From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Aring Subject: [PATCHv4 net 3/3] net: sched: ife: check on metadata length Date: Fri, 20 Apr 2018 15:15:05 -0400 Message-ID: <20180420191505.27633-4-aring@mojatatu.com> References: <20180420191505.27633-1-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-io0-f194.google.com ([209.85.223.194]:36209 "EHLO mail-io0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752159AbeDTTQI (ORCPT ); Fri, 20 Apr 2018 15:16:08 -0400 Received: by mail-io0-f194.google.com with SMTP id c26-v6so11732674iob.3 for ; Fri, 20 Apr 2018 12:16:07 -0700 (PDT) In-Reply-To: <20180420191505.27633-1-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..13bbf8cb6a39 100644 --- a/net/ife/ife.c +++ b/net/ife/ife.c @@ -69,6 +69,9 @@ void *ife_decode(struct sk_buff *skb, u16 *metalen) int total_pull; u16 ifehdrln; + if (!pskb_may_pull(skb, skb->dev->hard_header_len + IFE_METAHDRLEN)) + return NULL; + ifehdr = (struct ifeheadr *) (skb->data + skb->dev->hard_header_len); ifehdrln = ntohs(ifehdr->metalen); total_pull = skb->dev->hard_header_len + ifehdrln; -- 2.11.0