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 for Android: free password hash cracker in your pocket
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <AANLkTikKA2MY6nf+LLyJbNQffX=qYY3eZdpNmwVQc21u@mail.gmail.com>
Date:	Wed, 30 Mar 2011 20:02:50 +0200
From:	Geert Uytterhoeven <geert@...ux-m68k.org>
To:	Akinobu Mita <akinobu.mita@...il.com>,
	Andreas Schwab <schwab@...ux-m68k.org>
Cc:	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	Roman Zippel <zippel@...ux-m68k.org>,
	linux-m68k@...r.kernel.org,
	Michael Schmitz <schmitzmic@...glemail.com>
Subject: Re: [PATCH] m68k: fix find_next bitops

On Fri, Mar 25, 2011 at 12:00, Akinobu Mita <akinobu.mita@...il.com> wrote:
> find_next bitops on m68k (find_next_zero_bit, find_next_bit, and
> find_next_bit_le) may cause out of bounds memory access
> when the bitmap size in bits % 32 != 0 and offset (the bitnumber
> to start searching at) is very close to the bitmap size.
>
> For example,
>
>       unsigned long bitmap[2] = { 0, 0 };
>       find_next_bit(bitmap, 63, 62);
>
> 1. find_next_bit() tries to find any set bits in bitmap[1],
>   but no bits set.
>
> 2. Then find_first_bit(bimap + 2, -1)
>
> 3. Unfortunately find_fist_bit() takes unsigned int as the size argument.
>
> 4. find_first_bit will access bitmap[2~] until it find any set bits.
>
> This switches find_next bitops to use generic implementation of
> find bitops to fix the problem.

Andreas, do you think it's worth keeping (and fixing) the m68k "optimized"
versions?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ