syzbot


general protection fault in io_ring_exit_work

Status: auto-closed as invalid on 2022/02/27 16:41
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+00d5d9e6172cd6384b9a@syzkaller.appspotmail.com
First crash: 906d, last: 878d

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 148 Comm: kworker/u4:2 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound io_ring_exit_work
RIP: 0010:__list_del_entry_valid+0xa9/0xf0 lib/list_debug.c:54
Code: ea 03 80 3c 02 00 75 51 49 8b 14 24 48 39 ea 0f 85 92 e7 23 05 49 8d 7d 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 22 49 8b 55 08 48 39 ea 0f 85 a3 e7 23 05 5d b8 01
RSP: 0018:ffffc9000174fb70 EFLAGS: 00010212
RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff81e3305b RDI: 0000000000000008
RBP: ffff888000101000 R08: 00000000ffffffff R09: ffffffff8fd01ad7
R10: ffffffff81e33136 R11: 0000000000086089 R12: ffff888072112ac0
R13: 0000000000000000 R14: ffff888072112ac0 R15: ffff888000101008
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561e88aa2fd8 CR3: 000000007a5ca000 CR4: 0000000000350ef0
Call Trace:
 __list_del_entry include/linux/list.h:132 [inline]
 list_del include/linux/list.h:146 [inline]
 __io_remove_buffers fs/io_uring.c:4303 [inline]
 __io_remove_buffers fs/io_uring.c:4289 [inline]
 io_destroy_buffers fs/io_uring.c:9213 [inline]
 io_ring_ctx_free fs/io_uring.c:9272 [inline]
 io_ring_exit_work+0xaeb/0x19a0 fs/io_uring.c:9446
 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Modules linked in:
---[ end trace 0e8a2174890a75da ]---
RIP: 0010:__list_del_entry_valid+0xa9/0xf0 lib/list_debug.c:54
Code: ea 03 80 3c 02 00 75 51 49 8b 14 24 48 39 ea 0f 85 92 e7 23 05 49 8d 7d 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 22 49 8b 55 08 48 39 ea 0f 85 a3 e7 23 05 5d b8 01
RSP: 0018:ffffc9000174fb70 EFLAGS: 00010212

RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff81e3305b RDI: 0000000000000008
RBP: ffff888000101000 R08: 00000000ffffffff R09: ffffffff8fd01ad7
R10: ffffffff81e33136 R11: 0000000000086089 R12: ffff888072112ac0
R13: 0000000000000000 R14: ffff888072112ac0 R15: ffff888000101008
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561e88b42087 CR3: 00000000194f8000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	03 80 3c 02 00 75    	add    0x7500023c(%rax),%eax
   6:	51                   	push   %rcx
   7:	49 8b 14 24          	mov    (%r12),%rdx
   b:	48 39 ea             	cmp    %rbp,%rdx
   e:	0f 85 92 e7 23 05    	jne    0x523e7a6
  14:	49 8d 7d 08          	lea    0x8(%r13),%rdi
  18:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1f:	fc ff df
  22:	48 89 fa             	mov    %rdi,%rdx
  25:	48 c1 ea 03          	shr    $0x3,%rdx
* 29:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2d:	75 22                	jne    0x51
  2f:	49 8b 55 08          	mov    0x8(%r13),%rdx
  33:	48 39 ea             	cmp    %rbp,%rdx
  36:	0f 85 a3 e7 23 05    	jne    0x523e7df
  3c:	5d                   	pop    %rbp
  3d:	b8                   	.byte 0xb8
  3e:	01                   	.byte 0x1

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/11/01 22:16 upstream 8bb7eca972ad 098b5d53 .config console log report info ci-upstream-kasan-gce-root general protection fault in io_ring_exit_work
2021/11/29 16:40 https://github.com/google/kmsan.git master a535b0caaa2f d0830353 .config console log report info ci-upstream-kmsan-gce KMSAN: uninit-value in io_ring_exit_work
* Struck through repros no longer work on HEAD.