Re: KASAN: use-after-free Write in vcs_read

[syzbot]

syzbot has bisected this issue to:

commit b1c32fcfadf5593ab7a63261cc8a5747c36e627e
Author: Jiri Slaby <jslaby@xxxxxxx>
Date:   Tue Aug 18 08:57:05 2020 +0000

    vc_screen: extract vcs_read_buf_header

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=13259dee900000
start commit:   494d311a Add linux-next specific files for 20200821
git tree:       linux-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=10a59dee900000
console output: https://syzkaller.appspot.com/x/log.txt?x=17259dee900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a61d44f28687f508
dashboard link: https://syzkaller.appspot.com/bug?extid=ad1f53726c3bd11180cb
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16704b7e900000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1588a046900000

Reported-by: syzbot+ad1f53726c3bd11180cb@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: b1c32fcfadf5 ("vc_screen: extract vcs_read_buf_header")

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