From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [PATCH v2] ipv4: netfilter: always let NUL terminated string ended by '\0' Date: Thu, 23 May 2013 14:26:31 +0200 Message-ID: <20130523122631.GA32141@localhost> References: <5195ECB3.5000006@asianux.com> <20130523110832.GB22553@localhost> <519E0296.6010601@asianux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kaber@trash.net, kuznet@ms2.inr.ac.ru, jmorris@namei.org, yoshfuji@linux-ipv6.org, David Miller , netfilter-devel@vger.kernel.org, netfilter@vger.kernel.org, coreteam@netfilter.org, netdev To: Chen Gang Return-path: Content-Disposition: inline In-Reply-To: <519E0296.6010601@asianux.com> Sender: netfilter-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, May 23, 2013 at 07:50:46PM +0800, Chen Gang wrote: > > For NUL terminated string, need always be sure of ended by '\0'. > > 'prefix' max length is 128 (NF_LOG_PREFIXLEN), and 'pm->prefix' max > length is 32 (ULOG_PREFIX_LEN), so really need notice it. > > 'pm' is 'struct ulog_packet_msg_t' which may be copied to user mode > (defined in "include/uapi/..."), so can not use strlcpy() instead of. That's fixing a real bug. We're passing strings that are longer than 32 bytes from nf_conntrack_tcp via nf_log, if ipt_ULOG is used, it will pass a non-null terminated string. I'm going to rework the patch description to include this and apply this patch. Thanks Chen.