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

Status: upstream: reported syz repro on 2025/11/09 04:42
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+78232d2800bd33a10eec@syzkaller.appspotmail.com
First crash: 269d, last: 208d
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/11/10 linux-6.6.y (ToT) 0a805b6ea8cd syz [report] SYZFAIL: tun: can't open /dev/net/tun
2025/11/10 upstream (ToT) e9a6fb0bcdd7 syz Didn't crash
▶ ▼ 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 174d 295d 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 4d11h 270d 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 1732d 1732d 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 100d 999d 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 118d 1619d 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 447d 1808d 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 1618d 1761d 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 89d 999d 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 614d 614d 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 1914d 1914d 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 105d 400d 0/1 premoderation: reported syz repro on 2025/07/01 04:36
linux-6.1 SYZFAIL: tun: can't open /dev/net/tun origin:upstream -1 syz done 1 674d 978d 3/3 fixed on 2024/11/01 17:06
▶ ▼ Fix bisection attempts (4)
Created Duration User Patch Repo Result
2026/04/24 08:59 13m fix candidate upstream error job log
2026/03/25 04:30 1m fix candidate upstream error job log
2026/02/23 04:09 1m fix candidate upstream error job log
2026/01/23 14:54 1m fix candidate upstream error job log

Sample crash report:
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: tun: can't open /dev/net/tun
 (errno 2: No such file or directory)
loop exited with status 67
SYZFAIL: repeatedly failed to execute the program
proc=1 req=2195 state=3 status=67 (errno 32: Broken pipe)
connection error: failed to recv *flatrpc.ExecutorMessageRawT: read tcp 127.0.0.1:45721->127.0.0.1:37344: read: connection reset by peer

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/08 17:53 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf SYZFAIL: tun: can't open /dev/net/tun
2025/12/05 16:12 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf SYZFAIL: tun: can't open /dev/net/tun
2025/11/09 04:42 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf SYZFAIL: tun: can't open /dev/net/tun
2025/12/20 16:52 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf SYZFAIL: tun: can't open /dev/net/tun
2025/12/12 20:33 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan SYZFAIL: tun: can't open /dev/net/tun
* Struck through repros no longer work on HEAD.