From: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
Alexander Viro <viro@zeniv.linux.org.uk>,
stable@vger.kernel.org
Subject: Re: [PATCH] fs/binfmt_misc.c: do not allow offset overflow
Date: Tue, 29 May 2018 19:24:47 -0300 [thread overview]
Message-ID: <20180529222445.GD4441@calabresa> (raw)
In-Reply-To: <20180529150854.f87fa3d65b9cdc0386672b1d@linux-foundation.org>
On Tue, May 29, 2018 at 03:08:54PM -0700, Andrew Morton wrote:
> On Tue, 29 May 2018 10:56:48 -0300 Thadeu Lima de Souza Cascardo <cascardo@canonical.com> wrote:
>
> > It's possible to overflow the offset to get a negative value, which might
> > crash the system, or possibly leak kernel data.
>
> I think the missing information here is "when registering a new
> binfmt_misc binary type", yes?
>
Yes, when registering a new type.
[...]
> > Cc: stable@vger.kernel.org
>
> Registering a handler is a priveleged operation. As such, I don't
> think a -stable backport is needed?
>
Not when we take containers in mind. We might question the permission to mount
a binfmt_misc inside a container, that may already have left open other ways of
exploiting the system. But I would rather see this closed on my stable systems.
Cascardo.
prev parent reply other threads:[~2018-05-29 22:24 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-29 13:56 [PATCH] fs/binfmt_misc.c: do not allow offset overflow Thadeu Lima de Souza Cascardo
2018-05-29 22:08 ` Andrew Morton
2018-05-29 22:24 ` Thadeu Lima de Souza Cascardo [this message]
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