[v5.15] SYZFAIL: tun: ioctl(TUNSETIFF) failed (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 29e53a5b1c4f Linux 5.15.194
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13ae5892580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=bf254572594376912105
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8cd4e3ff852c/disk-29e53a5b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/21e1f773622c/vmlinux-29e53a5b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8f418c0a25cc/bzImage-29e53a5b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bf2545...@syzkaller.appspotmail.com

SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: tun: ioctl(TUNSETIFF) failed
(errno 25: Inappropriate ioctl for device)
loop exited with status 67
SYZFAIL: repeatedly failed to execute the program
proc=6 req=2657 state=3 status=67 (errno 9: Bad file descriptor)


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