INFO: task hung in tun_chr_close

Status: upstream: reported C repro on 2026/05/09 00:17
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+9e8fe9504d557db8a499@syzkaller.appspotmail.com
First crash: 85d, last: 85d
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2026/05/25 linux-6.6.y (ToT) 0a40c6fbd105 C [report] INFO: task hung in corrupted
2026/05/25 upstream (ToT) e7ae89a0c97c C Didn't crash
▶ ▼ 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 624d 866d 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 2181d 2181d 0/1 auto-closed as invalid on 2020/12/09 18:55
upstream INFO: task hung in tun_chr_close (5) net prio:high 1 syz, C done 692 1d03h 685d 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 1722d 1783d 0/29 auto-closed as invalid on 2022/09/18 21:51
upstream INFO: task hung in tun_chr_close net 1 5 2507d 3088d 0/29 closed as dup on 2018/02/16 08:24
linux-4.19 INFO: task hung in tun_chr_close (3) 1 1 1458d 1458d 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 736d 803d 0/3 auto-obsoleted due to no activity on 2024/10/04 23:47
upstream INFO: task hung in rtnetlink_rcv_msg net 1 syz, C inconclusive inconclusive 1970 754d 2717d 26/29 fixed on 2024/07/09 19:14
android-49 INFO: task hung in tun_chr_close 1 1 3003d 3003d 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 1264d 1291d 0/1 upstream: reported on 2023/01/18 07:05
linux-4.19 INFO: task hung in tun_chr_close (2) 1 6 1670d 1764d 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 214d 214d 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 1894d 1894d 0/29 auto-closed as invalid on 2021/08/23 13:06
android-44 INFO: task hung in tun_chr_close 1 1 3012d 3012d 0/2 auto-closed as invalid on 2019/02/22 15:23
upstream INFO: task hung in tun_chr_close (2) net 1 7 2003d 2224d 0/29 auto-closed as invalid on 2021/05/17 11:47
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2026/05/31 16:24 15m fix candidate upstream error job log

Sample crash report:
INFO: task syz.0.19:5950 blocked for more than 142 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.19        state:D stack:25552 pid:5950  ppid:5904   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747
 tun_detach drivers/net/tun.c:698 [inline]
 tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511
 __fput+0x234/0x970 fs/file_table.c:384
 task_work_run+0x1d4/0x260 kernel/task_work.c:245

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/09 00:16 linux-6.6.y 3b9f64db0496 b2988c17 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in tun_chr_close
* Struck through repros no longer work on HEAD.