[PATCH 3.18 025/120] media: exynos4-is: Prevent NULL pointer dereference in __isp_video_try_fmt()

Greg Kroah-Hartman
2018-10-11T15:38:35Z

From: Sylwester Nawrocki <s.nawrocki@samsung.com>

[ Upstream commit 7c1b9a5aeed91bef98988ac0fcf38c8c1f4f9a3a ]

This patch fixes potential NULL pointer dereference as indicated
by the following static checker warning:

drivers/media/platform/exynos4-is/fimc-isp-video.c:408 isp_video_try_fmt_mplane()
error: NULL dereference inside function '__isp_video_try_fmt(isp, &f->fmt.pix_mp, (0))()'.

Fixes: 34947b8aebe3: ("[media] exynos4-is: Add the FIMC-IS ISP capture DMA driver")

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/media/platform/exynos4-is/fimc-isp-video.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

--- a/drivers/media/platform/exynos4-is/fimc-isp-video.c
+++ b/drivers/media/platform/exynos4-is/fimc-isp-video.c
@@ -389,12 +389,17 @@ static void __isp_video_try_fmt(struct f
struct v4l2_pix_format_mplane *pixm,
const struct fimc_fmt **fmt)
{
- *fmt = fimc_isp_find_format(&pixm->pixelformat, NULL, 2);
+ const struct fimc_fmt *__fmt;
+
+ __fmt = fimc_isp_find_format(&pixm->pixelformat, NULL, 2);
+
+ if (fmt)
+ *fmt = __fmt;

pixm->colorspace = V4L2_COLORSPACE_SRGB;
pixm->field = V4L2_FIELD_NONE;
- pixm->num_planes = (*fmt)->memplanes;
- pixm->pixelformat = (*fmt)->fourcc;
+ pixm->num_planes = __fmt->memplanes;
+ pixm->pixelformat = __fmt->fourcc;
/*
* TODO: double check with the docmentation these width/height
* constraints are correct.