INFO: task hung in rtnetlink_rcv_msg (2)

Status: upstream: reported on 2026/05/16 14:21
Reported-by: syzbot+40666be185ef012c4b9a@syzkaller.appspotmail.com
First crash: 173d, last: 6d14h
▶ ▼ Similar bugs (19)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in rtnetlink_rcv_msg 1 1 1210d 1210d 0/3 auto-obsoleted due to no activity on 2023/10/22 21:13
linux-4.19 INFO: task hung in rtnetlink_rcv_msg (2) 1 14 1752d 1932d 0/1 auto-closed as invalid on 2022/05/18 11:30
linux-4.19 INFO: task hung in rtnetlink_rcv_msg (3) 1 8 1365d 1599d 0/1 upstream: reported on 2022/06/20 23:55
linux-4.19 INFO: task hung in rtnetlink_rcv_msg 1 11 2184d 2506d 0/1 auto-closed as invalid on 2021/03/12 19:03
upstream INFO: task hung in rtnetlink_rcv_msg (2) net 1 syz, C inconclusive 548 591d 800d 0/29 closed as invalid on 2025/04/18 16:40
linux-5.15 INFO: task hung in rtnetlink_rcv_msg (4) origin:upstream 1 syz 5 26d 215d 0/3 upstream: reported syz repro on 2026/04/05 04:20
upstream INFO: task hung in rtnetlink_rcv_msg (4) prio:normal net 1 syz 59 32d 424d 0/29 closed as invalid on 2026/10/06 01:41
linux-6.1 INFO: task hung in rtnetlink_rcv_msg (3) origin:upstream 1 syz, C error 25 47d 777d 0/3 upstream: reported C repro on 2024/09/19 14:16
linux-5.15 INFO: task hung in rtnetlink_rcv_msg (3) 1 1 568d 568d 0/3 auto-obsoleted due to no activity on 2025/07/26 04:34
upstream INFO: task hung in rtnetlink_rcv_msg net 1 syz, C inconclusive inconclusive 1970 850d 2813d 26/29 fixed on 2024/07/09 19:14
linux-4.14 INFO: task hung in rtnetlink_rcv_msg 1 1 1345d 1345d 0/1 upstream: reported on 2023/03/01 21:15
linux-5.15 INFO: task hung in rtnetlink_rcv_msg (2) 1 70 720d 1012d 0/3 auto-obsoleted due to no activity on 2025/01/24 13:11
android-6-12 INFO: task hung in rtnetlink_rcv_msg (2) 1 253 1d11h 288d 0/1 premoderation: reported on 2026/01/21 16:59
linux-6.1 INFO: task hung in rtnetlink_rcv_msg (2) 1 67 849d 1014d 0/3 auto-obsoleted due to no activity on 2024/09/17 07:45
linux-6.1 INFO: task hung in rtnetlink_rcv_msg 1 1 1135d 1135d 0/3 auto-obsoleted due to no activity on 2024/01/09 18:18
android-6-12 INFO: task hung in rtnetlink_rcv_msg 1 265 357d 502d 0/1 auto-obsoleted due to no activity on 2026/01/02 16:22
linux-6.6 INFO: task hung in rtnetlink_rcv_msg 1 3 276d 368d 0/2 auto-obsoleted due to no activity on 2026/05/14 04:07
upstream INFO: task hung in rtnetlink_rcv_msg (3) net 1 4 518d 558d 0/29 auto-obsoleted due to no activity on 2025/09/03 19:16
upstream INFO: task hung in cangw_pernet_exit (3) can 1 syz unreliable 290 1774d 1880d 0/29 closed as invalid on 2022/02/08 10:22

Sample crash report:
INFO: task syz-executor:14053 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22280 pid:14053 ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5393 [inline]
 __schedule+0x156f/0x4720 kernel/sched/core.c:6722
 schedule+0xbd/0x170 kernel/sched/core.c:6796
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6855
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x689/0xce0 kernel/locking/mutex.c:747
 rtnl_lock net/core/rtnetlink.c:78 [inline]
 rtnetlink_rcv_msg+0x7ed/0xf90 net/core/rtnetlink.c:6486
 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2554
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x856/0x9e0 net/netlink/af_netlink.c:1346

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/30 15:59 linux-6.6.y b5a1dc3ad482 b498adee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in rtnetlink_rcv_msg
2026/10/28 05:28 linux-6.6.y 0aebf2870d53 96923c60 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in rtnetlink_rcv_msg
2026/10/08 15:17 linux-6.6.y a91a6aa9253c 4f6a9fcf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in rtnetlink_rcv_msg
2026/09/29 07:11 linux-6.6.y 79643295eba1 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: task hung in rtnetlink_rcv_msg
2026/09/10 21:55 linux-6.6.y 8b73de7da85f 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in rtnetlink_rcv_msg
2026/08/09 17:45 linux-6.6.y 6436c12a2ced 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in rtnetlink_rcv_msg
2026/07/07 23:07 linux-6.6.y da47cbc25466 76cdc0c0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in rtnetlink_rcv_msg
2026/05/16 14:20 linux-6.6.y 4d922539ad7d a15a64a6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in rtnetlink_rcv_msg
* Struck through repros no longer work on HEAD.