KASAN: use-after-free Write in __sco_sock_close

[syzbot]

syzbot has bisected this issue to:

commit 43ea43b9d8b27b7acd443ec59319faa3cdb8a616
Author: Mauro Carvalho Chehab <mchehab at s-opensource.com>
Date:   Wed Oct 12 11:21:43 2016 +0000

    [media] radio-bcm2048: don't ignore errors

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1036e6a4900000
start commit:   ac3a0c84 Merge git://git.kernel.org/pub/scm/linux/kernel/g..
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=1236e6a4900000
console output: https://syzkaller.appspot.com/x/log.txt?x=1436e6a4900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e59ee776d5aa8d55
dashboard link: https://syzkaller.appspot.com/bug?extid=077eca30d3cb7c02b273
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12cf1904900000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10d52e14900000

Reported-by: syzbot+077eca30d3cb7c02b273 at syzkaller.appspotmail.com
Fixes: 43ea43b9d8b2 ("[media] radio-bcm2048: don't ignore errors")

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