sctp: delay as much as possible skb_linearize

[cascardo/linux.git] / net / sctp / inqueue.c

diff --git a/net/sctp/inqueue.c b/net/sctp/inqueue.c
index 9d87bba..5ba08ce 100644 (file)
--- a/net/sctp/inqueue.c
+++ b/net/sctp/inqueue.c
@@ -130,7 +130,8 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
         * at this time.
         */
 
-       if ((chunk = queue->in_progress)) {
+       chunk = queue->in_progress;
+       if (chunk) {
                /* There is a packet that we have been working on.
                 * Any post processing work to do before we move on?
                 */
@@ -152,15 +153,29 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
        if (!chunk) {
                struct list_head *entry;
 
+next_chunk:
                /* Is the queue empty?  */
                if (list_empty(&queue->in_chunk_list))
                        return NULL;
 
                entry = queue->in_chunk_list.next;
-               chunk = queue->in_progress =
-                       list_entry(entry, struct sctp_chunk, list);
+               chunk = list_entry(entry, struct sctp_chunk, list);
                list_del_init(entry);
 
+               /* Linearize if it's not GSO */
+               if (skb_is_nonlinear(chunk->skb)) {
+                       if (skb_linearize(chunk->skb)) {
+                               __SCTP_INC_STATS(dev_net(chunk->skb->dev), SCTP_MIB_IN_PKT_DISCARDS);
+                               sctp_chunk_free(chunk);
+                               goto next_chunk;
+                       }
+
+                       /* Update sctp_hdr as it probably changed */
+                       chunk->sctp_hdr = sctp_hdr(chunk->skb);
+               }
+
+               queue->in_progress = chunk;
+
                /* This is the first chunk in the packet.  */
                chunk->singleton = 1;
                ch = (sctp_chunkhdr_t *) chunk->skb->data;
@@ -172,14 +187,6 @@ struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
 
        chunk->chunk_hdr = ch;
        chunk->chunk_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
-       /* In the unlikely case of an IP reassembly, the skb could be
-        * non-linear. If so, update chunk_end so that it doesn't go past
-        * the skb->tail.
-        */
-       if (unlikely(skb_is_nonlinear(chunk->skb))) {
-               if (chunk->chunk_end > skb_tail_pointer(chunk->skb))
-                       chunk->chunk_end = skb_tail_pointer(chunk->skb);
-       }
        skb_pull(chunk->skb, sizeof(sctp_chunkhdr_t));
        chunk->subh.v = NULL; /* Subheader is no longer valid.  */