macvlan: handle fragmented multicast frames
Fragmented multicast frames are delivered to a single macvlan port,
because ip defrag logic considers other samples are redundant.
Implement a defrag step before trying to send the multicast frame.
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 0e0ab98..763589a 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -682,6 +682,42 @@
}
EXPORT_SYMBOL(ip_defrag);
+struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user)
+{
+ const struct iphdr *iph;
+ u32 len;
+
+ if (skb->protocol != htons(ETH_P_IP))
+ return skb;
+
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ return skb;
+
+ iph = ip_hdr(skb);
+ if (iph->ihl < 5 || iph->version != 4)
+ return skb;
+ if (!pskb_may_pull(skb, iph->ihl*4))
+ return skb;
+ iph = ip_hdr(skb);
+ len = ntohs(iph->tot_len);
+ if (skb->len < len || len < (iph->ihl * 4))
+ return skb;
+
+ if (ip_is_fragment(ip_hdr(skb))) {
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (skb) {
+ if (pskb_trim_rcsum(skb, len))
+ return skb;
+ memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
+ if (ip_defrag(skb, user))
+ return NULL;
+ skb->rxhash = 0;
+ }
+ }
+ return skb;
+}
+EXPORT_SYMBOL(ip_check_defrag);
+
#ifdef CONFIG_SYSCTL
static int zero;