From 024cd7e08896884cfd58c78cd1f2103be12e3c09 Mon Sep 17 00:00:00 2001 From: Franck Bui-Huu Date: Fri, 8 Dec 2006 02:40:48 -0800 Subject: [PATCH] softcursor.c: avoid unaligned accesses Fix 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 Cc: James Simmons Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/console/softcursor.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) (limited to 'drivers/video') diff --git a/drivers/video/console/softcursor.c b/drivers/video/console/softcursor.c index 7d07d8383569..f577bd80e020 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, struct fb_cursor *cursor) 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, struct fb_cursor *cursor) } } - 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, struct fb_cursor *cursor) 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; -- cgit v1.2.3