[PATCH v5 3/4] media: v4l2-subdev: Verify v4l2_subdev_call() pointer arguments

[Janusz Krzysztofik <jmkrzyszt@gmail.com>]

Parameters passed to check helpers are now obtained by dereferencing
unverified pointer arguments.  Check validity of those pointers first.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 5f2264575cd7..3fc07af26c5b 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -141,6 +141,9 @@ static int check_pad(struct v4l2_subdev *sd, __u32 pad)
 static int check_format(struct v4l2_subdev *sd,
 			struct v4l2_subdev_format *format)
 {
+	if (WARN_ON(!format))
+		return -EINVAL;
+
 	return check_which(format->which) ? : check_pad(sd, format->pad);
 }
 
@@ -164,6 +167,9 @@ static int check_enum_mbus_code(struct v4l2_subdev *sd,
 				struct v4l2_subdev_pad_config *cfg,
 				struct v4l2_subdev_mbus_code_enum *code)
 {
+	if (WARN_ON(!code))
+		return -EINVAL;
+
 	return check_which(code->which) ? : check_pad(sd, code->pad) ? :
 	       sd->ops->pad->enum_mbus_code(sd, cfg, code);
 }
@@ -172,6 +178,9 @@ static int check_enum_frame_size(struct v4l2_subdev *sd,
 				 struct v4l2_subdev_pad_config *cfg,
 				 struct v4l2_subdev_frame_size_enum *fse)
 {
+	if (WARN_ON(!fse))
+		return -EINVAL;
+
 	return check_which(fse->which) ? : check_pad(sd, fse->pad) ? :
 	       sd->ops->pad->enum_frame_size(sd, cfg, fse);
 }
@@ -179,6 +188,9 @@ static int check_enum_frame_size(struct v4l2_subdev *sd,
 static int check_frame_interval(struct v4l2_subdev *sd,
 				struct v4l2_subdev_frame_interval *fi)
 {
+	if (WARN_ON(!fi))
+		return -EINVAL;
+
 	return check_pad(sd, fi->pad);
 }
 
@@ -200,6 +212,9 @@ static int check_enum_frame_interval(struct v4l2_subdev *sd,
 				struct v4l2_subdev_pad_config *cfg,
 				struct v4l2_subdev_frame_interval_enum *fie)
 {
+	if (WARN_ON(!fie))
+		return -EINVAL;
+
 	return check_which(fie->which) ? : check_pad(sd, fie->pad) ? :
 	       sd->ops->pad->enum_frame_interval(sd, cfg, fie);
 }
@@ -207,6 +222,9 @@ static int check_enum_frame_interval(struct v4l2_subdev *sd,
 static int check_selection(struct v4l2_subdev *sd,
 			   struct v4l2_subdev_selection *sel)
 {
+	if (WARN_ON(!sel))
+		return -EINVAL;
+
 	return check_which(sel->which) ? : check_pad(sd, sel->pad);
 }
 
@@ -228,6 +246,9 @@ static int check_set_selection(struct v4l2_subdev *sd,
 
 static int check_edid(struct v4l2_subdev *sd, struct v4l2_subdev_edid *edid)
 {
+	if (WARN_ON(!edid))
+		return -EINVAL;
+
 	if (WARN_ON(edid->blocks && edid->edid == NULL))
 		return -EINVAL;
 
@@ -247,6 +268,9 @@ static int check_set_edid(struct v4l2_subdev *sd, struct v4l2_subdev_edid *edid)
 static int check_dv_timings_cap(struct v4l2_subdev *sd,
 				struct v4l2_dv_timings_cap *cap)
 {
+	if (WARN_ON(!cap))
+		return -EINVAL;
+
 	return check_pad(sd, cap->pad) ? :
 	       sd->ops->pad->dv_timings_cap(sd, cap);
 }
@@ -254,6 +278,9 @@ static int check_dv_timings_cap(struct v4l2_subdev *sd,
 static int check_enum_dv_timings(struct v4l2_subdev *sd,
 				 struct v4l2_enum_dv_timings *dvt)
 {
+	if (WARN_ON(!dvt))
+		return -EINVAL;
+
 	return check_pad(sd, dvt->pad) ? :
 	       sd->ops->pad->enum_dv_timings(sd, dvt);
 }
-- 
2.21.0