Subject: Re: KASAN: use-after-free Read in bitmap_ipmac_ext_cleanup

From: syzbot <[email-masked]>
Date: Mon, 20 Jan 2020 15:16:00 -0800

syzbot has bisected this bug to:

commit ff95bf28c23490584b9d75913a520bb7bb1f2ecb
Author: Po-Hsu Lin <[email-masked]>
Date:   Mon Jul 1 04:40:31 2019 +0000

    selftests/net: skip psock_tpacket test if KALLSYMS was not enabled

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=17e2e966e00000
start commit:   8f8972a3 Merge tag 'mtd/fixes-for-5.5-rc7' of git://git.ke..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=1412e966e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=1012e966e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d9290aeb7e6cf1c4
dashboard link: https://syzkaller.appspot.com/bug?extid=33fc3ad6fa11675e1a7e
userspace arch: i386
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15982cc9e00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11be38d6e00000

Reported-by: [email-masked]
Fixes: ff95bf28c234 ("selftests/net: skip psock_tpacket test if KALLSYMS was not enabled")

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