MR: 39774
Type: Defect Fix
Disposition: Needs submitting to mipv6
Description:
Fix failure in TAHI conformance test CN-6-4-1 - Processing in upper layer -
Echo Checksum.  It appears the kernel does not perform ICMP checksum if
no error was detected at the link layer.  This patch forces an ICMP checksum
recalculation for MIP6.

diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index f23ebbe..54a77ca 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -663,6 +663,9 @@ static int icmpv6_rcv(struct sk_buff *skb)
 
 	/* Perform checksum. */
 	switch (skb->ip_summed) {
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+	case CHECKSUM_UNNECESSARY:
+#endif
 	case CHECKSUM_COMPLETE:
 		if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
 				     skb->csum))