linux-kernel - Re: crypto_memneq not backported to 3.10

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHmME9r9Jj=WtQxhxqtwWHFxwJV6KzMWO7qdsvhfG8R3B1qbJw@mail.gmail.com>
Date:   Mon, 1 May 2017 16:30:01 +0200
From:   "Jason A. Donenfeld" <Jason@...c4.com>
To:     Willy Tarreau <w@....eu>
Cc:     stable@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>,
        Linux Crypto Mailing List <linux-crypto@...r.kernel.org>,
        security@...nel.org
Subject: Re: crypto_memneq not backported to 3.10

Hey Willy,

On Sun, Apr 9, 2017 at 3:25 PM, Willy Tarreau <w@....eu> wrote:
>
> Hi Jason,
>
> On Sun, Apr 09, 2017 at 02:59:53PM +0200, Jason A. Donenfeld wrote:
> > Hey Willy,
> >
> > Linux 3.10 is inexplicably missing crypto_memneq, making all crypto
> > mac comparisons use non constant-time comparisons. Bad news bears.
> >
> > 3.12 got these backported with
> > d68e944a8fcb2c6212b38064771c9f5af7b0b92c,
> > afe5a791d374e50a06ada7f4eda4e921e1b77996, and possibly others. I'd
> > suggest following suit, since many people are relying on this kernel
> > to do safe crypto.
>
> Interesting. I remembered seeing some crypto_memneq stuff in the past,
> and in fact there was one patch talking about this but trimmed down to
> only affect other parts since crypto_memneq is indeed not part of 3.10.
>
> I'll check if the 3.12 patches above can be safely backported, and I'll
> have to re-apply the missing part of the one that was trimmed down
> (commit 620c411 ("crypto: more robust crypto_memneq")).

I'm vaguely wondering if you ever decided on backporting this. After I
reported the issue to Ubiquiti -- a random vendor doing ipsec with
3.10 -- they actually released a backport of these functions in a
security update for their stuff. So I imagine others might want this
sort of thing too.

Jason