SYZFAIL: tun: can't open device

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c02a2875 Fix build after 2c7dc6bae9fd.
git tree: https://github.com/freebsd/freebsd-src.git main
console output: https://syzkaller.appspot.com/x/log.txt?x=1213d182d00000
dashboard link: https://syzkaller.appspot.com/bug?extid=f0015aa9dc06ca0616f5
userspace arch: i386

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+f0015a...@syzkaller.appspotmail.com

SYZFAIL: tun: can't open device


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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 40f41ece tcp: improve handling of SYN segments in SYN-SENT..

git tree: https://github.com/freebsd/freebsd-src.git main

console output: https://syzkaller.appspot.com/x/log.txt?x=147e8edcd00000
dashboard link: https://syzkaller.appspot.com/bug?extid=f0015aa9dc06ca0616f5
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=128d7ef6d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0015a...@syzkaller.appspotmail.com

SYZFAIL: tun: can't open device

device=/dev/tap0 (errno 16: Device busy)

login:

FreeBSD/amd64 (ci-freebsd-main-7.c.syzkaller.internal) (ttyu0)

login: if_delmulti_locked: detaching ifnet instance 0xfffff80004e29000
if_delmulti_locked: detaching ifnet instance 0xfffff80004e24000
Mar 23 05:07:26 ci-freebsd-main-7 dhclient[10886]: Interface tap1 is down, dhclient exiting
if_delmulti_locked: detaching ifnet instance 0xfffff80004e29000
if_delmulti_locked: detaching ifnet instance 0xfffff80004e29000
if_delmulti_locked: detaching ifnet instance 0xfffff80004e24000
if_delmulti_locked: detaching ifnet instance 0xfffff80004e24000
Mar 23 05:07:26 ci-freebsd-main-7 dhclient[10886]: connection closed
if_delmulti_locked: detaching ifnet instance 0xfffff80004e29800
if_delmulti_locked: detaching ifnet instance 0xfffff80004e29800
if_delmulti_locked: detaching ifnet instance 0xfffff80004e29800
Mar 23 05:07:26 ci-freebsd-main-7 dhclient[10886]: exiting.
Ma