Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6

[cascardo/linux.git] / net / dccp / options.c

diff --git a/net/dccp/options.c b/net/dccp/options.c
index 5adeeed..f06ffcf 100644 (file)
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -54,7 +54,6 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
        struct dccp_sock *dp = dccp_sk(sk);
        const struct dccp_hdr *dh = dccp_hdr(skb);
        const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
-       u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
        unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
        unsigned char *opt_ptr = options;
        const unsigned char *opt_end = (unsigned char *)dh +
@@ -129,14 +128,6 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                        if (rc)
                                goto out_featneg_failed;
                        break;
-               case DCCPO_ACK_VECTOR_0:
-               case DCCPO_ACK_VECTOR_1:
-                       if (dccp_packet_without_ack(skb))   /* RFC 4340, 11.4 */
-                               break;
-                       if (dp->dccps_hc_rx_ackvec != NULL &&
-                           dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
-                               goto out_invalid_option;
-                       break;
                case DCCPO_TIMESTAMP:
                        if (len != 4)
                                goto out_invalid_option;
@@ -226,6 +217,16 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
                                                     pkt_type, opt, value, len))
                                goto out_invalid_option;
                        break;
+               case DCCPO_ACK_VECTOR_0:
+               case DCCPO_ACK_VECTOR_1:
+                       if (dccp_packet_without_ack(skb))   /* RFC 4340, 11.4 */
+                               break;
+                       /*
+                        * Ack vectors are processed by the TX CCID if it is
+                        * interested. The RX CCID need not parse Ack Vectors,
+                        * since it is only interested in clearing old state.
+                        * Fall through.
+                        */
                case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC:
                        if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
                                                     pkt_type, opt, value, len))
@@ -429,6 +430,7 @@ static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
 {
        struct dccp_sock *dp = dccp_sk(sk);
        struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
+       struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
        const u16 buflen = dccp_ackvec_buflen(av);
        /* Figure out how many options do we need to represent the ackvec */
        const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
@@ -437,10 +439,25 @@ static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
        const unsigned char *tail, *from;
        unsigned char *to;
 
-       if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+       if (dcb->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
+               DCCP_WARN("Lacking space for %u bytes on %s packet\n", len,
+                         dccp_packet_name(dcb->dccpd_type));
                return -1;
-
-       DCCP_SKB_CB(skb)->dccpd_opt_len += len;
+       }
+       /*
+        * Since Ack Vectors are variable-length, we can not always predict
+        * their size. To catch exception cases where the space is running out
+        * on the skb, a separate Sync is scheduled to carry the Ack Vector.
+        */
+       if (len > DCCPAV_MIN_OPTLEN &&
+           len + dcb->dccpd_opt_len + skb->len > dp->dccps_mss_cache) {
+               DCCP_WARN("No space left for Ack Vector (%u) on skb (%u+%u), "
+                         "MPS=%u ==> reduce payload size?\n", len, skb->len,
+                         dcb->dccpd_opt_len, dp->dccps_mss_cache);
+               dp->dccps_sync_scheduled = 1;
+               return 0;
+       }
+       dcb->dccpd_opt_len += len;
 
        to   = skb_push(skb, len);
        len  = buflen;
@@ -481,7 +498,7 @@ static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
        /*
         * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
         */
-       if (dccp_ackvec_update_records(av, DCCP_SKB_CB(skb)->dccpd_seq, nonce))
+       if (dccp_ackvec_update_records(av, dcb->dccpd_seq, nonce))
                return -ENOBUFS;
        return 0;
 }