[PATCH 22/29] ipvs: get sctphdr by sctphoff in sctp_csum_check

[Pablo Neira Ayuso]

From: Xin Long <lucien....@gmail.com>

sctp_csum_check() is called by sctp_s/dnat_handler() where it calls
skb_make_writable() to ensure sctphdr to be linearized.

So there's no need to get sctphdr by calling skb_header_pointer()
in sctp_csum_check().

Signed-off-by: Xin Long <lucien....@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leit...@gmail.com>
Acked-by: Julian Anastasov <j...@ssi.bg>
Acked-by: Simon Horman <ho...@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org>
---
 net/netfilter/ipvs/ip_vs_proto_sctp.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c 
b/net/netfilter/ipvs/ip_vs_proto_sctp.c
index bc3d1625ecc8..b58ddb7dffd1 100644
--- a/net/netfilter/ipvs/ip_vs_proto_sctp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c
@@ -186,7 +186,7 @@ static int
 sctp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp)
 {
        unsigned int sctphoff;
-       struct sctphdr *sh, _sctph;
+       struct sctphdr *sh;
        __le32 cmp, val;
 
 #ifdef CONFIG_IP_VS_IPV6
@@ -196,10 +196,7 @@ sctp_csum_check(int af, struct sk_buff *skb, struct 
ip_vs_protocol *pp)
 #endif
                sctphoff = ip_hdrlen(skb);
 
-       sh = skb_header_pointer(skb, sctphoff, sizeof(_sctph), &_sctph);
-       if (sh == NULL)
-               return 0;
-
+       sh = (struct sctphdr *)(skb->data + sctphoff);
        cmp = sh->checksum;
        val = sctp_compute_cksum(skb, sctphoff);
 
-- 
2.11.0