1 files changed, 8 insertions, 26 deletions

diff --git a/net/ipv4/ipcomp.c b/net/ipv4/ipcomp.c
index 95278b22b669..3ed8b57a1002 100644
--- a/net/ipv4/ipcomp.c
+++ b/net/ipv4/ipcomp.c
@@ -45,7 +45,6 @@ static LIST_HEAD(ipcomp_tfms_list);
 static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb)
 {
         int err, plen, dlen;
-        struct iphdr *iph;
         struct ipcomp_data *ipcd = x->data;
         u8 *start, *scratch;
         struct crypto_tfm *tfm;
@@ -74,8 +73,6 @@ static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb)
                 
         skb_put(skb, dlen - plen);
         memcpy(skb->data, scratch, dlen);
-        iph = skb->nh.iph;
-        iph->tot_len = htons(dlen + iph->ihl * 4);
 out:    
         put_cpu();
         return err;
@@ -83,34 +80,21 @@ out:
 
 static int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb)
 {
-        u8 nexthdr;
-        int err = 0;
+        int err = -ENOMEM;
         struct iphdr *iph;
-        union {
-                struct iphdr    iph;
-                char            buf[60];
-        } tmp_iph;
-
+        struct ip_comp_hdr *ipch;
 
-        if ((skb_is_nonlinear(skb) || skb_cloned(skb)) &&
-            skb_linearize(skb, GFP_ATOMIC) != 0) {
-                err = -ENOMEM;
+        if (skb_linearize_cow(skb))
                 goto out;
-        }
 
         skb->ip_summed = CHECKSUM_NONE;
 
         /* Remove ipcomp header and decompress original payload */      
         iph = skb->nh.iph;
-        memcpy(&tmp_iph, iph, iph->ihl * 4);
-        nexthdr = *(u8 *)skb->data;
-        skb_pull(skb, sizeof(struct ip_comp_hdr));
-        skb->nh.raw += sizeof(struct ip_comp_hdr);
-        memcpy(skb->nh.raw, &tmp_iph, tmp_iph.iph.ihl * 4);
-        iph = skb->nh.iph;
-        iph->tot_len = htons(ntohs(iph->tot_len) - sizeof(struct ip_comp_hdr));
-        iph->protocol = nexthdr;
-        skb->h.raw = skb->data;
+        ipch = (void *)skb->data;
+        iph->protocol = ipch->nexthdr;
+        skb->h.raw = skb->nh.raw + sizeof(*ipch);
+        __skb_pull(skb, sizeof(*ipch));
         err = ipcomp_decompress(x, skb);
 
 out:    
@@ -171,10 +155,8 @@ static int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb)
                 goto out_ok;
         }
 
-        if ((skb_is_nonlinear(skb) || skb_cloned(skb)) &&
-            skb_linearize(skb, GFP_ATOMIC) != 0) {
+        if (skb_linearize_cow(skb))
                 goto out_ok;
-        }
         
         err = ipcomp_compress(x, skb);
         iph = skb->nh.iph;