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INFO: task hung in tun_chr_close (5)

Status: upstream: reported C repro on 2024/09/15 19:59
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+b0ae8f1abf7d891e0426@syzkaller.appspotmail.com
First crash: 635d, last: 14h51m
Cause bisection: introduced by (bisect log) :
commit 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22
Author: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Date: Sat Sep 29 00:59:43 2018 +0000

  tc: Add support for configuring the taprio scheduler

Crash: BUG: unable to handle kernel NULL pointer dereference in taprio_dequeue (log)
Repro: syz .config
  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireguard?] INFO: task hung in tun_chr_close (5) 0 (4) 2026/03/31 17:17
▶ ▼ Similar bugs (14)
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 507d 749d 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 2064d 2064d 0/1 auto-closed as invalid on 2020/12/09 18:55
upstream INFO: task hung in tun_chr_close (4) net 1 syz unreliable error 14 1605d 1666d 0/29 auto-closed as invalid on 2022/09/18 21:51
upstream INFO: task hung in tun_chr_close net 1 5 2390d 2972d 0/29 closed as dup on 2018/02/16 08:24
linux-4.19 INFO: task hung in tun_chr_close (3) 1 1 1341d 1341d 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 619d 686d 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 637d 2600d 26/29 fixed on 2024/07/09 19:14
android-49 INFO: task hung in tun_chr_close 1 1 2886d 2886d 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 1147d 1175d 0/1 upstream: reported on 2023/01/18 07:05
linux-4.19 INFO: task hung in tun_chr_close (2) 1 6 1553d 1647d 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 97d 97d 0/3 upstream: reported on 2025/12/30 21:13
upstream INFO: task hung in tun_chr_close (3) net 1 1 1777d 1777d 0/29 auto-closed as invalid on 2021/08/23 13:06
android-44 INFO: task hung in tun_chr_close 1 1 2895d 2895d 0/2 auto-closed as invalid on 2019/02/22 15:23
upstream INFO: task hung in tun_chr_close (2) net 1 7 1886d 2107d 0/29 auto-closed as invalid on 2021/05/17 11:47
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/03/01 18:51 21m retest repro net report log
2026/03/01 18:33 25m retest repro net report log
2026/03/01 18:26 22m retest repro upstream report log
2026/03/01 16:32 20m retest repro upstream report log
2026/03/01 16:32 21m retest repro upstream report log
2026/03/01 16:32 22m retest repro upstream report log
2026/03/01 16:32 20m retest repro upstream report log
2026/03/01 16:32 21m retest repro upstream report log
2025/10/10 16:44 22m retest repro net report log
2025/10/10 02:25 18m retest repro upstream report log

Sample crash report:
INFO: task syz-executor:5978 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22400 pid:5978  tgid:5978  ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
 tun_detach drivers/net/tun.c:634 [inline]
 tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436

Crashes (660):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/31 17:16 net 47ab2c12c87a aeea1c72 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2025/09/04 23:00 upstream 08b06c30a445 d291dd2d .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2025/08/09 04:06 upstream 37816488247d 32a0e5ed .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2025/08/05 18:13 upstream 7e161a991ea7 37880f40 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2025/05/07 12:22 upstream 0d8d44db295c 350f4ffc .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2025/03/08 21:35 upstream 2a520073e74f 7e3bd60d .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2024/11/19 01:31 upstream 9fb2cfa4635a 571351cb .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2024/12/17 17:58 net 7ed2d9158877 c8c15bb2 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2026/03/07 11:42 upstream 651690480a96 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in tun_chr_close
2026/03/04 04:37 upstream 0031c06807cf 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in tun_chr_close
2026/02/14 19:33 upstream 770aaedb461a 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in tun_chr_close
2026/01/26 18:24 upstream 63804fed149a 55756628 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2026/01/21 10:01 upstream 6c790212c588 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2026/01/19 02:10 upstream e84d960149e7 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2026/01/18 02:09 upstream d3eeb99bbc99 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2026/01/17 07:04 upstream 39d3389331ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in tun_chr_close
2026/01/15 11:38 upstream 944aacb68baf d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2026/01/09 14:06 upstream 623fb9912f6a d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2025/12/31 16:23 upstream c8ebd433459b d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in tun_chr_close
2025/12/21 20:25 upstream 9094662f6707 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2025/12/20 07:40 upstream dd9b004b7ff3 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2025/12/05 14:26 upstream 2061f18ad76e d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2025/12/05 08:14 upstream aa833fc394ba d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/12/03 15:10 upstream 3f9f0252130e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in tun_chr_close
2025/11/26 12:37 upstream 30f09200cc4a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/26 00:25 upstream 4ff71af020ae 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/22 12:11 upstream 07e27ad16399 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/20 03:16 upstream cd89d487374c 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/19 12:49 upstream 097a6c336d00 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/18 09:17 upstream 8b789f2b7602 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/17 00:40 upstream 5aca7966d2a7 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/16 04:15 upstream 46a51f4f5eda e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/16 02:24 upstream 46a51f4f5eda e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/15 13:55 upstream f83ec76bf285 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/13 15:54 upstream 22f20375f5b7 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in tun_chr_close
2025/09/12 23:32 upstream 22f20375f5b7 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/06 21:41 upstream b236920731dd d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/04 05:52 upstream b9a10f876409 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/09/01 09:07 upstream b320789d6883 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/08/28 05:19 upstream 39f90c196721 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/08/26 11:20 upstream b6add54ba618 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/08/25 15:58 upstream 1b237f190eb3 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in tun_chr_close
2025/08/25 11:08 upstream 1b237f190eb3 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/08/24 16:57 upstream c330cb607721 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in tun_chr_close
2025/08/18 20:54 upstream c17b750b3ad9 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in tun_chr_close
2025/07/16 07:08 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in tun_chr_close
2024/09/11 19:42 upstream 7c6a3a65ace7 9326a104 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in tun_chr_close
2024/09/01 23:27 upstream c9f016e72b5c 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in tun_chr_close
2026/04/01 09:06 upstream dbf00d8d23b4 fb8b2c26 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in tun_chr_close
2026/02/09 11:10 upstream 05f7e89ab973 df949cd9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in tun_chr_close
2025/11/20 22:48 upstream 8e621c9a3375 280ea308 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in tun_chr_close
2025/03/08 19:03 upstream 2a520073e74f 7e3bd60d .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in tun_chr_close
2026/02/15 16:19 net ee5492fd88cf 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2025/12/25 05:13 net 6402078bd9d1 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2025/12/07 06:43 net 0373d5c387f2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2025/11/19 04:20 net 0f08f0b0fb5e ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2025/09/21 08:35 net b65678cacc03 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2025/09/04 10:20 net c5142df58d5a d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in tun_chr_close
2026/04/06 17:56 net-next 3741f8fa004b 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2026/01/26 16:15 net-next bf2e36c9dab9 a4c52dd6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2026/01/08 11:22 net-next 8e7148b56023 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2026/01/07 01:38 net-next 956f569c90ab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2026/01/03 19:12 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2026/01/01 04:09 net-next dbf8fe85a16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2025/11/24 11:06 net-next e05021a829b8 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2025/11/08 20:41 net-next a0c3aefb08cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2025/10/10 21:15 net-next 18a7e218cfcd ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2025/09/15 18:56 net-next 5b5ba63a54cc e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in tun_chr_close
2025/06/28 06:57 linux-next 2aeda9592360 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in tun_chr_close
2024/10/14 19:39 linux-next 7f773fd61baa 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in tun_chr_close
* Struck through repros no longer work on HEAD.