Re: [syzbot] [reiserfs?] KASAN: null-ptr-deref Read in fix_nodes

[syzbot]

syzbot has bisected this issue to:

commit d24396c5290ba8ab04ba505176874c4e04a2d53c
Author: Rustam Kovhaev <rkovhaev@xxxxxxxxx>
Date:   Sun Nov 1 14:09:58 2020 +0000

    reiserfs: add check for an invalid ih_entry_count

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15244cfa680000
start commit:   b6dad5178cea Merge tag 'nios2_fix_v6.4' of git://git.kerne..
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=17244cfa680000
console output: https://syzkaller.appspot.com/x/log.txt?x=13244cfa680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ac246111fb601aec
dashboard link: https://syzkaller.appspot.com/bug?extid=5184326923f180b9d11a
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10bbc887280000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15c9558b280000

Reported-by: syzbot+5184326923f180b9d11a@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: d24396c5290b ("reiserfs: add check for an invalid ih_entry_count")

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