[PATCH AUTOSEL 4.9 135/251] media: davinci/vpbe: array underflow in vpbe_enum_outputs()

Sasha Levin
2020-01-16T18:07:49Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit b72845ee5577b227131b1fef23f9d9a296621d7b ]

In vpbe_enum_outputs() we check if (temp_index >= cfg->num_outputs) but
the problem is that "temp_index" can be negative. This patch changes
the types to unsigned to address this array underflow bug.

Fixes: 66715cdc3224 ("[media] davinci vpbe: VPBE display driver")

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: "Lad Prabhakar" <prabhakar.csengg@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/platform/davinci/vpbe.c | 2 +-
include/media/davinci/vpbe.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/davinci/vpbe.c b/drivers/media/platform/davinci/vpbe.c
index abce9c4a1a8e..59518c08528b 100644
--- a/drivers/media/platform/davinci/vpbe.c
+++ b/drivers/media/platform/davinci/vpbe.c
@@ -130,7 +130,7 @@ static int vpbe_enum_outputs(struct vpbe_device *vpbe_dev,
struct v4l2_output *output)
{
struct vpbe_config *cfg = vpbe_dev->cfg;
- int temp_index = output->index;
+ unsigned int temp_index = output->index;

if (temp_index >= cfg->num_outputs)
return -EINVAL;
diff --git a/include/media/davinci/vpbe.h b/include/media/davinci/vpbe.h
index 4376beeb28c2..5d8ceeddc797 100644
--- a/include/media/davinci/vpbe.h
+++ b/include/media/davinci/vpbe.h
@@ -96,7 +96,7 @@ struct vpbe_config {
struct encoder_config_info *ext_encoders;
/* amplifier information goes here */
struct amp_config_info *amp;
- int num_outputs;
+ unsigned int num_outputs;
/* Order is venc outputs followed by LCD and then external encoders */
struct vpbe_output *outputs;
};
--
2.20.1