This is a note to let you know that I've just added the patch titled
video: fbdev: pxa3xx-gcu: Fix integer overflow in pxa3xx_gcu_write
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
video-fbdev-pxa3xx-gcu-fix-integer-overflow-in-pxa3x.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 06b856a78321aedeacaa0fbb60105aec841e90b5
Author: Hyunwoo Kim <imv4bel@xxxxxxxxx>
Date: Mon Jun 20 07:17:46 2022 -0700
video: fbdev: pxa3xx-gcu: Fix integer overflow in pxa3xx_gcu_write
[ Upstream commit a09d2d00af53b43c6f11e6ab3cb58443c2cac8a7 ]
In pxa3xx_gcu_write, a count parameter of type size_t is passed to words of
type int. Then, copy_from_user() may cause a heap overflow because it is used
as the third argument of copy_from_user().
Signed-off-by: Hyunwoo Kim <imv4bel@xxxxxxxxx>
Signed-off-by: Helge Deller <deller@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/video/fbdev/pxa3xx-gcu.c b/drivers/video/fbdev/pxa3xx-gcu.c
index 184773b6b9e4..2cca4b763d8d 100644
--- a/drivers/video/fbdev/pxa3xx-gcu.c
+++ b/drivers/video/fbdev/pxa3xx-gcu.c
@@ -391,7 +391,7 @@ pxa3xx_gcu_write(struct file *file, const char *buff,
struct pxa3xx_gcu_batch *buffer;
struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file);
- int words = count / 4;
+ size_t words = count / 4;
/* Does not need to be atomic. There's a lock in user space,
* but anyhow, this is just for statistics. */
