BUG: corrupted list in io_poll_task_func

[Wei Chen]

Dear Linux Developer,

Recently when using our tool to fuzz kernel, the following crash was triggered:

HEAD commit: c5eb0a61238d Linux 5.18-rc6
git tree: upstream
compiler: clang 12.0.0
console output:
https://drive.google.com/file/d/1Obzlp9wrLFx9BogwmOHhmnQqyMYa2z_k/view?usp=sharing
kernel config: https://drive.google.com/file/d/12fNP5UArsFqTi2jjGomWuCk5evtgU0Gu/view?usp=sharing

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: Wei Chen <harperchen1110@xxxxxxxxx>

list_del corruption. prev->next should be ffff88810ec0ae30, but was
ffff888114119218. (prev=ffff888114119218)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:53!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 20805 Comm: iou-sqp-20802 Not tainted 5.18.0-rc6 #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:__list_del_entry_valid+0xa7/0xc0
Code: 48 c7 c7 54 12 3f 83 4c 89 fe 48 89 da 31 c0 e8 89 e0 21 01 0f
0b 48 c7 c7 6f d7 48 83 4c 89 fe 4c 89 e1 31 c0 e8 73 e0 21 01 <0f> 0b
48 c7 c7 17 b4 42 83 4c 89 fe 4c 89 f1 31 c0 e8 5d e0 21 01
RSP: 0018:ffffc900026dbb58 EFLAGS: 00010046
RAX: 000000000000006d RBX: dead000000000122 RCX: 6101d1e720e71900
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88810ec0ae08 R08: ffffffff8115f303 R09: 0000000000000000
R10: 0001ffffffffffff R11: 000188813bc1b460 R12: ffff888114119218
R13: ffff88810ec0ae00 R14: ffff888114119218 R15: ffff88810ec0ae30
FS:  00007f1e57534700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e574afdb8 CR3: 00000001394b3000 CR4: 0000000000750ef0
DR0: 0000000020000140 DR1: 0000000020000440 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
PKRU: 55555554
Call Trace:
 <TASK>
 io_poll_task_func+0x1ca/0x4f0
 tctx_task_work+0x808/0xae0
 task_work_run+0x8e/0x110
 get_signal+0x13c6/0x1520
 io_sq_thread+0x382/0xbd0
 ret_from_fork+0x1f/0x30
 </TASK>
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid+0xa7/0xc0
Code: 48 c7 c7 54 12 3f 83 4c 89 fe 48 89 da 31 c0 e8 89 e0 21 01 0f
0b 48 c7 c7 6f d7 48 83 4c 89 fe 4c 89 e1 31 c0 e8 73 e0 21 01 <0f> 0b
48 c7 c7 17 b4 42 83 4c 89 fe 4c 89 f1 31 c0 e8 5d e0 21 01
RSP: 0018:ffffc900026dbb58 EFLAGS: 00010046
RAX: 000000000000006d RBX: dead000000000122 RCX: 6101d1e720e71900
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88810ec0ae08 R08: ffffffff8115f303 R09: 0000000000000000
R10: 0001ffffffffffff R11: 000188813bc1b460 R12: ffff888114119218
R13: ffff88810ec0ae00 R14: ffff888114119218 R15: ffff88810ec0ae30
FS:  00007f1e57534700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e574afdb8 CR3: 00000001394b3000 CR4: 0000000000750ef0
DR0: 0000000020000140 DR1: 0000000020000440 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
PKRU: 55555554

Best,
Wei