Re: KASAN: use-after-free Read in nbd_genl_connect

From: Josef Bacik
Date: Mon Feb 22 2021 - 13:21:14 EST


On 2/22/21 3:25 AM, syzbot wrote:
Hello,

syzbot found the following issue on:

HEAD commit: f40ddce8 Linux 5.11
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=179e8d22d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=e53d04227c52a0df
dashboard link: https://syzkaller.appspot.com/bug?extid=429d3f82d757c211bff3
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10d190cad00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13dc8a82d00000

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1128ae60d00000
final oops: https://syzkaller.appspot.com/x/report.txt?x=1328ae60d00000
console output: https://syzkaller.appspot.com/x/log.txt?x=1528ae60d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+429d3f82d757c211bff3@xxxxxxxxxxxxxxxxxxxxxxxxx


#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next.git nbd-kasan-fix