Forwarded: Re: [syzbot] [fs?] UBSAN: shift-out-of-bounds in befs_check_sb

syzbot
2025-09-28T19:16:52Z

For archival purposes, forwarding an incoming command email to
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com.

***

Subject: Re: [syzbot] [fs?] UBSAN: shift-out-of-bounds in befs_check_sb
Author: xandfury@gmail.com

syzbot <syzbot+fc26c366038b54261e53@syzkaller.appspotmail.com> writes:

> syzbot suspects this issue was fixed by commit:
>
> commit 6f861765464f43a71462d52026fbddfc858239a5
> Author: Jan Kara <jack@suse.cz>
> Date: Wed Nov 1 17:43:10 2023 +0000
>
> fs: Block writes to mounted block devices
>
> bisection log: <https://syzkaller.appspot.com/x/bisect.txt?x=14b5e754180000>
> start commit: 8689f4f2ea56 Merge tag ’mmc-v6.5-2’ of git://git.kernel.or..
> git tree: upstream
> kernel config: <https://syzkaller.appspot.com/x/.config?x=15873d91ff37a949>
> dashboard link: <https://syzkaller.appspot.com/bug?extid=fc26c366038b54261e53>
> syz repro: <https://syzkaller.appspot.com/x/repro.syz?x=14237dc2a80000>
> C reproducer: <https://syzkaller.appspot.com/x/repro.c?x=13e34d22a80000>
>
> If the result looks correct, please mark the issue as fixed by replying with:
>
> #syz fix: fs: Block writes to mounted block devices
>
> For information about bisection process see: <https://goo.gl/tpsmEJ#bisection>

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 6f861765464f43a71462d52026fbddfc858239a5