From 3de03596dfeee48bc803c1d1a6daf60a459929f3 Mon Sep 17 00:00:00 2001
From: John Fastabend <john.fastabend@gmail.com>
Date: Sun, 10 Jan 2016 21:38:44 -0800
Subject: [PATCH] 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: 879c7220e82 ("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>
---
net/core/pktgen.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index de8d5cc5eb240..4da4d51a2ccfd 100644
--- 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;
}