INFO: task hung in rtnetlink_rcv_msg (2)

Status: premoderation: reported on 2026/01/21 16:59
Reported-by: syzbot+c8594a8ad43127762feb@syzkaller.appspotmail.com
First crash: 190d, last: 17h22m
▶ ▼ Similar bugs (18)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: task hung in rtnetlink_rcv_msg (2) 1 2 23d 76d 0/2 upstream: reported on 2026/05/16 14:21
linux-5.15 INFO: task hung in rtnetlink_rcv_msg 1 1 1112d 1112d 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 1655d 1834d 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 1267d 1501d 0/1 upstream: reported on 2022/06/20 23:55
linux-4.19 INFO: task hung in rtnetlink_rcv_msg 1 11 2086d 2408d 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 494d 702d 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 4 11d 117d 0/3 upstream: reported syz repro on 2026/04/05 04:20
linux-6.1 INFO: task hung in rtnetlink_rcv_msg (3) origin:upstream 1 syz, C error 21 118d 680d 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 470d 470d 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 752d 2715d 26/29 fixed on 2024/07/09 19:14
linux-4.14 INFO: task hung in rtnetlink_rcv_msg 1 1 1247d 1247d 0/1 upstream: reported on 2023/03/01 21:15
linux-5.15 INFO: task hung in rtnetlink_rcv_msg (2) 1 70 623d 914d 0/3 auto-obsoleted due to no activity on 2025/01/24 13:11
linux-6.1 INFO: task hung in rtnetlink_rcv_msg (2) 1 67 752d 916d 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 1037d 1037d 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 259d 405d 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 178d 270d 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 420d 461d 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 1676d 1782d 0/29 closed as invalid on 2022/02/08 10:22

Sample crash report:
INFO: task syz-executor:602 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:602   tgid:602   ppid:1      flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6060 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7880
 __schedule_loop kernel/sched/core.c:7957 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7972
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676
 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x68d/0x700 net/socket.c:2216
 __do_sys_sendto net/socket.c:2228 [inline]
 __se_sys_sendto net/socket.c:2224 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2224
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff359559197
RSP: 002b:00007ffde3cdb590 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055557e4ff500 RCX: 00007ff359559197
RDX: 000000000000002c RSI: 00007ff35a354670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffde3cdb5f4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007ff35a354670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:605 blocked for more than 125 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:605   tgid:605   ppid:1      flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6060 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7880
 __schedule_loop kernel/sched/core.c:7957 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7972
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676
 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x68d/0x700 net/socket.c:2216
 __do_sys_sendto net/socket.c:2228 [inline]
 __se_sys_sendto net/socket.c:2224 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2224
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f4d3eb59197
RSP: 002b:00007ffd400181b0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055556b75e500 RCX: 00007f4d3eb59197
RDX: 000000000000002c RSI: 00007f4d3f954670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffd40018214 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f4d3f954670 R15: 0000000000000000
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b31bef96cff8e44f9e14c4f768eb06c85e3b290
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xe45/0xf90 kernel/hung_task.c:423
 kthread+0x2c7/0x360 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 0b31bef96cff8e44f9e14c4f768eb06c85e3b290
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:update_stack_state+0x102/0x4d0 arch/x86/kernel/unwind_frame.c:-1
Code: 41 c6 06 01 b8 a8 00 00 00 49 89 d6 eb 05 b8 10 00 00 00 4d 8d 65 08 49 8d 4d 10 4c 89 75 b8 4c 01 f0 48 89 45 80 49 8d 55 18 <49> 8d 45 28 49 8d 75 20 48 89 b5 68 ff ff ff 4c 89 e6 48 c1 ee 03
RSP: 0018:ffffc9000022fea8 EFLAGS: 00000286
RAX: ffffc90000230960 RBX: ffffc9000022ffc8 RCX: ffffc9000022ffd8
RDX: ffffc9000022ffe0 RSI: ffffc90000230950 RDI: ffffc90000230020
RBP: ffffc9000022ff58 R08: ffffc90000230090 R09: ffffc90000230088
R10: 000000000000000c R11: ffffffff81759ed0 R12: ffffc9000022ffd0
R13: ffffc9000022ffc8 R14: ffffc90000230950 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0f029f84c0 CR3: 000000010b714000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 unwind_next_frame+0x39e/0x6b0 arch/x86/kernel/unwind_frame.c:315
 arch_stack_walk+0x138/0x170 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:49 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
 kasan_save_free_info+0x44/0x50 mm/kasan/generic.c:579

Crashes (213):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/30 21:18 android16-6.12 f1c9c21d1c2f aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/29 19:47 android16-6.12 f1c9c21d1c2f 6ef5c1e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/26 17:26 android16-6.12 579215f16d4e 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/26 12:11 android16-6.12 579215f16d4e 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/24 00:35 android16-6.12 629d76c0f948 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/22 03:30 android16-6.12 c2f8d5c68db2 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/21 22:45 android16-6.12 c2f8d5c68db2 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/21 21:09 android16-6.12 c2f8d5c68db2 7c5de9c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/21 10:15 android16-6.12 5aeb3ef16d03 7c5de9c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/20 00:55 android16-6.12 0fd55a309793 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/18 12:01 android16-6.12 0fd55a309793 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/16 21:15 android16-6.12 57c0ba8fb2f8 71b49442 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/16 06:00 android16-6.12 c6f9cfff7e53 27a8bd60 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/15 21:11 android16-6.12 a123382dbca7 a4ed0f4f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/15 17:51 android16-6.12 a123382dbca7 a4ed0f4f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/14 17:35 android16-6.12 5dd528d5e93a 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/12 16:19 android16-6.12 0026e4ecedf0 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/11 21:34 android16-6.12 0026e4ecedf0 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/11 19:40 android16-6.12 0026e4ecedf0 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/10 18:38 android16-6.12 0e0925f37543 99e64375 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/10 09:29 android16-6.12 0e0925f37543 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/10 02:58 android16-6.12 0e0925f37543 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/07 17:03 android16-6.12 68c198f6d8bc 76cdc0c0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/07 09:48 android16-6.12 86a5aeeeecfe 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/07 06:24 android16-6.12 86a5aeeeecfe 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/06 04:23 android16-6.12 26ae30f2807e fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/05 08:38 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/05 00:44 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/04 12:21 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/07/04 08:00 android16-6.12 d36feda1de57 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/29 11:19 android16-6.12 cc28ee76a596 6a0c72dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/28 07:59 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/28 00:08 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/26 19:25 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/26 18:05 android16-6.12 220923cf9f76 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/26 13:16 android16-6.12 220923cf9f76 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/24 20:58 android16-6.12 f222c1f727d9 302586aa .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/22 10:55 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/22 06:04 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/21 16:14 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/20 08:45 android16-6.12 8f68185b8289 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/19 07:01 android16-6.12 8f68185b8289 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/18 21:00 android16-6.12 8f68185b8289 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
2026/06/18 19:20 android16-6.12 8f68185b8289 a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnetlink_rcv_msg
* Struck through repros no longer work on HEAD.