ipvs: fix sctp chunk length order

Fix wrong but non-fatal access to chunk length.
sch->length should be in network order, next chunk should
be aligned to 4 bytes. Problem noticed in sparse output.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c
index ae8ec6f2768888eec1fb8b8c68b4242eff033525..cd1d7298f7ba779de3e6654b85fafaf7cec58f8e 100644 (file)
--- a/net/netfilter/ipvs/ip_vs_proto_sctp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c
@@ -906,7 +906,7 @@ set_sctp_state(struct ip_vs_proto_data *pd, struct ip_vs_conn *cp,
        sctp_chunkhdr_t _sctpch, *sch;
        unsigned char chunk_type;
        int event, next_state;
-       int ihl;
+       int ihl, cofs;
 
 #ifdef CONFIG_IP_VS_IPV6
        ihl = cp->af == AF_INET ? ip_hdrlen(skb) : sizeof(struct ipv6hdr);
@@ -914,8 +914,8 @@ set_sctp_state(struct ip_vs_proto_data *pd, struct ip_vs_conn *cp,
        ihl = ip_hdrlen(skb);
 #endif
 
-       sch = skb_header_pointer(skb, ihl + sizeof(sctp_sctphdr_t),
-                               sizeof(_sctpch), &_sctpch);
+       cofs = ihl + sizeof(sctp_sctphdr_t);
+       sch = skb_header_pointer(skb, cofs, sizeof(_sctpch), &_sctpch);
        if (sch == NULL)
                return;
 
@@ -933,10 +933,12 @@ set_sctp_state(struct ip_vs_proto_data *pd, struct ip_vs_conn *cp,
         */
        if ((sch->type == SCTP_CID_COOKIE_ECHO) ||
            (sch->type == SCTP_CID_COOKIE_ACK)) {
-               sch = skb_header_pointer(skb, (ihl + sizeof(sctp_sctphdr_t) +
-                               sch->length), sizeof(_sctpch), &_sctpch);
-               if (sch) {
-                       if (sch->type == SCTP_CID_ABORT)
+               int clen = ntohs(sch->length);
+
+               if (clen >= sizeof(sctp_chunkhdr_t)) {
+                       sch = skb_header_pointer(skb, cofs + ALIGN(clen, 4),
+                                                sizeof(_sctpch), &_sctpch);
+                       if (sch && sch->type == SCTP_CID_ABORT)
                                chunk_type = sch->type;
                }
        }