From: Florian Westphal <fw@strlen.de>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Florian Westphal <fw@strlen.de>, peter pi <tiangangpi@gmail.com>,
Jan Engelhardt <jengelh@inai.de>,
Eric Dumazet <eric.dumazet@gmail.com>,
Greg Hackmann <ghackmann@google.com>,
Pablo Neira Ayuso <pablo@netfilter.org>,
Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>,
Michal Kubecek <mkubecek@suse.cz>,
netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
netdev@vger.kernel.org
Subject: Re: [PATCH v2] netfilter: properly initialize xt_table_info structure
Date: Thu, 31 May 2018 11:07:58 +0200 [thread overview]
Message-ID: <20180531090758.gwvbzpd4iu74yakj@breakpoint.cc> (raw)
In-Reply-To: <20180531085116.GA17729@kroah.com>
Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
> On Thu, May 31, 2018 at 10:24:36AM +0200, Florian Westphal wrote:
> > peter pi <tiangangpi@gmail.com> wrote:
> > > Hi Greg, I applied this patch on 4.4 and tested it on my Pixel 2, it seems
> > > the problem still exists,
> >
> > What is the problem exactly?
>
> The problem is that kernel data is being sent to userspace due to an
> uncleared buffer that was allocated and then copied to userspace. This
> can be reproduced by dumping the current set of iptables rules. Peter
> had an example reproducing script that he used to specifically show
> this. Peter, can you provide that?
>
> I thought that initializing this buffer to zero would solve the problem,
> but I guess I cleared the wrong buffer :(
Never mind, this test was on 4.4 not 4.14.
But even on 4.14 i don't see how zeroing a buffer that will
be filled via copy_from_user would help.
next prev parent reply other threads:[~2018-05-31 9:07 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-17 8:44 [PATCH] netfilter: properly initialize xt_table_info structure Greg Kroah-Hartman
2018-05-17 8:59 ` Michal Kubecek
2018-05-17 9:29 ` Greg Kroah-Hartman
2018-05-17 9:34 ` [PATCH v2] " Greg Kroah-Hartman
2018-05-17 9:55 ` Eric Dumazet
2018-05-17 10:09 ` Greg Kroah-Hartman
2018-05-17 10:42 ` Jan Engelhardt
2018-05-17 13:20 ` Greg Kroah-Hartman
2018-05-18 9:27 ` Florian Westphal
2018-05-18 11:04 ` Greg Kroah-Hartman
2018-05-26 14:54 ` Greg Kroah-Hartman
[not found] ` <CANZU63WyNL4qUJx2eS3gokPMBJLn5=C4-bnOSEF5trX3jGngUA@mail.gmail.com>
2018-05-31 8:24 ` Florian Westphal
2018-05-31 8:51 ` Greg Kroah-Hartman
2018-05-31 9:07 ` Florian Westphal [this message]
2018-05-31 10:11 ` Greg Kroah-Hartman
[not found] ` <CANZU63VE7fWNL+PJrLp7-5PBS6R6RQPvhw2QgqAK8NhX4uQc9Q@mail.gmail.com>
2018-05-31 11:23 ` Greg Kroah-Hartman
2018-05-31 11:32 ` Michal Kubecek
2018-05-31 11:55 ` Michal Kubecek
2018-05-31 16:25 ` Greg Kroah-Hartman
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