syzbot


WARNING in nf_hook_entry_head (2)

Status: upstream: reported on 2026/01/07 17:34
Subsystems: netfilter
[Documentation on labels]
Reported-by: syzbot+6f6a1d20567a8d6b2a58@syzkaller.appspotmail.com
First crash: 90d, last: 11h59m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [netfilter?] WARNING in nf_hook_entry_head (2) 0 (1) 2026/01/07 17:34
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in nf_hook_entry_head netfilter -1 1 726d 726d 0/29 auto-obsoleted due to no activity on 2024/04/26 12:52

Sample crash report:
------------[ cut here ]------------
WARNING: net/netfilter/core.c:329 at nf_hook_entry_head+0x23e/0x2c0 net/netfilter/core.c:329, CPU#0: kworker/u8:13/4537
Modules linked in:
CPU: 0 UID: 0 PID: 4537 Comm: kworker/u8:13 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: netns cleanup_net
RIP: 0010:nf_hook_entry_head+0x23e/0x2c0 net/netfilter/core.c:329
Code: 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ff e8 5d 76 a7 f8 4d 39 37 74 36 e8 23 56 41 f8 90 <0f> 0b 90 31 db 48 89 d8 5b 41 5e 41 5f 5d e9 5a 9f 90 f7 cc e8 09
RSP: 0018:ffffc9000d997788 EFLAGS: 00010293
RAX: ffffffff897fa15b RBX: ffff888024f18000 RCX: ffff888033515b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff888033515b80 R09: 0000000000000006
R10: 000000000000000a R11: 0000000000000000 R12: ffff8880555f8000
R13: 0000000000000005 R14: ffff8880555f8000 R15: ffff888024f18108
FS:  0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fa18ff8 CR3: 00000000ac7e4000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 __nf_unregister_net_hook+0x74/0x6f0 net/netfilter/core.c:491
 nft_unregister_flowtable_ops net/netfilter/nf_tables_api.c:9038 [inline]
 __nft_unregister_flowtable_net_hooks net/netfilter/nf_tables_api.c:9053 [inline]
 __nft_release_hook+0x180/0x350 net/netfilter/nf_tables_api.c:12035
 __nft_release_hooks net/netfilter/nf_tables_api.c:12049 [inline]
 nf_tables_pre_exit_net+0xa7/0x110 net/netfilter/nf_tables_api.c:12200
 ops_pre_exit_list net/core/net_namespace.c:161 [inline]
 ops_undo_list+0x187/0x990 net/core/net_namespace.c:234
 cleanup_net+0x4d8/0x7a0 net/core/net_namespace.c:696
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

Crashes (40):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/01 13:53 upstream b69053dd3ffb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_hook_entry_head
2025/12/28 22:47 upstream c875a6c32467 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_hook_entry_head
2025/12/19 19:39 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/12/18 19:33 upstream ea1013c15392 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/12/18 11:22 upstream ea1013c15392 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_hook_entry_head
2025/12/17 19:19 upstream ea1013c15392 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/12/17 16:32 upstream ea1013c15392 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/12/16 20:16 upstream 40fbbd64bba6 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/12/16 12:49 upstream 40fbbd64bba6 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/12/12 15:09 upstream 187d0801404f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in nf_hook_entry_head
2025/12/10 05:41 upstream c9b47175e913 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/11/22 15:09 upstream 2eba5e05d9bc 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/11/10 22:03 upstream 4ea7c1717f3f 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/10/30 02:43 upstream e53642b87a4f fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/10/26 07:30 upstream 9bb956508c9d c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/10/14 08:56 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/10/14 08:56 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/10/14 08:37 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2025/10/14 08:31 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in nf_hook_entry_head
2026/01/12 10:53 upstream 0f61b1860cc3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2025/12/31 04:52 upstream dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2025/12/31 04:34 upstream dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2025/12/23 20:33 upstream b927546677c8 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2025/12/20 14:30 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2025/12/02 21:18 upstream 4a26e7032d7d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2025/11/17 11:45 upstream 6a23ae0a96a6 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in nf_hook_entry_head
2026/01/05 14:16 upstream 3609fa95fb0f d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2026/01/04 11:16 upstream aacb0a6d604a d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/12/26 03:27 upstream ccd1cdca5cd4 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/12/25 20:35 upstream ccd1cdca5cd4 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/12/25 13:01 upstream ccd1cdca5cd4 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/12/20 02:04 upstream dd9b004b7ff3 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/12/11 20:58 upstream d358e5254674 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/11/27 16:08 upstream 765e56e41a5a e8331348 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2025/11/20 16:05 upstream 23cb64fb7625 2cc4c24a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in nf_hook_entry_head
2026/01/12 06:11 upstream 9c7ef209cd0f d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in nf_hook_entry_head
2025/12/18 03:34 net 885bebac9909 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in nf_hook_entry_head
2025/12/27 19:30 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in nf_hook_entry_head
2025/10/14 13:06 net-next 3dacc900c00b b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in nf_hook_entry_head
2025/10/17 04:42 linux-next 2433b8476165 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in nf_hook_entry_head
* Struck through repros no longer work on HEAD.