netdev - Re: [PATCH v2 20/20] ppc: propagate the calling conventions change down to csum_partial_copy

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: <CAHk-=wj_rmS+kQvC9DccZy=UiUFJVFG9=fQajtfSCSP1h0Rofw@mail.gmail.com>
Date:   Wed, 14 Oct 2020 15:53:00 -0700
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     "Jason A. Donenfeld" <Jason@...c4.com>
Cc:     Al Viro <viro@...iv.linux.org.uk>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-arch <linux-arch@...r.kernel.org>,
        Netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH v2 20/20] ppc: propagate the calling conventions change
 down to csum_partial_copy_generic()

On Wed, Oct 14, 2020 at 3:51 PM Linus Torvalds
<torvalds@...ux-foundation.org> wrote:
>
> I think it's this instruction:
>
>         addi    r1,r1,16
>
> that should be removed from the function exit, because Al removed the
>
> -       stwu    r1,-16(r1)
>
> on function entry.
>
> So I think you end up with a corrupt stack pointer and basically
> random behavior.
>
> Mind trying that? (This is obviously all in
> arch/powerpc/lib/checksum_32.S, the csum_partial_copy_generic()
> function).

Patch attached to make it easier to test.

NOTE! This is ENTIRELY untested. My ppc asm is so rusty that I might
be barking entirely up the wrong tree, and I just made things much
worse.

                 Linus

Download attachment "patch" of type "application/octet-stream" (471 bytes)