[PATCH 4.19 091/422] media: vicodec: fix out-of-range values when decoding

From: Greg Kroah-Hartman
Date: Tue Nov 19 2019 - 00:27:21 EST


From: Hans Verkuil <hverkuil@xxxxxxxxx>

[ Upstream commit be5a1509af8dd8a78fea24a35fe4a82d4cd0ae70 ]

While decoding you need to make sure you do not get values < 0
or > 255. Note that since this code will also be used in userspace
utilities the clamp macro isn't used since that is kernel-only.

Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/platform/vicodec/vicodec-codec.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/vicodec/vicodec-codec.c b/drivers/media/platform/vicodec/vicodec-codec.c
index 2d047646f6147..d854b2344f12b 100644
--- a/drivers/media/platform/vicodec/vicodec-codec.c
+++ b/drivers/media/platform/vicodec/vicodec-codec.c
@@ -588,8 +588,14 @@ static void fill_decoder_block(u8 *dst, const s16 *input, int stride)
int i, j;

for (i = 0; i < 8; i++) {
- for (j = 0; j < 8; j++)
- *dst++ = *input++;
+ for (j = 0; j < 8; j++, input++, dst++) {
+ if (*input < 0)
+ *dst = 0;
+ else if (*input > 255)
+ *dst = 255;
+ else
+ *dst = *input;
+ }
dst += stride - 8;
}
}
--
2.20.1