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

syzbot has bisected this bug to:

commit e9db4ef6bf4ca9894bb324c76e01b8f1a16b2650
Author: John Fastabend [off-list ref]
Date:   Sat Jun 30 13:17:47 2018 +0000

     bpf: sockhash fix omitted bucket lock in sock_close

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1555b795a00000
start commit:   abf02e29 Merge tag 'pm-5.2-rc6' of git://git.kernel.org/pu..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=1755b795a00000
console output: https://syzkaller.appspot.com/x/log.txt?x=1355b795a00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=28ec3437a5394ee0
dashboard link: https://syzkaller.appspot.com/bug?extid=55c548ad445cef6063ab
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=128ce13aa00000

Reported-by: syzbot+55c548ad445cef6063ab@syzkaller.appspotmail.com
Fixes: e9db4ef6bf4c ("bpf: sockhash fix omitted bucket lock in sock_close")

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