syzbot

 sign-in | mailing list | source | docs | 🏰
🐞 Open [1336]
≡ Subsystems
🐞 Fixed [7120]
🐞 Invalid [18809]
⬇ Missing Backports [220]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
✨ AI
💬 Send us feedback

INFO: task hung in tun_chr_close (2)

Status: auto-closed as invalid on 2021/05/17 11:47
Subsystems: net
[Documentation on labels]
First crash: 2158d, last: 1936d
▶ ▼ Similar bugs (15)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in tun_chr_close 1 40 557d 800d 0/3 auto-obsoleted due to no activity on 2025/02/09 21:18
linux-4.19 INFO: task hung in tun_chr_close 1 1 2114d 2114d 0/1 auto-closed as invalid on 2020/12/09 18:55
linux-6.6 INFO: task hung in tun_chr_close origin:lts-only 1 C 1 18d 18d 0/2 upstream: reported C repro on 2026/05/09 00:17
upstream INFO: task hung in tun_chr_close (5) net 1 C done 671 6d22h 618d 0/29 upstream: reported C repro on 2024/09/15 19:59
upstream INFO: task hung in tun_chr_close (4) net 1 syz unreliable error 14 1656d 1716d 0/29 auto-closed as invalid on 2022/09/18 21:51
upstream INFO: task hung in tun_chr_close net 1 5 2440d 3022d 0/29 closed as dup on 2018/02/16 08:24
linux-4.19 INFO: task hung in tun_chr_close (3) 1 1 1391d 1391d 0/1 auto-obsoleted due to no activity on 2022/12/03 04:48
linux-6.1 INFO: task hung in tun_chr_close 1 31 669d 736d 0/3 auto-obsoleted due to no activity on 2024/10/04 23:47
upstream INFO: task hung in rtnetlink_rcv_msg net 1 C inconclusive inconclusive 1970 687d 2651d 26/29 fixed on 2024/07/09 19:14
android-49 INFO: task hung in tun_chr_close 1 1 2936d 2936d 0/3 auto-closed as invalid on 2019/02/22 14:33
linux-4.19 INFO: task hung in tun_chr_close (4) 1 3 1197d 1225d 0/1 upstream: reported on 2023/01/18 07:05
linux-4.19 INFO: task hung in tun_chr_close (2) 1 6 1604d 1698d 0/1 auto-closed as invalid on 2022/05/04 09:03
linux-6.1 INFO: task hung in tun_chr_close (2) 1 1 147d 147d 0/3 auto-obsoleted due to no activity on 2026/04/09 21:13
upstream INFO: task hung in tun_chr_close (3) net 1 1 1828d 1828d 0/29 auto-closed as invalid on 2021/08/23 13:06
android-44 INFO: task hung in tun_chr_close 1 1 2946d 2946d 0/2 auto-closed as invalid on 2019/02/22 15:23

Sample crash report:
INFO: task syz-executor.0:16228 blocked for more than 146 seconds.
      Not tainted 5.11.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:27304 pid:16228 ppid:  8448 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5216
 __mutex_lock_common kernel/locking/mutex.c:1033 [inline]
 __mutex_lock+0x81a/0x1110 kernel/locking/mutex.c:1103
 tun_detach drivers/net/tun.c:676 [inline]
 tun_chr_close+0x3a/0x180 drivers/net/tun.c:3354
 __fput+0x283/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x190 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xc5c/0x2ae0 kernel/exit.c:825
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x427/0x20f0 kernel/signal.c:2773
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b09
RSP: 002b:00007fac4732b218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 0000000000465b09
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/06 01:03 upstream dd86e7fa07a3 23a562df .config console log report info ci-upstream-kasan-gce-root INFO: task hung in tun_chr_close
2021/01/26 17:28 upstream 13391c60da33 55a7d4df .config console log report info ci-upstream-kasan-gce-root INFO: task hung in tun_chr_close
2020/12/13 20:22 upstream 6bff9bb8a292 b22a7ec3 .config console log report info ci-upstream-kasan-gce-root
2020/06/29 15:34 upstream 4e99b32169e8 a2cdad9d .config console log report ci-upstream-kasan-gce-selinux-root
2020/07/06 12:34 upstream 7cc2a8ea1048 51095195 .config console log report ci-upstream-kasan-gce-386
2020/09/27 01:32 net-old 059432495e20 2d5ea0cb .config console log report info ci-upstream-net-this-kasan-gce
2020/08/21 20:07 net-old f6db90964162 6436ce4b .config console log report ci-upstream-net-this-kasan-gce
* Struck through repros no longer work on HEAD.