Re: [PATCH] net/x25: fix nonblocking connect

From: David Miller
Date: Thu Jan 09 2020 - 21:40:11 EST


From: Martin Schiller <ms@xxxxxxxxxx>
Date: Thu, 9 Jan 2020 07:31:14 +0100

> This patch fixes 2 issues in x25_connect():
>
> 1. It makes absolutely no sense to reset the neighbour and the
> connection state after a (successful) nonblocking call of x25_connect.
> This prevents any connection from being established, since the response
> (call accept) cannot be processed.
>
> 2. Any further calls to x25_connect() while a call is pending should
> simply return, instead of creating new Call Request (on different
> logical channels).
>
> This patch should also fix the "KASAN: null-ptr-deref Write in
> x25_connect" and "BUG: unable to handle kernel NULL pointer dereference
> in x25_connect" bugs reported by syzbot.
>
> Signed-off-by: Martin Schiller <ms@xxxxxxxxxx>
> Reported-by: syzbot+429c200ffc8772bfe070@xxxxxxxxxxxxxxxxxxxxxxxxx
> Reported-by: syzbot+eec0c87f31a7c3b66f7b@xxxxxxxxxxxxxxxxxxxxxxxxx

Applied and queued up for -stable, thanks.