Re: [PATCH net 2/3] sctp: return back transport in __sctp_rcv_init_lookup

On Sat, Oct 29, 2016 at 5:39 AM, Marcelo Ricardo Leitner
[off-list ref] wrote:

On Fri, Oct 28, 2016 at 05:42:21PM -0200, Marcelo Ricardo Leitner wrote:

quoted

On Fri, Oct 28, 2016 at 06:10:53PM +0800, Xin Long wrote:

quoted

Prior to this patch, it used a local variable to save the transport that is
looked up by __sctp_lookup_association(), and didn't return it back. But in
sctp_rcv, it is used to initialize chunk->transport. So when hitting this
code, it was initializing chunk->transport with some random stack value
instead.

here should be:
So when hitting this, even if it found the transport, it was still initializing
chunk->transport with null instead.

quoted

quoted

This patch is to return the transport back through transport pointer
that is from __sctp_rcv_lookup_harder().

Signed-off-by: Xin Long <lucien.xin@gmail.com>

Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>

transport pointer in sctp_rcv() is initialized to null and there are
checks for it after this path, so this shouldn't be exploitable, just
malfunction.

This actually sort of contradicts the changelog.

Xin, did I miss something here? Seems we need to update the changelog if
not.

You're right, thanks, will repost.