IP_GRE: Fix IP-Identification.
GRE-GSO generates ip fragments with id 0,2,3,4... for every
GSO packet, which is not correct. Following patch fixes it
by setting ip-header id unique id of fragments are allowed.
As Eric Dumazet suggested it is optimized by using inner ip-header
whenever inner packet is ipv4.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ipip.h b/include/net/ipip.h
index 21947cf..fd19625 100644
--- a/include/net/ipip.h
+++ b/include/net/ipip.h
@@ -71,4 +71,21 @@
}
}
+static inline void tunnel_ip_select_ident(struct sk_buff *skb,
+ const struct iphdr *old_iph,
+ struct dst_entry *dst)
+{
+ struct iphdr *iph = ip_hdr(skb);
+
+ if (iph->frag_off & htons(IP_DF))
+ iph->id = 0;
+ else {
+ /* Use inner packet iph-id if possible. */
+ if (skb->protocol == htons(ETH_P_IP) && old_iph->id)
+ iph->id = old_iph->id;
+ else
+ __ip_select_ident(iph, dst,
+ (skb_shinfo(skb)->gso_segs ?: 1) - 1);
+ }
+}
#endif