Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755032AbWKVJqm (ORCPT ); Wed, 22 Nov 2006 04:46:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755575AbWKVJqm (ORCPT ); Wed, 22 Nov 2006 04:46:42 -0500 Received: from smtp19.msg.oleane.net ([62.161.4.19]:25239 "EHLO smtp19.msg.oleane.net") by vger.kernel.org with ESMTP id S1755032AbWKVJql (ORCPT ); Wed, 22 Nov 2006 04:46:41 -0500 Message-ID: <45641CB6.5060502@innova-card.com> Date: Wed, 22 Nov 2006 10:47:34 +0100 From: Franck Bui-Huu Reply-To: Franck User-Agent: Thunderbird 1.5.0.4 (X11/20060614) MIME-Version: 1.0 To: Andrew Morton Cc: James Simmons , Linux Kernel Mailing List Subject: [PATCH] softcursor.c: avoid unaligned accesses Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3443 Lines: 100 From: Franck Bui-Huu This patch fixes some possible unaligned accesses when accessing fields of 'image' pointer. Indeed this pointer was obtained by allocating a block of memory that embeds a temporary array plus an image structure. The temporary buffer was located at the start of the allocated block and depending on its size, the image structure which comes right after can be unaligned. For example when using mini fonts (4x6) (cursor's width is 4 and its height is 6) the temporary buf size is 6 bytes. Therefore this patch moves the image structure to the start of the block and moves the temporary buffer right after. It makes 'image' pointer always aligned and since the tempo buf is a buffer of char, it's always correctly aligned as well. It also fixes the file header alignement. Signed-off-by: Franck Bui-Huu --- drivers/video/console/softcursor.c | 26 +++++++++++++------------- 1 files changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/video/console/softcursor.c b/drivers/video/console/softcursor.c index 7d07d83..f577bd8 100644 --- a/drivers/video/console/softcursor.c +++ b/drivers/video/console/softcursor.c @@ -1,11 +1,13 @@ /* - * linux/drivers/video/softcursor.c -- Generic software cursor for frame buffer devices + * linux/drivers/video/softcursor.c + * + * Generic software cursor for frame buffer devices * * Created 14 Nov 2002 by James Simmons * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file COPYING in the main directory of this archive - * for more details. + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file COPYING in the main directory of this + * archive for more details. */ #include @@ -25,7 +27,7 @@ int soft_cursor(struct fb_info *info, st unsigned int buf_align = info->pixmap.buf_align - 1; unsigned int i, size, dsize, s_pitch, d_pitch; struct fb_image *image; - u8 *dst; + u8 *src, *dst; if (info->state != FBINFO_STATE_RUNNING) return 0; @@ -45,7 +47,8 @@ int soft_cursor(struct fb_info *info, st } } - image = (struct fb_image *) (ops->cursor_src + dsize); + src = ops->cursor_src + sizeof(struct fb_image); + image = (struct fb_image *)ops->cursor_src; *image = cursor->image; d_pitch = (s_pitch + scan_align) & ~scan_align; @@ -57,21 +60,18 @@ int soft_cursor(struct fb_info *info, st switch (cursor->rop) { case ROP_XOR: for (i = 0; i < dsize; i++) - ops->cursor_src[i] = image->data[i] ^ - cursor->mask[i]; + src[i] = image->data[i] ^ cursor->mask[i]; break; case ROP_COPY: default: for (i = 0; i < dsize; i++) - ops->cursor_src[i] = image->data[i] & - cursor->mask[i]; + src[i] = image->data[i] & cursor->mask[i]; break; } } else - memcpy(ops->cursor_src, image->data, dsize); + memcpy(src, image->data, dsize); - fb_pad_aligned_buffer(dst, d_pitch, ops->cursor_src, s_pitch, - image->height); + fb_pad_aligned_buffer(dst, d_pitch, src, s_pitch, image->height); image->data = dst; info->fbops->fb_imageblit(info, image); return 0; -- 1.4.3.4 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/