[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20120227181434.GA13903@redhat.com>
Date: Mon, 27 Feb 2012 19:14:34 +0100
From: Oleg Nesterov <oleg@...hat.com>
To: Kees Cook <keescook@...omium.org>
Cc: Will Drewry <wad@...omium.org>, linux-kernel@...r.kernel.org,
linux-arch@...r.kernel.org, linux-doc@...r.kernel.org,
kernel-hardening@...ts.openwall.com, netdev@...r.kernel.org,
x86@...nel.org, arnd@...db.de, davem@...emloft.net, hpa@...or.com,
mingo@...hat.com, peterz@...radead.org, rdunlap@...otime.net,
mcgrathr@...omium.org, tglx@...utronix.de, luto@....edu,
eparis@...hat.com, serge.hallyn@...onical.com, djm@...drot.org,
scarybeasts@...il.com, indan@....nu, pmoore@...hat.com,
akpm@...ux-foundation.org, corbet@....net, eric.dumazet@...il.com,
markus@...omium.org, coreyb@...ux.vnet.ibm.com
Subject: Re: [PATCH v11 07/12] seccomp: add SECCOMP_RET_ERRNO
On 02/27, Kees Cook wrote:
>
> On Mon, Feb 27, 2012 at 9:11 AM, Oleg Nesterov <oleg@...hat.com> wrote:
> > On 02/24, Will Drewry wrote:
> >>
> >> static u32 seccomp_run_filters(int syscall)
> >> {
> >> struct seccomp_filter *f;
> >> - u32 ret = SECCOMP_RET_KILL;
> >> static const struct bpf_load_fn fns = {
> >> bpf_load,
> >> sizeof(struct seccomp_data),
> >> };
> >> + u32 ret = SECCOMP_RET_ALLOW;
> >> const void *sc_ptr = (const void *)(uintptr_t)syscall;
> >>
> >> + /* Ensure unexpected behavior doesn't result in failing open. */
> >> + if (unlikely(current->seccomp.filter == NULL))
> >> + ret = SECCOMP_RET_KILL;
> >
> > Is "seccomp.filter == NULL" really possible?
>
> It should not be, but I'm much more comfortable with this failing
> closed. I think it's important to be as defensive as possible with
> this code given its intended use.
Can't resists... Sorry, I know I am troll but personally I think
in this case the most defensive code is BUG_ON(->filter == NULL)
or at least WARN_ON().
Nevermind, I won't pretend I really understand the intended use,
please ignore.
Oleg.
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
