[PATCH 3.19.y-ckt 016/130] Input: zforce - don't overwrite the stack

[Kamal Mostafa]

On Thu, 2015-08-27 at 15:24 -0700, Dmitry Torokhov wrote:
> On August 27, 2015 3:10:07 PM PDT, Kamal Mostafa <kamal at canonical.com> wrote:
> >3.19.8-ckt6 -stable review patch.  If anyone has any objections, please
> >let me know.
> 
> Bad patch, reverted in mainline, please drop.

OK, dropped from 3.19-stable.  Thanks Dmitry!

 -Kamal

> >
> >------------------
> >
> >From: Oleksij Rempel <external.Oleksij.Rempel at de.bosch.com>
> >
> >commit 7d01cd261c76f95913c81554a751968a1d282d3a upstream.
> >
> >If we get a corrupted packet with PAYLOAD_LENGTH > FRAME_MAXSIZE, we
> >will silently overwrite the stack.
> >
> >Signed-off-by: Oleksij Rempel <external.Oleksij.Rempel at de.bosch.com>
> >Signed-off-by: Dirk Behme <dirk.behme at de.bosch.com>
> >Signed-off-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
> >Signed-off-by: Kamal Mostafa <kamal at canonical.com>
> >---
> > drivers/input/touchscreen/zforce_ts.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> >diff --git a/drivers/input/touchscreen/zforce_ts.c
> >b/drivers/input/touchscreen/zforce_ts.c
> >index 19880c7..a9e1ee3 100644
> >--- a/drivers/input/touchscreen/zforce_ts.c
> >+++ b/drivers/input/touchscreen/zforce_ts.c
> >@@ -430,7 +430,7 @@ static int zforce_read_packet(struct zforce_ts *ts,
> >u8 *buf)
> > 		goto unlock;
> > 	}
> > 
> >-	if (buf[PAYLOAD_LENGTH] == 0) {
> >+	if (buf[PAYLOAD_LENGTH] == 0 || buf[PAYLOAD_LENGTH] > FRAME_MAXSIZE)
> >{
> > 		dev_err(&client->dev, "invalid payload length: %d\n",
> > 			buf[PAYLOAD_LENGTH]);
> > 		ret = -EIO;
> 
> 
> Thanks.
>