SYZFAIL: tun: read failed (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ced74610217f freebsd-update: Mention upgrading packages, n..
git tree: freebsd-src
console output: https://syzkaller.appspot.com/x/log.txt?x=115bbc1a580000
dashboard link: https://syzkaller.appspot.com/bug?extid=4394c382e90c8b58a3f7

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4394c3...@syzkaller.appspotmail.com

SYZFAIL: tun: read failed
(errno 9: Bad file descriptor)
SYZFAIL: child failed
(errno 0: No error: 0)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: open of /dev/kcov failed
(errno 2: No such file or directory)
SYZFAIL: repeatedly failed to execute the program
proc=1 req=184 state=1 status=67 (errno 9: Bad file descriptor)


FreeBSD/amd64 (ci-freebsd-main-3.us-central1-b.c.syzkaller.internal) (ttyu0)

login: if_delmulti_locked: detaching ifnet instance 0xfffffe006e79f800
if_delmulti_locked: detaching ifnet instance 0xfffffe0007795000
set $lines = 0
Password:
Login incorrect
login: show registers
Password:
Login incorrect
login: ps
Password:
Login incorrect
login: show malloc
Password:
Login incorrect
show all tcpcbs/bl


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