syzbot


WARNING in kcov_task_exit

Status: upstream: reported on 2025/10/05 04:48
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+47cf95ca1f9dcca872c8@syzkaller.appspotmail.com
First crash: 253d, last: now
✨ AI Jobs (3)
ID Workflow Result Correct Ext Bug ID Bug Created Started Finished Revision Error
46754938-6f01-4461-a65e-1a27b2f111de assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in kcov_task_exit 2026/06/01 07:00 2026/06/01 07:00 2026/06/01 08:09 6b4a844333e83556da95d61d7f207e7ef5cd4bc6
36d40745-0ea9-411a-922b-d696de2cd873 assessment-security 💥 WARNING in kcov_task_exit 2026/05/15 10:34 2026/05/15 10:34 2026/05/15 10:35 9cd3beaadf14b3a22d15fd97a0bf081ee41ebe01 failed to run ["git" "-c" "core.hooksPath=/dev/null" "checkout" "70eda68668d1476b459b64e69b8f36659fa9dfa8"]: exit status 128 fatal: sha1 file '/app/workdir/repo/linux/.git/index.lock' write error. Out of diskspace
523e8a01-7718-4f4b-9347-0dc94cdedb36 repro WARNING in kcov_task_exit 2026/03/07 12:39 2026/03/07 12:39 2026/03/07 12:49 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] kcov: fix potential kcov_mode corruption under CONFIG_PREEMPT_RT 5 (5) 2026/05/21 08:38
[syzbot] [kernel?] WARNING in kcov_task_exit 0 (1) 2025/10/05 04:48

Sample crash report:
------------[ cut here ]------------
kcov->t != t
WARNING: kernel/kcov.c:483 at kcov_task_exit+0xf5/0x160 kernel/kcov.c:483, CPU#1: udevd/5850
Modules linked in:
CPU: 1 UID: 0 PID: 5850 Comm: udevd Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:kcov_task_exit+0xf5/0x160 kernel/kcov.c:483
Code: 10 00 00 48 8b bb 90 00 00 00 e8 f6 ce 55 00 48 89 df 5b 41 5e 41 5f e9 c9 8f 5b 00 7c 1c 5b 41 5e 41 5f e9 8d f7 5a 09 cc 90 <0f> 0b 90 4c 89 f7 5b 41 5e 41 5f e9 3b 90 59 09 48 89 df be 03 00
RSP: 0018:ffffc900050dfd20 EFLAGS: 00010206
RAX: 0aaad12535487a00 RBX: ffff88803602de00 RCX: 0000000000000000
RDX: 00000000b32f8fcc RSI: ffffffff8ba75cc0 RDI: 00000000ffffffff
RBP: ffffc900050dfe78 R08: ffffffff8b1dfb60 R09: ffffffff8dfc8100
R10: dffffc0000000000 R11: fffffbfff1f10dff R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88803602de08 R15: ffff88802f395c40
FS:  00007fa2be6a3880(0000) GS:ffff888126287000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555fd64294c8 CR3: 0000000042952000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 do_exit+0x150/0x22c0 kernel/exit.c:909
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119
 __do_sys_exit_group kernel/exit.c:1130 [inline]
 __se_sys_exit_group kernel/exit.c:1128 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1128
 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa2be7db6c5
Code: ff ff ff 64 89 02 eb d2 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 35 21 f7 0f 00 ba e7 00 00 00 eb 03 66 90 f4 89 d0 0f 05 <48> 3d 00 f0 ff ff 76 f3 f7 d8 64 89 06 eb ec 66 2e 0f 1f 84 00 00
RSP: 002b:00007ffd6bc3e148 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000555fd6425810 RCX: 00007fa2be7db6c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 0000555fd6404910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd6bc3e190 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Crashes (15338):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/12 03:16 upstream 2b414a95b8f7 e93da63e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/12 02:00 upstream 2b414a95b8f7 e93da63e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/12 00:55 upstream 2b414a95b8f7 e93da63e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 20:19 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 18:43 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 16:37 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 15:36 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 13:12 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 12:28 upstream 9716c086c8e8 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 09:09 upstream 9716c086c8e8 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 07:09 upstream 9716c086c8e8 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 05:46 upstream 9716c086c8e8 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/11 03:55 upstream 9716c086c8e8 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 20:14 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 20:10 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 17:55 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 16:43 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 14:53 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 14:48 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 09:25 upstream 685441a6d3f1 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 08:01 upstream 685441a6d3f1 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/10 06:15 upstream 685441a6d3f1 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/01 04:51 upstream 8d9c51eac648 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/15 09:47 upstream 70eda68668d1 9cd3beaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/03/07 12:25 upstream 651690480a96 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2025/10/04 19:59 upstream cbf33b8e0b36 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2025/10/01 04:45 upstream 50c19e20ed2e 65a0eece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/06/12 00:08 linux-next ec039126b7fa d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 22:32 linux-next ec039126b7fa d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 21:21 linux-next ec039126b7fa d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 17:42 linux-next ec039126b7fa d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/11 14:30 linux-next abe651837cb3 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 11:17 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/11 08:13 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 03:59 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 02:50 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 01:49 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/11 00:24 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/11 00:04 linux-next abe651837cb3 b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/10 22:55 linux-next abe651837cb3 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 21:48 linux-next abe651837cb3 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 12:59 linux-next 49e02880ec0a f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 11:51 linux-next 49e02880ec0a f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/10 10:51 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 07:25 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/10 04:59 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 03:50 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 03:33 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/06/10 02:11 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/06/10 00:53 linux-next 49e02880ec0a 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
* Struck through repros no longer work on HEAD.