SYZFAIL: tun: can't open /dev/net/tun

Status: fixed on 2024/11/01 17:06
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+d9ddbcc6a2f766478ff7@syzkaller.appspotmail.com
Fix commit: d77278196441 devlink: bump the instance index directly when iterating
First crash: 967d, last: 663d
Fix bisection: fixed by (bisect log) :
commit eff23e59b7871eba63de916a3c9f091cae2253a0
Author: Jakub Kicinski <kuba@kernel.org>
Date: Fri Jan 6 06:33:54 2023 +0000

  devlink: bump the instance index directly when iterating

  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/11/30 upstream (ToT) 3b47bc037bd4 syz [report] SYZFAIL: tun: can't open /dev/net/tun
▶ ▼ Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 SYZFAIL: tun: can't open /dev/net/tun (2) origin:lts-only -1 syz error 12 163d 284d 0/3 upstream: reported syz repro on 2025/10/14 07:23
linux-5.15 SYZFAIL: tun: can't open /dev/net/tun (2) origin:lts-only -1 syz error 4 34d 259d 0/3 upstream: reported syz repro on 2025/11/07 16:34
android-5-10 SYZFAIL: tun: can't open /dev/net/tun -1 1 1721d 1721d 0/2 auto-closed as invalid on 2022/02/05 06:28
android-5-15 SYZFAIL: tun: can't open /dev/net/tun origin:upstream -1 syz error 37 89d 988d 0/2 premoderation: reported syz repro on 2023/11/10 07:03
android-5-10 SYZFAIL: tun: can't open /dev/net/tun (2) -1 syz error error 82 107d 1608d 0/2 premoderation: reported syz repro on 2022/02/27 16:56
android-54 SYZFAIL: tun: can't open /dev/net/tun -1 syz 18 436d 1797d 0/2 upstream: reported syz repro on 2021/08/23 10:35
linux-4.19 SYZFAIL: tun: can't open /dev/net/tun -1 syz error 3 1607d 1750d 0/1 upstream: reported syz repro on 2021/10/09 05:44
android-6-1 SYZFAIL: tun: can't open /dev/net/tun origin:upstream -1 syz error error 39 78d 988d 0/2 premoderation: reported syz repro on 2023/11/09 20:06
linux-5.15 SYZFAIL: tun: can't open /dev/net/tun -1 1 603d 603d 0/3 auto-obsoleted due to no activity on 2025/03/08 18:06
upstream SYZFAIL: tun: can't open /dev/net/tun -1 1 1903d 1903d 0/29 auto-closed as invalid on 2021/08/06 17:44
android-6-12 SYZFAIL: tun: can't open /dev/net/tun origin:upstream -1 syz 54 95d 389d 0/1 premoderation: reported syz repro on 2025/07/01 04:36
linux-6.6 SYZFAIL: tun: can't open /dev/net/tun origin:lts-only -1 syz error 5 197d 258d 0/2 upstream: reported syz repro on 2025/11/09 04:42
▶ ▼ Fix bisection attempts (8)
Created Duration User Patch Repo Result
2024/11/01 11:08 5h06m bisect fix linux-6.1.y OK (1) job log
2024/09/29 20:34 1h40m bisect fix linux-6.1.y OK (0) job log log
2024/08/16 12:27 2h16m bisect fix linux-6.1.y OK (0) job log log
2024/06/13 23:45 1h28m bisect fix linux-6.1.y OK (0) job log log
2024/05/10 05:12 1h27m bisect fix linux-6.1.y OK (0) job log log
2024/03/13 06:22 1h41m bisect fix linux-6.1.y OK (0) job log log
2024/02/11 06:44 1h34m bisect fix linux-6.1.y OK (0) job log log
2023/12/30 22:38 1h38m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
2023/11/30 16:54:02 [FATAL] executor failed 11 times: executor 5: failed to write control pipe: write |1: broken pipe
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/30 17:11 linux-6.1.y 6ac30d748bb0 f819d6f7 .config console log report syz ci2-linux-6-1-kasan-perf SYZFAIL: tun: can't open /dev/net/tun
* Struck through repros no longer work on HEAD.