From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Aring Subject: [PATCHv2 net 3/3] net: sched: ife: check on metadata length Date: Thu, 19 Apr 2018 17:44:38 -0400 Message-ID: <20180419214438.6801-4-aring@mojatatu.com> References: <20180419214438.6801-1-aring@mojatatu.com> Cc: jhs@mojatatu.com, davem@davemloft.net, xiyou.wangcong@gmail.com, jiri@resnulli.us, yuvalm@mellanox.com, netdev@vger.kernel.org, kernel@mojatatu.com, Alexander Aring To: yotam.gi@gmail.com Return-path: Received: from mail-it0-f67.google.com ([209.85.214.67]:34335 "EHLO mail-it0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753531AbeDSVpS (ORCPT ); Thu, 19 Apr 2018 17:45:18 -0400 Received: by mail-it0-f67.google.com with SMTP id t192-v6so1300856itc.1 for ; Thu, 19 Apr 2018 14:45:18 -0700 (PDT) In-Reply-To: <20180419214438.6801-1-aring@mojatatu.com> Sender: netdev-owner@vger.kernel.org List-ID: This patch checks if sk buffer is available to dererence ife header. If not then NULL will returned to signal an malformed ife packet. This avoids to crashing the kernel from outside. Signed-off-by: Alexander Aring Reviewed-by: Yotam Gigi Acked-by: Jamal Hadi Salim --- net/ife/ife.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ife/ife.c b/net/ife/ife.c index 7fbe70a0af4b..93e8c36ce6ec 100644 --- a/net/ife/ife.c +++ b/net/ife/ife.c @@ -70,6 +70,9 @@ void *ife_decode(struct sk_buff *skb, u16 *metalen) u16 ifehdrln; ifehdr = (struct ifeheadr *) (skb->data + skb->dev->hard_header_len); + if (skb->len < skb->dev->hard_header_len + IFE_METAHDRLEN) + return NULL; + ifehdrln = ntohs(ifehdr->metalen); total_pull = skb->dev->hard_header_len + ifehdrln; -- 2.11.0