syzbot


INFO: task hung in nfnetlink_rcv_msg (5)

Status: upstream: reported on 2026/01/02 02:25
Subsystems: netfilter
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+c4b20b80ee6a7a2f5012@syzkaller.appspotmail.com
First crash: 255d, last: 3h09m
✨ AI Jobs (3)
ID Workflow Result Correct Bug Created Started Finished Revision Error
eaf8606b-99cf-44a7-a9d0-d4f91c8607e7 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in nfnetlink_rcv_msg (5) 2026/05/31 05:27 2026/05/31 05:27 2026/05/31 06:24 6b4a844333e83556da95d61d7f207e7ef5cd4bc6

			
		
14c49c67-419d-41a1-aa47-7ec365a6a500 assessment-security 💥 INFO: task hung in nfnetlink_rcv_msg (5) 2026/05/14 14:14 2026/05/14 14:14 2026/05/14 14:15 6ccb967e465e832a7bfd7a116ad00d52a0923a5d
failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128
From /app/workdir/repo/linux
 * branch                HEAD       -> FETCH_HEAD
Updating files:  ...
truncated to first 200 bytes; open job for full error
e8644a53-5bf0-421c-a48b-41290e12f37a repro INFO: task hung in nfnetlink_rcv_msg (5) 2026/03/06 20:29 2026/03/06 20:29 2026/03/06 20:43 31e9c887f7dc24e04b3ca70d0d54fc34141844b0

			
		
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] Monthly netfilter report (Apr 2026) 0 (1) 2026/04/29 20:32
[syzbot] Monthly netfilter report (Mar 2026) 0 (1) 2026/03/31 08:07
[syzbot] [netfilter?] INFO: task hung in nfnetlink_rcv_msg (5) 0 (1) 2026/01/02 02:25
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in nfnetlink_rcv_msg (4) netfilter 1 2 388d 448d 0/29 auto-obsoleted due to no activity on 2025/08/22 01:09
upstream INFO: task hung in nfnetlink_rcv_msg (3) netfilter 1 C done 5 1284d 1295d 22/29 fixed on 2023/06/08 14:41
upstream INFO: task hung in nfnetlink_rcv_msg netfilter 1 30 2043d 2352d 0/29 auto-closed as invalid on 2021/03/11 10:49
upstream INFO: task hung in nfnetlink_rcv_msg (2) netfilter 1 1 1679d 1679d 0/29 auto-closed as invalid on 2022/02/07 23:39

Sample crash report:
INFO: task syz.5.1086:11661 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1086      state:D stack:28208 pid:11661 tgid:11656 ppid:11379  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5504 [inline]
 __schedule+0x125c/0x6730 kernel/sched/core.c:7228
 __schedule_loop kernel/sched/core.c:7307 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7322
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821
 nfnl_lock net/netfilter/nfnetlink.c:96 [inline]
 nfnetlink_rcv_msg+0x8ad/0x11e0 net/netfilter/nfnetlink.c:293
 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2555
 nfnetlink_rcv+0x1b3/0x440 net/netfilter/nfnetlink.c:667
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1344

Crashes (77):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/16 14:31 upstream 481329ec5b31 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfnetlink_rcv_msg
2026/05/10 16:08 upstream 1bfaee9d3351 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/05/08 02:52 upstream 19cbc75c56c0 e358bca5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfnetlink_rcv_msg
2026/04/24 17:48 upstream dd6c438c3e64 1c2b9291 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfnetlink_rcv_msg
2026/04/14 02:17 upstream 0f0013213293 1a086e7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfnetlink_rcv_msg
2026/04/08 08:34 upstream 3036cd0d3328 2c961e87 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/03/30 06:46 upstream f242ac4a0944 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/20 13:03 upstream 24d479d26b25 572effc1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/19 09:06 upstream 24d479d26b25 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfnetlink_rcv_msg
2026/01/15 11:08 upstream 944aacb68baf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/15 05:43 upstream 944aacb68baf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfnetlink_rcv_msg
2026/01/14 13:05 upstream c537e12daeec d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/13 21:27 upstream b54345928fa1 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfnetlink_rcv_msg
2026/01/13 14:55 upstream b71e635feefc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/13 08:29 upstream b71e635feefc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfnetlink_rcv_msg
2026/01/12 14:40 upstream 7143203341dc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/10 07:37 upstream c9b47175e913 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/10/28 23:29 upstream 8eefed8f65cc fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/02/07 22:02 upstream e7aa57247700 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in nfnetlink_rcv_msg
2026/01/14 22:15 upstream c537e12daeec d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in nfnetlink_rcv_msg
2026/04/17 03:54 net 52bcb57a4e8a de0a551d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/05/01 13:39 net-next edf4bee4215a 753c55b9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/03/31 15:38 net-next 93d04e76bcf1 aeea1c72 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/03/29 17:11 net-next ced629dc8e5c 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/03/16 05:40 net-next 5446b8691eb8 ee8d34d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/03/07 23:04 net-next 0bcac7b11262 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/24 13:14 net-next eac026ff97a9 4f25b9b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/07 06:33 net-next 8e7148b56023 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/07 03:36 net-next 956f569c90ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/07 02:30 net-next 956f569c90ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/06 22:44 net-next 956f569c90ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/06 19:52 net-next 956f569c90ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/06 17:21 net-next 956f569c90ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/06 03:31 net-next 32291cb0369a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/04 20:30 net-next c303e8b86d9d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/03 01:42 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/03 01:02 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/02 13:36 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/02 12:26 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/02 11:48 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/01 17:28 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/30 19:17 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/29 08:29 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/29 05:47 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/29 02:18 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/28 23:56 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/28 18:14 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/28 11:14 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/28 01:05 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/28 00:46 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/28 00:08 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/27 09:50 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/26 18:31 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/26 10:49 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/26 08:25 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/26 07:09 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/26 04:07 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/25 20:31 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/25 18:45 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/25 02:06 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/24 11:08 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/24 03:12 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/23 21:00 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/22 23:55 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/21 22:34 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/21 13:54 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/21 06:07 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/21 04:52 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/20 22:38 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/20 07:25 net-next 7b8e9264f55a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2026/01/14 11:26 linux-next b775e489bec7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/12/29 06:50 linux-next cc3aa43b44bd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in nfnetlink_rcv_msg
2025/12/07 07:01 linux-next 6987d58a9cbc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfnetlink_rcv_msg
2025/10/04 03:28 linux-next 47a8d4b89844 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfnetlink_rcv_msg
* Struck through repros no longer work on HEAD.