Re: [syzbot] KASAN: use-after-free Read in io_poll_remove_entries

From: syzbot
Date: Tue Mar 22 2022 - 23:25:19 EST


syzbot has bisected this issue to:

commit 91eac1c69c202d9dad8bf717ae5b92db70bfe5cf
Author: Jens Axboe <axboe@xxxxxxxxx>
Date: Wed Mar 16 22:59:10 2022 +0000

io_uring: cache poll/double-poll state with a request flag

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11819d0b700000
start commit: b47d5a4f6b8d Merge tag 'audit-pr-20220321' of git://git.ke..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=13819d0b700000
console output: https://syzkaller.appspot.com/x/log.txt?x=15819d0b700000
kernel config: https://syzkaller.appspot.com/x/.config?x=c44f0c051803a0ae
dashboard link: https://syzkaller.appspot.com/bug?extid=cd301bb6523ea8cc8ca2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=150525ed700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10d08625700000

Reported-by: syzbot+cd301bb6523ea8cc8ca2@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 91eac1c69c20 ("io_uring: cache poll/double-poll state with a request flag")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection