caif: Do not dereference NULL in chnl_recv_cb()

In net/caif/chnl_net.c::chnl_recv_cb() we call skb_header_pointer() which may return NULL, but we do not check for a NULL pointer before dereferencing it. This patch adds such a NULL check and properly free's allocated memory and return an error (-EINVAL) on failure - much better than crashing.. Signed-off-by: Jesper Juhl <[email protected]> Acked-by: Sjur Brændeland <[email protected]> Signed-off-by: David S. Miller <[email protected]>
XGWang0 · Aug 20, 2012 · d92c7f8 · d92c7f8
1 parent 6c71bec
commit d92c7f8
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
@@ -94,6 +94,10 @@ static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
 
 	/* check the version of IP */
 	ip_version = skb_header_pointer(skb, 0, 1, &buf);
+	if (!ip_version) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
 
 	switch (*ip_version >> 4) {
 	case 4: