From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: [PATCH] net: pktgen: fix null ptr deref in skb allocation Date: Sun, 10 Jan 2016 21:38:44 -0800 Message-ID: <20160111053844.3695.82965.stgit@john-Precision-Tower-5810> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: bogdan.hamciuc@freescale.com, davem@davemloft.net To: netdev@vger.kernel.org Return-path: Received: from mail-pf0-f182.google.com ([209.85.192.182]:34184 "EHLO mail-pf0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751036AbcAKFi7 (ORCPT ); Mon, 11 Jan 2016 00:38:59 -0500 Received: by mail-pf0-f182.google.com with SMTP id q63so40537631pfb.1 for ; Sun, 10 Jan 2016 21:38:59 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: 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 --- 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 de8d5cc..4da4d51 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; }