From: David Ahern <dsah...@gmail.com>
Date: Wed, 10 Jan 2018 13:00:39 -0800
> syzbot triggered the WARN_ON in netlink_ack testing the bad_attr value.
> The problem is that netlink_rcv_skb loops over the skb repeatedly invoking
> the callback and without resetting the extack leaving potentially stale
> data. Initializing each time through avoids the WARN_ON.
>
> Fixes: 2d4bc93368f5a ("netlink: extended ACK reporting")
> Reported-by: syzbot+315fa6766d0f7c359...@syzkaller.appspotmail.com
> Signed-off-by: David Ahern <dsah...@gmail.com>
Applied and queued up for -stable, thanks David.
