[moderation] [kernel?] BUG: corrupted list in pwq_release_workfn

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4f79eaa2ceac kbuild: Properly disable -Wunterminated-strin..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1128939b980000
kernel config: https://syzkaller.appspot.com/x/.config?x=541aa584278da96c
dashboard link: https://syzkaller.appspot.com/bug?extid=04a054e3cbc7877cdcd1
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
CC: [b...@alien8.de dave....@linux.intel.com h...@zytor.com linux-...@vger.kernel.org mi...@redhat.com tg...@linutronix.de x...@kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/66f5614381d8/disk-4f79eaa2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1bde5b0c64cb/vmlinux-4f79eaa2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/68ebe592cc39/bzImage-4f79eaa2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+04a054...@syzkaller.appspotmail.com

slab kmalloc-512 start ffff888012ef6800 pointer offset 0 size 512
list_del corruption. next->prev should be ffff88801ef82c88, but was ffffffff9af97480. (next=ffff888012ef6800)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:65!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 3 Comm: pool_workqueue_ Not tainted 6.15.0-rc4-syzkaller-00052-g4f79eaa2ceac #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:__list_del_entry_valid_or_report+0x1b3/0x200 lib/list_debug.c:65
Code: 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 4b 49 8b 54 24 08 4c 89 e1 48 89 de 48 c7 c7 00 83 f4 8b e8 fe 79 c4 fc 90 <0f> 0b e8 e6 a8 4a fd e9 6b fe ff ff 48 89 df e8 d9 a8 4a fd e9 7d
RSP: 0018:ffffc90000087da0 EFLAGS: 00010282
RAX: 000000000000006d RBX: ffff88801ef82c88 RCX: ffffffff819a90e9
RDX: 0000000000000000 RSI: ffffffff819b0f76 RDI: 0000000000000005
RBP: ffff888012ef6808 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 00000000000c50d0 R12: ffff888012ef6800
R13: ffff88801ef82c00 R14: ffff88801ef82c08 R15: ffff88801b492d08
FS: 0000000000000000(0000) GS:ffff888124ae2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd7c95eeb68 CR3: 00000000694b2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__list_del_entry_valid include/linux/list.h:124 [inline]
__list_del_entry include/linux/list.h:215 [inline]
list_del_rcu include/linux/rculist.h:168 [inline]
pwq_release_workfn+0xbc/0xa70 kernel/workqueue.c:5078
kthread_worker_fn+0x30d/0xc50 kernel/kthread.c:1010
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid_or_report+0x1b3/0x200 lib/list_debug.c:65
Code: 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 4b 49 8b 54 24 08 4c 89 e1 48 89 de 48 c7 c7 00 83 f4 8b e8 fe 79 c4 fc 90 <0f> 0b e8 e6 a8 4a fd e9 6b fe ff ff 48 89 df e8 d9 a8 4a fd e9 7d
RSP: 0018:ffffc90000087da0 EFLAGS: 00010282
RAX: 000000000000006d RBX: ffff88801ef82c88 RCX: ffffffff819a90e9
RDX: 0000000000000000 RSI: ffffffff819b0f76 RDI: 0000000000000005
RBP: ffff888012ef6808 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 00000000000c50d0 R12: ffff888012ef6800
R13: ffff88801ef82c00 R14: ffff88801ef82c08 R15: ffff88801b492d08
FS: 0000000000000000(0000) GS:ffff888124ae2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd997d1830 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.