net: Add additional IP fragmentation check

Ignore IP packets which have the "more fragments" flag bit
set.  This flag indicates the IP packet is fragmented and
must be ignored by U-Boot.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

net/net.c

@@ -1399,7 +1399,8 @@ NetReceive(volatile uchar * inpkt, int len)
 		if ((ip->ip_hl_v & 0xf0) != 0x40) {
 			return;
 		}
-		if (ip->ip_off & htons(IP_OFFS)) { /* Can't deal w/ fragments */
+		/* Can't deal with fragments */
+		if (ip->ip_off & htons(IP_OFFS | IP_FLAGS_MFRAG)) {
 			return;
 		}
 		/* can't deal with headers > 20 bytes */