diff options
| author | Zhang Shurong <zhang_shurong@foxmail.com> | 2023-06-25 00:16:49 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-30 16:31:52 +0200 |
| commit | e32b0ad436819927cccc5d774edf675ac7bb310f (patch) | |
| tree | 8a20d28f93a01f4a6423d7f291563ea025262169 | |
| parent | 1d41b658533dbfd9a52eba14e51d0f549083b448 (diff) | |
fbdev: fix potential OOB read in fast_imageblit()
[ Upstream commit c2d22806aecb24e2de55c30a06e5d6eb297d161d ]
There is a potential OOB read at fast_imageblit, for
"colortab[(*src >> 4)]" can become a negative value due to
"const char *s = image->data, *src".
This change makes sure the index for colortab always positive
or zero.
Similar commit:
https://patchwork.kernel.org/patch/11746067
Potential bug report:
https://groups.google.com/g/syzkaller-bugs/c/9ubBXKeKXf4/m/k-QXy4UgAAAJ
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/video/fbdev/core/sysimgblt.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/video/fbdev/core/sysimgblt.c b/drivers/video/fbdev/core/sysimgblt.c index 335e92b813fc..665ef7a0a249 100644 --- a/drivers/video/fbdev/core/sysimgblt.c +++ b/drivers/video/fbdev/core/sysimgblt.c @@ -189,7 +189,7 @@ static void fast_imageblit(const struct fb_image *image, struct fb_info *p, u32 fgx = fgcolor, bgx = bgcolor, bpp = p->var.bits_per_pixel; u32 ppw = 32/bpp, spitch = (image->width + 7)/8; u32 bit_mask, eorx, shift; - const char *s = image->data, *src; + const u8 *s = image->data, *src; u32 *dst; const u32 *tab; size_t tablen; |