x10
[  141.088009]  ? ret_from_fork+0x35/0x40] BUG: unable to handle kernel paging request at ffffffffc0b28a5a
[  200.223240] PGD 97fe00d067 P4D 97fe00d067 PUD 97fe00f067 PMD a580cbf067 PTE 0
[  200.223464] Oops: 0010 [#1] SMP NOPTI
[  200.223579] CPU: 63 PID: 664 Comm: kworker/63:1 Kdump: loaded Not tainted 4.18.0.x86_64 #46
[  200.224008] Workqueue: events 0xffffffffc0b28a40
[  200.224008] RIP: 0010:0xffffffffc0b28a5a
[  200.224008] Code: Bad RIP value.
[  200.224008] RSP: 0018:ffffbf3c8e2a3e88 EFLAGS: 00010246
[  200.224008] RAX: 0000000000000000 RBX: ffffa0799ad6bca0 RCX: 0000000000000000
[  200.224008] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246
[  200.224008] RBP: 0000000000000000 R08: ffff9fe43fde3cb8 R09: 00000000000000d5
[  200.224008] R10: ffffbf3c8cb53d90 R11: 00000000000f4240 R12: ffff9fe43fde8700
[  200.224008] R13: 0000000000000000 R14: ffffa0799ad6bca0 R15: ffffa0799ad6bca8
[  200.224008] FS:  0000000000000000(0000) GS:ffff9fe43fdc0000(0000) knlGS:0000000000000000
[  200.224008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  200.224008] CR2: ffffffffc0b28a30 CR3: 00000097fe00a002 CR4: 00000000007606e0
[  200.224008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  200.224008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  200.224008] PKRU: 55555554
[  200.224008] Call Trace:
[  200.224008]  ? process_one_work+0x195/0x390
[  200.224008]  ? worker_thread+0x30/0x390
[  200.224008]  ? process_one_work+0x390/0x390
[  200.224008]  ? kthread+0x10d/0x130
[  200.224008]  ? kthread_flush_work_fn+0x10/0x10
[  200.224008]  ? ret_from_fork+0x35/0x40
[  200.224008] kernel fault(0x1) notification starting on CPU 63
[  200.224008] kernel fault(0x1) notification finished on CPU 63
[  200.224008] CR2: ffffffffc0b28a5a
[  200.224008] ---[ end trace c82a412d93f57412 ]---

The reason is as follows:
T1: rmmod ipmi_si.
    ->ipmi_unregister_smi()
        -> ipmi_bmc_unregister()
            -> __ipmi_bmc_unregister()
                -> kref_put(&bmc->usecount, cleanup_bmc_device);
                    -> schedule_work(&bmc->remove_work);

T2: rmmod ipmi_msghandler.
    ipmi_msghander module uninstalled, and the module space
    will be freed.

T3: bmc->remove_work doing cleanup the bmc resource.
    -> cleanup_bmc_work()
        -> platform_device_unregister(&bmc->pdev);
            -> platform_device_del(pdev);
                -> device_del(&pdev->dev);
                    -> kobject_uevent(&dev->kobj, KOBJ_REMOVE);
                        -> kobject_uevent_env()
                            -> dev_uevent()
                                -> if (dev->type && dev->type->name)

   'dev->type'(bmc_device_type) pointer space has freed when uninstall
    ipmi_msghander module, 'dev->type->name' cause the system crash.

drivers/char/ipmi/ipmi_msghandler.c:
2820 static const struct device_type bmc_device_type = {
2821         .groups         = bmc_dev_attr_groups,
2822 };

Steps to reproduce:
Add a time delay in cleanup_bmc_work() function,
and uninstall ipmi_si and ipmi_msghandler module.

2910 static void cleanup_bmc_work(struct work_struct *work)
2911 {
2912         struct bmc_device *bmc = container_of(work, struct bmc_device,
2913                                               remove_work);
2914         int id = bmc->pdev.id; /* Unregister overwrites id */
2915
2916         msleep(3000);   <---
2917         platform_device_unregister(&bmc->pdev);
2918         ida_simple_remove(&ipmi_bmc_ida, id);
2919 }

Use 'remove_work_wq' instead of 'system_wq' to solve this issues.

Fixes: b2cfd8a ("ipmi: Rework device id and guid handling to catch changing BMCs")
Signed-off-by: Wu Bo <wubo40@huawei.com>
Message-Id: <1640070034-56671-1-git-send-email-wubo40@huawei.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
jenkins-tessares pushed a commit that referenced this issue Jun 18, 2022
@yonghong-song
selftests/bpf: Avoid skipping certain subtests
3831cd1 
Commit 704c91e ('selftests/bpf: Test "bpftool gen min_core_btf"')
added a test test_core_btfgen to test core relocation with btf
generated with 'bpftool gen min_core_btf'. Currently,
among 76 subtests, 25 are skipped.

  ...
  #46/69   core_reloc_btfgen/enumval:OK
  #46/70   core_reloc_btfgen/enumval___diff:OK
  #46/71   core_reloc_btfgen/enumval___val3_missing:OK
  #46/72   core_reloc_btfgen/enumval___err_missing:SKIP
  #46/73   core_reloc_btfgen/enum64val:OK
  #46/74   core_reloc_btfgen/enum64val___diff:OK
  #46/75   core_reloc_btfgen/enum64val___val3_missing:OK
  #46/76   core_reloc_btfgen/enum64val___err_missing:SKIP
  ...
  #46      core_reloc_btfgen:SKIP
  Summary: 1/51 PASSED, 25 SKIPPED, 0 FAILED

Alexei found that in the above core_reloc_btfgen/enum64val___err_missing
should not be skipped.

Currently, the core_reloc tests have some negative tests.
In Commit 704c91e, for core_reloc_btfgen, all negative tests
are skipped with the following condition
  if (!test_case->btf_src_file || test_case->fails) {
	test__skip();
	continue;
  }
This is too conservative. Negative tests do not fail
mkstemp() and run_btfgen() should not be skipped.
There are a few negative tests indeed failing run_btfgen()
and this patch added 'run_btfgen_fails' to mark these tests
so that they can be skipped for btfgen tests. With this,
we have
  ...
  #46/69   core_reloc_btfgen/enumval:OK
  #46/70   core_reloc_btfgen/enumval___diff:OK
  #46/71   core_reloc_btfgen/enumval___val3_missing:OK
  #46/72   core_reloc_btfgen/enumval___err_missing:OK
  #46/73   core_reloc_btfgen/enum64val:OK
  #46/74   core_reloc_btfgen/enum64val___diff:OK
  #46/75   core_reloc_btfgen/enum64val___val3_missing:OK
  #46/76   core_reloc_btfgen/enum64val___err_missing:OK
  ...
  Summary: 1/62 PASSED, 14 SKIPPED, 0 FAILED

Totally 14 subtests are skipped instead of 25.

Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220614055526.628299-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
jenkins-tessares pushed a commit that referenced this issue Oct 5, 2022
@paulmckrcu
sched/debug: Show the registers of 'current' in dump_cpu_task()
bc1cca9 
The dump_cpu_task() function does not print registers on architectures
that do not support NMIs.  However, registers can be useful for
debugging.  Fortunately, in the case where dump_cpu_task() is invoked
from an interrupt handler and is dumping the current CPU's stack, the
get_irq_regs() function can be used to get the registers.

Therefore, this commit makes dump_cpu_task() check to see if it is being
asked to dump the current CPU's stack from within an interrupt handler,
and, if so, it uses the get_irq_regs() function to obtain the registers.
On systems that do support NMIs, this commit has the further advantage
of avoiding a self-NMI in this case.

This is an example of rcu self-detected stall on arm64, which does not
support NMIs:
[   27.501721] rcu: INFO: rcu_preempt self-detected stall on CPU
[   27.502238] rcu:     0-....: (1250 ticks this GP) idle=4f7/1/0x4000000000000000 softirq=2594/2594 fqs=619
[   27.502632]  (t=1251 jiffies g=2989 q=29 ncpus=4)
[   27.503845] CPU: 0 PID: 306 Comm: test0 Not tainted 5.19.0-rc7-00009-g1c1a6c29ff99-dirty #46
[   27.504732] Hardware name: linux,dummy-virt (DT)
[   27.504947] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   27.504998] pc : arch_counter_read+0x18/0x24
[   27.505301] lr : arch_counter_read+0x18/0x24
[   27.505328] sp : ffff80000b29bdf0
[   27.505345] x29: ffff80000b29bdf0 x28: 0000000000000000 x27: 0000000000000000
[   27.505475] x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
[   27.505553] x23: 0000000000001f40 x22: ffff800009849c48 x21: 000000065f871ae0
[   27.505627] x20: 00000000000025ec x19: ffff80000a6eb300 x18: ffffffffffffffff
[   27.505654] x17: 0000000000000001 x16: 0000000000000000 x15: ffff80000a6d0296
[   27.505681] x14: ffffffffffffffff x13: ffff80000a29bc18 x12: 0000000000000426
[   27.505709] x11: 0000000000000162 x10: ffff80000a2f3c18 x9 : ffff80000a29bc18
[   27.505736] x8 : 00000000ffffefff x7 : ffff80000a2f3c18 x6 : 00000000759bd013
[   27.505761] x5 : 01ffffffffffffff x4 : 0002dc6c00000000 x3 : 0000000000000017
[   27.505787] x2 : 00000000000025ec x1 : ffff80000b29bdf0 x0 : 0000000075a30653
[   27.505937] Call trace:
[   27.506002]  arch_counter_read+0x18/0x24
[   27.506171]  ktime_get+0x48/0xa0
[   27.506207]  test_task+0x70/0xf0
[   27.506227]  kthread+0x10c/0x110
[   27.506243]  ret_from_fork+0x10/0x20

This is a marked improvement over the old output:
[   27.944550] rcu: INFO: rcu_preempt self-detected stall on CPU
[   27.944980] rcu:     0-....: (1249 ticks this GP) idle=cbb/1/0x4000000000000000 softirq=2610/2610 fqs=614
[   27.945407]  (t=1251 jiffies g=2681 q=28 ncpus=4)
[   27.945731] Task dump for CPU 0:
[   27.945844] task:test0           state:R  running task     stack:    0 pid:  306 ppid:     2 flags:0x0000000a
[   27.946073] Call trace:
[   27.946151]  dump_backtrace.part.0+0xc8/0xd4
[   27.946378]  show_stack+0x18/0x70
[   27.946405]  sched_show_task+0x150/0x180
[   27.946427]  dump_cpu_task+0x44/0x54
[   27.947193]  rcu_dump_cpu_stacks+0xec/0x130
[   27.947212]  rcu_sched_clock_irq+0xb18/0xef0
[   27.947231]  update_process_times+0x68/0xac
[   27.947248]  tick_sched_handle+0x34/0x60
[   27.947266]  tick_sched_timer+0x4c/0xa4
[   27.947281]  __hrtimer_run_queues+0x178/0x360
[   27.947295]  hrtimer_interrupt+0xe8/0x244
[   27.947309]  arch_timer_handler_virt+0x38/0x4c
[   27.947326]  handle_percpu_devid_irq+0x88/0x230
[   27.947342]  generic_handle_domain_irq+0x2c/0x44
[   27.947357]  gic_handle_irq+0x44/0xc4
[   27.947376]  call_on_irq_stack+0x2c/0x54
[   27.947415]  do_interrupt_handler+0x80/0x94
[   27.947431]  el1_interrupt+0x34/0x70
[   27.947447]  el1h_64_irq_handler+0x18/0x24
[   27.947462]  el1h_64_irq+0x64/0x68                       <--- the above backtrace is worthless
[   27.947474]  arch_counter_read+0x18/0x24
[   27.947487]  ktime_get+0x48/0xa0
[   27.947501]  test_task+0x70/0xf0
[   27.947520]  kthread+0x10c/0x110
[   27.947538]  ret_from_fork+0x10/0x20

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Valentin Schneider <vschneid@redhat.com>
jenkins-tessares pushed a commit that referenced this issue Nov 3, 2023
@alexdeucher
drm/amdgpu: Fix a null pointer access when the smc_rreg pointer is NULL
5104fdf 
In certain types of chips, such as VEGA20, reading the amdgpu_regs_smc file could result in an abnormal null pointer access when the smc_rreg pointer is NULL. Below are the steps to reproduce this issue and the corresponding exception log:

1. Navigate to the directory: /sys/kernel/debug/dri/0
2. Execute command: cat amdgpu_regs_smc
3. Exception Log::
[4005007.702554] BUG: kernel NULL pointer dereference, address: 0000000000000000
[4005007.702562] #PF: supervisor instruction fetch in kernel mode
[4005007.702567] #PF: error_code(0x0010) - not-present page
[4005007.702570] PGD 0 P4D 0
[4005007.702576] Oops: 0010 [#1] SMP NOPTI
[4005007.702581] CPU: 4 PID: 62563 Comm: cat Tainted: G           OE     5.15.0-43-generic #46-Ubunt       u
[4005007.702590] RIP: 0010:0x0
[4005007.702598] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.702600] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.702605] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.702609] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.702612] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.702615] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.702618] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.702622] FS:  00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.702626] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.702629] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0
[4005007.702633] Call Trace:
[4005007.702636]  <TASK>
[4005007.702640]  amdgpu_debugfs_regs_smc_read+0xb0/0x120 [amdgpu]
[4005007.703002]  full_proxy_read+0x5c/0x80
[4005007.703011]  vfs_read+0x9f/0x1a0
[4005007.703019]  ksys_read+0x67/0xe0
[4005007.703023]  __x64_sys_read+0x19/0x20
[4005007.703028]  do_syscall_64+0x5c/0xc0
[4005007.703034]  ? do_user_addr_fault+0x1e3/0x670
[4005007.703040]  ? exit_to_user_mode_prepare+0x37/0xb0
[4005007.703047]  ? irqentry_exit_to_user_mode+0x9/0x20
[4005007.703052]  ? irqentry_exit+0x19/0x30
[4005007.703057]  ? exc_page_fault+0x89/0x160
[4005007.703062]  ? asm_exc_page_fault+0x8/0x30
[4005007.703068]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[4005007.703075] RIP: 0033:0x7f5e07672992
[4005007.703079] Code: c0 e9 b2 fe ff ff 50 48 8d 3d fa b2 0c 00 e8 c5 1d 02 00 0f 1f 44 00 00 f3 0f        1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 e       c 28 48 89 54 24
[4005007.703083] RSP: 002b:00007ffe03097898 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[4005007.703088] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f5e07672992
[4005007.703091] RDX: 0000000000020000 RSI: 00007f5e06753000 RDI: 0000000000000003
[4005007.703094] RBP: 00007f5e06753000 R08: 00007f5e06752010 R09: 00007f5e06752010
[4005007.703096] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000022000
[4005007.703099] R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
[4005007.703105]  </TASK>
[4005007.703107] Modules linked in: nf_tables libcrc32c nfnetlink algif_hash af_alg binfmt_misc nls_       iso8859_1 ipmi_ssif ast intel_rapl_msr intel_rapl_common drm_vram_helper drm_ttm_helper amd64_edac t       tm edac_mce_amd kvm_amd ccp mac_hid k10temp kvm acpi_ipmi ipmi_si rapl sch_fq_codel ipmi_devintf ipm       i_msghandler msr parport_pc ppdev lp parport mtd pstore_blk efi_pstore ramoops pstore_zone reed_solo       mon ip_tables x_tables autofs4 ib_uverbs ib_core amdgpu(OE) amddrm_ttm_helper(OE) amdttm(OE) iommu_v       2 amd_sched(OE) amdkcl(OE) drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec rc_core        drm igb ahci xhci_pci libahci i2c_piix4 i2c_algo_bit xhci_pci_renesas dca
[4005007.703184] CR2: 0000000000000000
[4005007.703188] ---[ end trace ac65a538d240da39 ]---
[4005007.800865] RIP: 0010:0x0
[4005007.800871] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.800874] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.800878] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.800881] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.800883] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.800886] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.800888] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.800891] FS:  00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.800895] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.800898] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0

Signed-off-by: Qu Huang <qu.huang@linux.dev>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
cpaasch pushed a commit that referenced this issue Dec 4, 2023
@gregkh
drm/amdgpu: Fix a null pointer access when the smc_rreg pointer is NULL
6c1b3d8 
[ Upstream commit 5104fdf ]

In certain types of chips, such as VEGA20, reading the amdgpu_regs_smc file could result in an abnormal null pointer access when the smc_rreg pointer is NULL. Below are the steps to reproduce this issue and the corresponding exception log:

1. Navigate to the directory: /sys/kernel/debug/dri/0
2. Execute command: cat amdgpu_regs_smc
3. Exception Log::
[4005007.702554] BUG: kernel NULL pointer dereference, address: 0000000000000000
[4005007.702562] #PF: supervisor instruction fetch in kernel mode
[4005007.702567] #PF: error_code(0x0010) - not-present page
[4005007.702570] PGD 0 P4D 0
[4005007.702576] Oops: 0010 [#1] SMP NOPTI
[4005007.702581] CPU: 4 PID: 62563 Comm: cat Tainted: G           OE     5.15.0-43-generic #46-Ubunt       u
[4005007.702590] RIP: 0010:0x0
[4005007.702598] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.702600] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.702605] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.702609] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.702612] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.702615] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.702618] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.702622] FS:  00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.702626] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.702629] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0
[4005007.702633] Call Trace:
[4005007.702636]  <TASK>
[4005007.702640]  amdgpu_debugfs_regs_smc_read+0xb0/0x120 [amdgpu]
[4005007.703002]  full_proxy_read+0x5c/0x80
[4005007.703011]  vfs_read+0x9f/0x1a0
[4005007.703019]  ksys_read+0x67/0xe0
[4005007.703023]  __x64_sys_read+0x19/0x20
[4005007.703028]  do_syscall_64+0x5c/0xc0
[4005007.703034]  ? do_user_addr_fault+0x1e3/0x670
[4005007.703040]  ? exit_to_user_mode_prepare+0x37/0xb0
[4005007.703047]  ? irqentry_exit_to_user_mode+0x9/0x20
[4005007.703052]  ? irqentry_exit+0x19/0x30
[4005007.703057]  ? exc_page_fault+0x89/0x160
[4005007.703062]  ? asm_exc_page_fault+0x8/0x30
[4005007.703068]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[4005007.703075] RIP: 0033:0x7f5e07672992
[4005007.703079] Code: c0 e9 b2 fe ff ff 50 48 8d 3d fa b2 0c 00 e8 c5 1d 02 00 0f 1f 44 00 00 f3 0f        1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 e       c 28 48 89 54 24
[4005007.703083] RSP: 002b:00007ffe03097898 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[4005007.703088] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f5e07672992
[4005007.703091] RDX: 0000000000020000 RSI: 00007f5e06753000 RDI: 0000000000000003
[4005007.703094] RBP: 00007f5e06753000 R08: 00007f5e06752010 R09: 00007f5e06752010
[4005007.703096] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000022000
[4005007.703099] R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
[4005007.703105]  </TASK>
[4005007.703107] Modules linked in: nf_tables libcrc32c nfnetlink algif_hash af_alg binfmt_misc nls_       iso8859_1 ipmi_ssif ast intel_rapl_msr intel_rapl_common drm_vram_helper drm_ttm_helper amd64_edac t       tm edac_mce_amd kvm_amd ccp mac_hid k10temp kvm acpi_ipmi ipmi_si rapl sch_fq_codel ipmi_devintf ipm       i_msghandler msr parport_pc ppdev lp parport mtd pstore_blk efi_pstore ramoops pstore_zone reed_solo       mon ip_tables x_tables autofs4 ib_uverbs ib_core amdgpu(OE) amddrm_ttm_helper(OE) amdttm(OE) iommu_v       2 amd_sched(OE) amdkcl(OE) drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec rc_core        drm igb ahci xhci_pci libahci i2c_piix4 i2c_algo_bit xhci_pci_renesas dca
[4005007.703184] CR2: 0000000000000000
[4005007.703188] ---[ end trace ac65a538d240da39 ]---
[4005007.800865] RIP: 0010:0x0
[4005007.800871] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.800874] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.800878] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.800881] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.800883] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.800886] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.800888] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.800891] FS:  00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.800895] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.800898] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0

Signed-off-by: Qu Huang <qu.huang@linux.dev>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
No milestone
Development

No branches or pull requests
2 participants
@matttbe @pabeni