syzbot


BUG: corrupted list in pwq_release_workfn

Status: moderation: reported on 2025/05/05 19:10
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+04a054e3cbc7877cdcd1@syzkaller.appspotmail.com
First crash: 6d20h, last: 6d20h
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in pwq_release_workfn kernel C unreliable 79 566d 616d 25/28 fixed on 2023/12/21 03:45

Sample crash report:
 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

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/01 19:00 upstream 4f79eaa2ceac 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: corrupted list in pwq_release_workfn
* Struck through repros no longer work on HEAD.