From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Aring Subject: [PATCH net 3/3] net: sched: ife: check on metadata length Date: Wed, 18 Apr 2018 17:35:34 -0400 Message-ID: <20180418213534.6215-4-aring@mojatatu.com> References: <20180418213534.6215-1-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-f66.google.com ([209.85.214.66]:54377 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752632AbeDRVgI (ORCPT ); Wed, 18 Apr 2018 17:36:08 -0400 Received: by mail-it0-f66.google.com with SMTP id h143-v6so4499028ita.4 for ; Wed, 18 Apr 2018 14:36:08 -0700 (PDT) In-Reply-To: <20180418213534.6215-1-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 --- net/ife/ife.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ife/ife.c b/net/ife/ife.c index 8632d2685efb..7c100034fbee 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