From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pan Bian Subject: [PATCH 1/1] lwtunnel: check return value of nla_nest_start Date: Sun, 23 Apr 2017 14:28:37 +0800 Message-ID: <1492928917-25628-1-git-send-email-bianpan2016@163.com> Cc: David Ahern , Roopa Prabhu , Alexei Starovoitov , David Lebrun , Tom Herbert , Robert Shearman , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian To: "David S. Miller" Return-path: Received: from m50-134.163.com ([123.125.50.134]:41077 "EHLO m50-134.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933481AbdDWG31 (ORCPT ); Sun, 23 Apr 2017 02:29:27 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Function nla_nest_start() may return a NULL pointer on error. However, in function lwtunnel_fill_encap(), the return value of nla_nest_start() is not validated before it is used. This patch checks the return value of nla_nest_start() against NULL. Signed-off-by: Pan Bian --- net/core/lwtunnel.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c index 6df9f8f..3471ce7 100644 --- a/net/core/lwtunnel.c +++ b/net/core/lwtunnel.c @@ -216,6 +216,8 @@ int lwtunnel_fill_encap(struct sk_buff *skb, struct lwtunnel_state *lwtstate) ret = -EOPNOTSUPP; nest = nla_nest_start(skb, RTA_ENCAP); + if (!nest) + goto nla_put_failure; rcu_read_lock(); ops = rcu_dereference(lwtun_encaps[lwtstate->type]); if (likely(ops && ops->fill_encap)) -- 1.9.1