Patch "net: pktgen: fix null ptr deref in skb allocation" has been added to the 4.4-stable tree

Patch "net: pktgen: fix null ptr deref in skb allocation" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    net: pktgen: fix null ptr deref in skb allocation

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-pktgen-fix-null-ptr-deref-in-skb-allocation.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Tue Jan 26 21:31:27 PST 2016
From: John Fastabend <john.fastabend@gmail.com>
Date: Sun, 10 Jan 2016 21:38:44 -0800
Subject: net: pktgen: fix null ptr deref in skb allocation

From: John Fastabend <john.fastabend@gmail.com>

[ Upstream commit 3de03596dfeee48bc803c1d1a6daf60a459929f3 ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/core/pktgen.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -2787,7 +2787,9 @@ static struct sk_buff *pktgen_alloc_skb(
 	} 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;
 }


Patches currently in stable-queue which might be from john.fastabend@gmail.com are

queue-4.4/net-pktgen-fix-null-ptr-deref-in-skb-allocation.patch