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BUG: corrupted list in remove_wait_queue (2)

Status: upstream: reported C repro on 2025/01/22 23:27
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+4e21d5f67b886a692b55@syzkaller.appspotmail.com
First crash: 470d, last: 74d
Cause bisection: introduced by (bisect log) :
commit 8ffdff6a8cfbdc174a3a390b6f825a277b5bb895
Author: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Wed Apr 14 08:58:10 2021 +0000

  staging: comedi: move out of staging directory

Crash: KASAN: use-after-free Read in remove_wait_queue (log)
Repro: C syz .config
  
Fix bisection: fixed by (bisect log) :
commit 35b6fc51c666fc96355be5cd633ed0fe4ccf68b2
Author: Ian Abbott <abbotti@mev.co.uk>
Date: Tue Jul 22 15:53:16 2025 +0000

  comedi: fix race between polling and detaching

  
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[syzbot] [fs?] BUG: corrupted list in remove_wait_queue (2) 1 (6) 2026/01/15 23:32
[PATCH v2] media: dmxdev: fix repeated initialization of ringbuffer in dvb_dvr_open() 1 (1) 2025/04/07 09:16
[PATCH] media: dmxdev: fix repeated initialization of ringbuffer in dvb_dvr_open() 1 (1) 2025/04/06 16:58
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 BUG: corrupted list in remove_wait_queue 8 C 31139 1154d 2581d 0/1 upstream: reported C repro on 2019/04/10 16:06
upstream BUG: corrupted list in remove_wait_queue virt kvm net 8 C 5 2963d 2966d 5/29 fixed on 2018/04/06 16:37
upstream KASAN: use-after-free Read in remove_wait_queue (3) kernfs 19 C inconclusive 123 1204d 1630d 22/29 fixed on 2023/02/24 13:50
linux-4.14 KASAN: use-after-free Read in remove_wait_queue (2) 19 C error 7 1522d 2218d 0/1 upstream: reported C repro on 2020/04/07 06:03
linux-5.15 KASAN: use-after-free Read in remove_wait_queue 19 C done 25 253d 274d 2/3 upstream: reported C repro on 2025/08/03 00:30
upstream KASAN: slab-use-after-free Read in remove_wait_queue input usb 19 3 1046d 1047d 0/29 auto-obsoleted due to no activity on 2023/10/01 17:55
linux-6.6 KASAN: slab-use-after-free Read in remove_wait_queue 19 syz 13 249d 274d 0/2 auto-obsoleted due to no activity on 2025/11/06 12:40
linux-6.1 KASAN: use-after-free Read in remove_wait_queue origin:lts-only 19 C error 24 253d 274d 0/3 upstream: reported C repro on 2025/08/03 01:02
▶ ▼ Last patch testing requests (12)
Created Duration User Patch Repo Result
2026/04/14 10:03 1h07m retest repro upstream OK log
2026/04/14 10:03 23m retest repro upstream OK log
2026/04/14 08:29 24m retest repro upstream OK log
2026/04/14 08:29 24m retest repro upstream OK log
2026/04/14 08:01 25m retest repro upstream OK log
2026/03/05 00:29 21m retest repro upstream OK log
2026/02/03 08:44 14m retest repro upstream error
2026/02/03 07:40 13m retest repro upstream error
2026/02/03 07:40 13m retest repro upstream error
2026/02/03 07:40 13m retest repro upstream error
2025/07/07 11:27 15m hdanton@sina.com patch upstream report log
2025/02/17 07:26 21m lizhi.xu@windriver.com patch upstream error

Sample crash report:
 slab kmalloc-8k start ffff8881477b0000 pointer offset 1480 size 8192
list_del corruption. prev->next should be ffff88805cfec0e8, but was ffff8881477b05c8. (prev=ffff8881477b05c8)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:62!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 8313 Comm: syz.3.449 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__list_del_entry_valid_or_report+0x17a/0x200 lib/list_debug.c:62
Code: 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 8d 00 00 00 48 8b 55 00 48 89 e9 48 89 de 48 c7 c7 a0 7d f0 8b e8 87 18 f1 fc 90 <0f> 0b 4c 89 e7 e8 ac 09 56 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc9000b107c10 EFLAGS: 00010086
RAX: 000000000000006d RBX: ffff88805cfec0e8 RCX: ffffffff819ada09
RDX: 0000000000000000 RSI: ffffffff819b5536 RDI: 0000000000000005
RBP: ffff8881477b05c8 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000001 R11: 0000000000000001 R12: ffff8881477b05c8
R13: ffff88805cfec0e8 R14: ffff88805cfec0f0 R15: ffff88805cfec0c0
FS:  0000000000000000(0000) GS:ffff888124a0d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f08f11ed990 CR3: 000000007584c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:223 [inline]
 list_del include/linux/list.h:237 [inline]
 __remove_wait_queue include/linux/wait.h:209 [inline]
 remove_wait_queue+0x30/0x180 kernel/sched/wait.c:74
 ep_remove_wait_queue+0x85/0x1d0 fs/eventpoll.c:676
 ep_unregister_pollwait fs/eventpoll.c:691 [inline]
 ep_clear_and_put+0x186/0x420 fs/eventpoll.c:916
 ep_eventpoll_release+0x3e/0x60 fs/eventpoll.c:966
 __fput+0x402/0xb70 fs/file_table.c:468
 task_work_run+0x150/0x240 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x86f/0x2bf0 kernel/exit.c:966
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1107
 __do_sys_exit_group kernel/exit.c:1118 [inline]
 __se_sys_exit_group kernel/exit.c:1116 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1116
 x64_sys_call+0x150b/0x1730 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f1ed8f7c9
Code: Unable to access opcode bytes at 0x7f6f1ed8f79f.
RSP: 002b:00007ffceb7a6328 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6f1ed8f7c9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffceb7a638c R08: 0000001eeb7a641f R09: 00000000000927c0
R10: 0000000000043094 R11: 0000000000000246 R12: 000000000000006f
R13: 00000000000927c0 R14: 0000000000040d27 R15: 00007ffceb7a63e0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid_or_report+0x17a/0x200 lib/list_debug.c:62
Code: 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 8d 00 00 00 48 8b 55 00 48 89 e9 48 89 de 48 c7 c7 a0 7d f0 8b e8 87 18 f1 fc 90 <0f> 0b 4c 89 e7 e8 ac 09 56 fd 48 89 ea 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc9000b107c10 EFLAGS: 00010086
RAX: 000000000000006d RBX: ffff88805cfec0e8 RCX: ffffffff819ada09
RDX: 0000000000000000 RSI: ffffffff819b5536 RDI: 0000000000000005
RBP: ffff8881477b05c8 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000001 R11: 0000000000000001 R12: ffff8881477b05c8
R13: ffff88805cfec0e8 R14: ffff88805cfec0f0 R15: ffff88805cfec0c0
FS:  0000000000000000(0000) GS:ffff888124a0d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f08f11ed990 CR3: 000000007584c000 CR4: 00000000003526f0

Crashes (61):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/01 17:19 upstream 7d0a66e4bb90 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/11/29 12:27 upstream 19eef1d98eed d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/11/28 06:27 upstream aa7243aaf194 e8331348 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/11/11 05:43 upstream 4ea7c1717f3f 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/11/08 15:17 upstream e811c33b1f13 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/10/17 04:00 upstream 634ec1fc7982 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/10/06 06:28 upstream 6a74422b9710 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/09/16 18:22 upstream 46a51f4f5eda e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/19 17:38 upstream fda5e3f28400 f2cb035c .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/19 15:02 upstream fda5e3f28400 f2cb035c .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/19 12:45 upstream fda5e3f28400 f2cb035c .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/19 10:38 upstream fda5e3f28400 f2cb035c .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/19 08:27 upstream fda5e3f28400 f2cb035c .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/19 06:05 upstream fda5e3f28400 f2cb035c .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2025/01/18 23:22 upstream 595523945be0 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: corrupted list in remove_wait_queue
2026/02/19 00:07 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 BUG: corrupted list in remove_wait_queue
2026/02/16 09:53 upstream 26a4cfaff82a 1e62d198 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: corrupted list in remove_wait_queue
2025/08/21 19:13 upstream 038d61fd6422 0b9605c8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/20 16:35 upstream 038d61fd6422 bd178e57 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/20 03:26 upstream 038d61fd6422 79512909 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/20 02:16 upstream 038d61fd6422 79512909 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/19 11:22 upstream 038d61fd6422 523f460e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/19 05:08 upstream 038d61fd6422 523f460e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/17 06:17 upstream 038d61fd6422 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/11 07:05 upstream 038d61fd6422 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/06 14:04 upstream 038d61fd6422 4bd24a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/06 08:00 upstream 038d61fd6422 904e669c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/03 13:15 upstream 038d61fd6422 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/08/03 11:19 upstream 038d61fd6422 7368264b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/30 06:15 upstream 038d61fd6422 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/30 00:44 upstream ced1b9e0392d f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/30 00:44 upstream ced1b9e0392d f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/29 21:18 upstream 038d61fd6422 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/27 18:24 upstream b711733e89a3 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/26 22:24 upstream 5f33ebd2018c fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/24 09:48 upstream 01a412d06bc5 0c1d6ded .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/17 19:46 upstream e2291551827f 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/09 21:55 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/09 03:21 upstream d006330be3f7 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/09 03:21 upstream d006330be3f7 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/08 23:29 upstream d006330be3f7 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/08 23:28 upstream d006330be3f7 abade794 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/06 03:06 upstream 05df91921da6 4f67c4ae .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/06 02:10 upstream 05df91921da6 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/28 15:32 upstream 038d61fd6422 032c6886 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/28 07:47 upstream b711733e89a3 fb8f743d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/26 09:58 upstream 5f33ebd2018c fb8f743d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/25 13:27 upstream 94ce1ac2c9b4 fb8f743d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/25 02:30 upstream 94ce1ac2c9b4 fb8f743d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/23 16:41 upstream 89be9a83ccf1 e0b9ac93 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/21 04:44 upstream 990b11a523a8 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/20 10:27 upstream f4a40a4282f4 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/20 09:42 upstream f4a40a4282f4 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/19 10:20 upstream c7de79e662b8 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/15 17:48 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/13 13:56 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/10 13:49 upstream 8c2e52ebbe88 d7384b6d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/13 13:22 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-use-after-free Read in remove_wait_queue
2025/07/10 00:50 linux-next 835244aba90d f4e5e155 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce KASAN: slab-use-after-free Read in remove_wait_queue
* Struck through repros no longer work on HEAD.