On Thu, 2018-05-24 at 11:37 +0200, Greg Kroah-Hartman wrote:
> 4.4-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Xin Long <lucien.xin@xxxxxxxxx>
>
> [ Upstream commit 59d8d4434f429b4fa8a346fd889058bda427a837 ]
>
> Now sctp only delays the authentication for the normal cookie-echo
> chunk by setting chunk->auth_chunk in sctp_endpoint_bh_rcv(). But
> for the duplicated one with auth, in sctp_assoc_bh_rcv(), it does
> authentication first based on the old asoc, which will definitely
> fail due to the different auth info in the old asoc.
[...]
> --- a/net/sctp/associola.c
> +++ b/net/sctp/associola.c
> @@ -1000,9 +1000,10 @@ static void sctp_assoc_bh_rcv(struct wor
> struct sctp_endpoint *ep;
> struct sctp_chunk *chunk;
> struct sctp_inq *inqueue;
> - int state;
> sctp_subtype_t subtype;
> + int first_time = 1; /* is this the first time through the loop */
> int error = 0;
> + int state;
>
> /* The association should be held so we should be safe. */
> ep = asoc->ep;
> @@ -1013,6 +1014,30 @@ static void sctp_assoc_bh_rcv(struct wor
> state = asoc->state;
> subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
>
> + /* If the first chunk in the packet is AUTH, do special
> + * processing specified in Section 6.3 of SCTP-AUTH spec
> + */
> + if (first_time && subtype.chunk == SCTP_CID_AUTH) {
> + struct sctp_chunkhdr *next_hdr;
> +
> + next_hdr = sctp_inq_peek(inqueue);
> + if (!next_hdr)
> + goto normal;
> +
> + /* If the next chunk is COOKIE-ECHO, skip the AUTH
> + * chunk while saving a pointer to it so we can do
> + * Authentication later (during cookie-echo
> + * processing).
> + */
> + if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
> + chunk->auth_chunk = skb_clone(chunk->skb,
> + GFP_ATOMIC);
> + chunk->auth = 1;
Doesn't the first_time flag need to be cleared here (and before the
other continue statement in this loop)?
Ben.
> + continue;
> + }
> + }
> +
> +normal:
[...]
--
Ben Hutchings, Software Developer Codethink Ltd
https://www.codethink.co.uk/ Dale House, 35 Dale Street
Manchester, M1 2HF, United Kingdom
