vserver 1.9.3

[linux-2.6.git] / net / ipv4 / netfilter / ipt_ECN.c

diff --git a/net/ipv4/netfilter/ipt_ECN.c b/net/ipv4/netfilter/ipt_ECN.c
index 8ca4025..120109c 100644 (file)
--- a/net/ipv4/netfilter/ipt_ECN.c
+++ b/net/ipv4/netfilter/ipt_ECN.c
@@ -52,34 +52,39 @@ set_ect_ip(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
 static inline int
 set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo, int inward)
 {
-       struct tcphdr tcph;
+       struct tcphdr _tcph, *th;
        u_int16_t diffs[2];
 
        /* Not enought header? */
-       if (skb_copy_bits(*pskb, (*pskb)->nh.iph->ihl*4, &tcph, sizeof(tcph))
-           < 0)
+       th = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4,
+                               sizeof(_tcph), &_tcph);
+       if (th == NULL)
                return 0;
 
-       diffs[0] = ((u_int16_t *)&tcph)[6];
+       diffs[0] = ((u_int16_t *)th)[6];
        if (einfo->operation & IPT_ECN_OP_SET_ECE)
-               tcph.ece = einfo->proto.tcp.ece;
+               th->ece = einfo->proto.tcp.ece;
 
        if (einfo->operation & IPT_ECN_OP_SET_CWR)
-               tcph.cwr = einfo->proto.tcp.cwr;
-       diffs[1] = ((u_int16_t *)&tcph)[6];
+               th->cwr = einfo->proto.tcp.cwr;
+       diffs[1] = ((u_int16_t *)&th)[6];
 
        /* Only mangle if it's changed. */
        if (diffs[0] != diffs[1]) {
                diffs[0] = diffs[0] ^ 0xFFFF;
                if (!skb_ip_make_writable(pskb,
-                                         (*pskb)->nh.iph->ihl*4+sizeof(tcph)))
+                                         (*pskb)->nh.iph->ihl*4+sizeof(_tcph)))
                        return 0;
+
+               if (th != &_tcph)
+                       memcpy(&_tcph, th, sizeof(_tcph));
+
                if ((*pskb)->ip_summed != CHECKSUM_HW)
-                       tcph.check = csum_fold(csum_partial((char *)diffs,
-                                              sizeof(diffs),
-                                              tcph.check^0xFFFF));
+                       _tcph.check = csum_fold(csum_partial((char *)diffs,
+                                                            sizeof(diffs),
+                                                            _tcph.check^0xFFFF));
                memcpy((*pskb)->data + (*pskb)->nh.iph->ihl*4,
-                      &tcph, sizeof(tcph));
+                      &_tcph, sizeof(_tcph));
                if ((*pskb)->ip_summed == CHECKSUM_HW)
                        if (skb_checksum_help(pskb, inward))
                                return 0;