linux-kernel - Re: [PATCH v2] fbdev: fix fillrect for 24bpp modes

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: <20090420160733.07e27238.akpm@linux-foundation.org>
Date:	Mon, 20 Apr 2009 16:07:33 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	spock@...too.org
Cc:	krzysztof.h1@...zta.fm, linux-fbdev-devel@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2] fbdev: fix fillrect for 24bpp modes

On Sat, 18 Apr 2009 20:52:34 +0200
Michal Januszewski <spock@...too.org> wrote:

>  		while (height--) {
> -			dst += dst_idx >> (ffs(bits) - 1);
> +			dst += dst_idx / bits;
>  			dst_idx &= (bits - 1);
> -			fill_op(p, dst, dst_idx, pat, left, right,
> +			r = dst_idx % bpp;
> +			/* rotate pattern to the correct start position */
> +#ifdef __LITTLE_ENDIAN
> +			pat2 = pat << r | pat >> (bpp-r);
> +#else
> +			pat2 = pat << (bpp-r) | pat >> r;
> +#endif
> +			fill_op(p, dst, dst_idx, pat2, left, right,
>  				width*bpp, bits);
> -			r = (p->fix.line_length*8) % bpp;
> -			pat = pat << (bpp-r) | pat >> r;
>  			dst_idx += p->fix.line_length*8;

hm, that's fairly eye-popping.

Could we do something like

	pat2 = le32_to_cpu(rol32(cpu_to_le32(pat), r));

(might be wrong, but you see what I mean...)
--
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/