[SCTP] Multiple causes may be embedded in an ERROR chunk (ardelle.fan)

include/net/sctp/sctp.h

@@ -457,6 +457,18 @@ for (pos.v = chunk->member;\
      pos.v <= (void *)chunk + end - WORD_ROUND(ntohs(pos.p->length)); \
      pos.v += WORD_ROUND(ntohs(pos.p->length)))
 
+#define sctp_walk_errors(err, chunk_hdr)\
+_sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
+
+#define _sctp_walk_errors(err, chunk_hdr, end)\
+for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
+	    sizeof(sctp_chunkhdr_t));\
+     (void *)err <= (void *)chunk_hdr + end - sizeof(sctp_errhdr_t) &&\
+     (void *)err <= (void *)chunk_hdr + end - \
+		    WORD_ROUND(ntohs(err->length));\
+     err = (sctp_errhdr_t *)((void *)err + \
+	    WORD_ROUND(ntohs(err->length))))
+     
 /* Round an int up to the next multiple of 4.  */
 #define WORD_ROUND(s) (((s)+3)&~3)
 

net/sctp/input.c

@@ -503,10 +503,11 @@ int sctp_rcv_ootb(struct sk_buff *skb)
 			goto discard;
 
 		if (SCTP_CID_ERROR == ch->type) {
-			err = (sctp_errhdr_t *)(ch + sizeof(sctp_chunkhdr_t));
+			sctp_walk_errors(err, ch) {
 				if (SCTP_ERROR_STALE_COOKIE == err->cause)
 					goto discard;
 			}
+		}
 
 		ch = (sctp_chunkhdr_t *) ch_end;
 	} while (ch_end < skb->tail);

net/sctp/sm_statefuns.c

@@ -1787,24 +1787,17 @@ sctp_disposition_t sctp_sf_cookie_echoed_err(const struct sctp_endpoint *ep,
 	struct sctp_chunk *chunk = arg;
 	sctp_errhdr_t *err;
 
-	err = (sctp_errhdr_t *)(chunk->skb->data);
-
-	/* If we have gotten too many failures, give up.  */
-	if (1 + asoc->counters[SCTP_COUNTER_INIT_ERROR] >
-					 asoc->max_init_attempts) {
-		/* INIT_FAILED will issue an ulpevent.  */
-		sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED,
-				SCTP_U32(err->cause));
-		return SCTP_DISPOSITION_DELETE_TCB;
-	}
-
 	/* Process the error here */
-	switch (err->cause) {
-	case SCTP_ERROR_STALE_COOKIE:
-		return sctp_sf_do_5_2_6_stale(ep, asoc, type, arg, commands);
-	default:
-		return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
+	/* FUTURE FIXME:  When PR-SCTP related and other optional
+	 * parms are emitted, this will have to change to handle multiple
+	 * errors.
+	 */
+	sctp_walk_errors(err, chunk->chunk_hdr) {
+		if (SCTP_ERROR_STALE_COOKIE == err->cause)
+			return sctp_sf_do_5_2_6_stale(ep, asoc, type, 
+							arg, commands);
 	}
+	return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
 }
 
 /*