syzbot


WARNING in zap_other_threads

Status: upstream: reported C repro on 2025/10/11 23:24
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+3a0361dab1c9bdba8524@syzkaller.appspotmail.com
First crash: 152d, last: 147d
Fix bisection: failed (error log)
  
Bug presence (2)
Date Name Commit Repro Result
2025/10/17 linux-6.6.y (ToT) 0bbbd97a442d C [report] WARNING in zap_other_threads
2025/10/17 upstream (ToT) 98ac9cc4b445 C Didn't crash
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/12/28 22:04 1h33m fix candidate upstream OK (0) job log
2025/11/18 21:36 0m bisect fix linux-6.6.y error

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5962 at kernel/signal.c:772 signal_wake_up_state kernel/signal.c:772 [inline]
WARNING: CPU: 0 PID: 5962 at kernel/signal.c:772 signal_wake_up include/linux/sched/signal.h:457 [inline]
WARNING: CPU: 0 PID: 5962 at kernel/signal.c:772 zap_other_threads+0x38e/0x440 kernel/signal.c:1396
Modules linked in:
CPU: 0 PID: 5962 Comm: file0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:signal_wake_up_state kernel/signal.c:772 [inline]
RIP: 0010:signal_wake_up include/linux/sched/signal.h:457 [inline]
RIP: 0010:zap_other_threads+0x38e/0x440 kernel/signal.c:1396
Code: 89 00 48 81 e5 ff ff c0 ff 49 89 6d 00 f0 83 44 24 fc 00 4c 89 ef be 15 00 00 00 e8 ac c3 10 00 e9 85 fd ff ff e8 c2 01 32 00 <0f> 0b e9 26 ff ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 8f fd ff
RSP: 0000:ffffc90002e57c20 EFLAGS: 00010093
RAX: ffffffff8153890e RBX: 1ffff11005c6e46c RCX: ffff88802e223c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000109 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520005caf6c R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffff88802e371e00
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000000000025d CR3: 0000000075c64000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 do_group_exit+0x197/0x2d0 kernel/exit.c:1019
 get_signal+0x12fc/0x1400 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:315
 exc_page_fault+0x8f/0x110 arch/x86/mm/fault.c:1524
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0023:0x25d
Code: Unable to access opcode bytes at 0x233.
RSP: 002b:00000000ffb1c110 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/12 07:24 linux-6.6.y e617101e5626 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
2025/10/12 05:56 linux-6.6.y e617101e5626 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
2025/10/12 04:31 linux-6.6.y e617101e5626 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
2025/10/12 03:09 linux-6.6.y e617101e5626 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
2025/10/12 02:07 linux-6.6.y e617101e5626 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
2025/10/12 00:45 linux-6.6.y e617101e5626 ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
2025/10/11 23:23 linux-6.6.y e617101e5626 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in zap_other_threads
* Struck through repros no longer work on HEAD.