net: pktgen: fix null ptr deref in skb allocation

Fix possible null pointer dereference that may occur when calling skb_reserve() on a null skb. Fixes: 879c722 ("net: pktgen: Observe needed_headroom of the device") Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
mariux64 · Jan 11, 2016 · 3de0359 · 3de0359
1 parent 366f293
commit 3de0359
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
@@ -2787,7 +2787,9 @@ static struct sk_buff *pktgen_alloc_skb(struct net_device *dev,
 	} else {
 		 skb = __netdev_alloc_skb(dev, size, GFP_NOWAIT);
 	}
-	skb_reserve(skb, LL_RESERVED_SPACE(dev));
+
+	if (likely(skb))
+		skb_reserve(skb, LL_RESERVED_SPACE(dev));
 
 	return skb;
 }