ipv6: Add fragment reporting to ipv6_skip_exthdr().

While parsing through IPv6 extension headers, fragment headers are
skipped making them invisible to the caller.  This reports the
fragment offset of the last header in order to make it possible to
determine whether the packet is fragmented and, if so whether it is
a first or last fragment.

Signed-off-by: Jesse Gross <jesse@nicira.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 9e2bdccf9143..01d46bff63c3 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -135,11 +135,12 @@ static int is_ineligible(struct sk_buff *skb)
         int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
         int len = skb->len - ptr;
         __u8 nexthdr = ipv6_hdr(skb)->nexthdr;
+        __be16 frag_off;
 
         if (len < 0)
                 return 1;
 
-        ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr);
+        ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr, &frag_off);
         if (ptr < 0)
                 return 0;
         if (nexthdr == IPPROTO_ICMPV6) {
@@ -596,6 +597,7 @@ static void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
         int inner_offset;
         int hash;
         u8 nexthdr;
+        __be16 frag_off;
 
         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
                 return;
@@ -603,7 +605,8 @@ static void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
         nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
         if (ipv6_ext_hdr(nexthdr)) {
                 /* now skip over extension headers */
-                inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
+                inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
+                                                &nexthdr, &frag_off);
                 if (inner_offset<0)
                         return;
         } else {