Re: KASAN: slab-out-of-bounds Read in bitmap_ipmac_destroy

syzbot has bisected this bug to:

commit b9a1e627405d68d475a3c1f35e685ccfb5bbe668
Author: Cong Wang [off-list ref]
Date:   Thu Jul 4 00:21:13 2019 +0000

    hsr: implement dellink to clean up resources

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=123fce01e00000
start commit:   4703d911 Merge tag 'xarray-5.5' of git://git.infradead.org..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=113fce01e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=163fce01e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=83c00afca9cf5153
dashboard link: https://syzkaller.appspot.com/bug?extid=a85062dec5d65617cc1c
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1301ed85e00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14b7b79ee00000

Reported-by: syzbot+a85062dec5d65617cc1c@syzkaller.appspotmail.com
Fixes: b9a1e627405d ("hsr: implement dellink to clean up resources")

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