From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [patch -mainline] netfilter: ipset: small potential read beyond the end of buffer Date: Mon, 10 Nov 2014 17:11:21 +0100 Message-ID: <20141110161121.GA7398@salvia> References: <20141107062140.GA10905@mwanda> <20141110142446.GA29586@salvia> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="UlVJffcvxoiEqYs2" Cc: Dan Carpenter , Patrick McHardy , "David S. Miller" , Sergey Popovich , Masanari Iida , Anton Danilov , stephen hemminger , netfilter-devel@vger.kernel.org, coreteam@netfilter.org, netdev@vger.kernddel.org, kernel-janitors@vger.kernel.org To: Jozsef Kadlecsik Return-path: Received: from mail.us.es ([193.147.175.20]:57530 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751292AbaKJQJg (ORCPT ); Mon, 10 Nov 2014 11:09:36 -0500 Content-Disposition: inline In-Reply-To: Sender: netfilter-devel-owner@vger.kernel.org List-ID: --UlVJffcvxoiEqYs2 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Nov 10, 2014 at 03:27:51PM +0100, Jozsef Kadlecsik wrote: > On Mon, 10 Nov 2014, Pablo Neira Ayuso wrote: > > >From other similar code in that location, I can see Jozsef is using > > this pattern: > > > > if (*len != sizeof(struct ip_set_req_version)) { > > ret = -EINVAL; > > goto done; > > } > > > > I think it would be good to stick to that for consistency. Thanks. > > Absolutely, yes. > > Acked-by: Jozsef Kadlecsik OK, then does this look fine to you? I took over Dan's patch and gave it another spin. See it attached, thanks. --UlVJffcvxoiEqYs2 Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="0001-netfilter-ipset-small-potential-read-beyond-the-end-.patch" >>From d67bad383d4ea9dea8872e3999324ccbeb2a5815 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 7 Nov 2014 09:21:40 +0300 Subject: [PATCH] netfilter: ipset: small potential read beyond the end of buffer We could be reading 8 bytes into a 4 byte buffer here. It seems harmless but adding a check is the right thing to do and it silences a static checker warning. Signed-off-by: Dan Carpenter Signed-off-by: Pablo Neira Ayuso --- net/netfilter/ipset/ip_set_core.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index 86f9d76..d259da3 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -1863,6 +1863,12 @@ ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len) if (*op < IP_SET_OP_VERSION) { /* Check the version at the beginning of operations */ struct ip_set_req_version *req_version = data; + + if (*len < sizeof(struct ip_set_req_version)) { + ret = -EINVAL; + goto done; + } + if (req_version->version != IPSET_PROTOCOL) { ret = -EPROTO; goto done; -- 1.7.10.4 --UlVJffcvxoiEqYs2--