[Feature][ZXW-65]merged P49 base code

Change-Id: I3e09c0c3d47483bc645f02310380ecb7fc6f4041
diff --git a/ap/os/linux/linux-3.4.x/net/ipv4/ping.c b/ap/os/linux/linux-3.4.x/net/ipv4/ping.c
index 9f471c3..5ff3ed1 100644
--- a/ap/os/linux/linux-3.4.x/net/ipv4/ping.c
+++ b/ap/os/linux/linux-3.4.x/net/ipv4/ping.c
@@ -665,11 +665,13 @@
 	if (msg->msg_name) {
 		struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
 
-		sin->sin_family = AF_INET;
-		sin->sin_port = 0 /* skb->h.uh->source */;
-		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
-		memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
-		*addr_len = sizeof(*sin);
+		if (sin) { //CVE-2013-6432
+			sin->sin_family = AF_INET;
+			sin->sin_port = 0 /* skb->h.uh->source */;
+			sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
+			memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
+			*addr_len = sizeof(*sin);
+		}
 	}
 	if (isk->cmsg_flags)
 		ip_cmsg_recv(msg, skb);