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| author | Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> | 2020-08-31 19:37:00 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-04 17:27:10 +0200 |
| commit | bd018a6a75cebb511bb55a0e7690024be975fe93 (patch) | |
| tree | e9081c7d9452a291f4076e501c189736410c949a /drivers/video/fbdev | |
| parent | 42f07816ac0cc797928119cc039c414ae2b95d34 (diff) | |
| download | lwn-bd018a6a75cebb511bb55a0e7690024be975fe93.tar.gz lwn-bd018a6a75cebb511bb55a0e7690024be975fe93.zip | |
video: fbdev: fix OOB read in vga_8planes_imageblit()
syzbot is reporting OOB read at vga_8planes_imageblit() [1], for
"cdat[y] >> 4" can become a negative value due to "const char *cdat".
[1] https://syzkaller.appspot.com/bug?id=0d7a0da1557dcd1989e00cb3692b26d4173b4132
Reported-by: syzbot <syzbot+69fbd3e01470f169c8c4@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/90b55ec3-d5b0-3307-9f7c-7ff5c5fd6ad3@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/video/fbdev')
| -rw-r--r-- | drivers/video/fbdev/vga16fb.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/video/fbdev/vga16fb.c b/drivers/video/fbdev/vga16fb.c index a20eeb8308ff..578d3541e3d6 100644 --- a/drivers/video/fbdev/vga16fb.c +++ b/drivers/video/fbdev/vga16fb.c @@ -1121,7 +1121,7 @@ static void vga_8planes_imageblit(struct fb_info *info, const struct fb_image *i char oldop = setop(0); char oldsr = setsr(0); char oldmask = selectmask(); - const char *cdat = image->data; + const unsigned char *cdat = image->data; u32 dx = image->dx; char __iomem *where; int y; |