[PATCH v4 2/2] media: v4l2-subdev: Verify pad config argument

[Janusz Krzysztofik]

Extend parameter checks performed by v4l2_subdev_call() with a check for
a non-NULL pad config pointer if V4L2_SUBDEV_FORMAT_TRY format type is
requested so drivers don't need to care.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 30 +++++++++++++++++++--------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index cd50fcb86c47..4540d8abff5f 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -126,6 +126,11 @@ static inline int check_which(__u32 which)
 	       which != V4L2_SUBDEV_FORMAT_ACTIVE ? -EINVAL : 0;
 }
 
+static inline int check_cfg(__u32 which, struct v4l2_subdev_pad_config *cfg)
+{
+	return which == V4L2_SUBDEV_FORMAT_TRY && !cfg ? -EINVAL : 0;
+}
+
 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
 static inline int check_pad(struct v4l2_subdev *sd, __u32 pad)
 {
@@ -136,16 +141,18 @@ static inline int check_pad(struct v4l2_subdev *sd, __u32 pad)
 #endif
 
 static int check_format(struct v4l2_subdev *sd,
+			struct v4l2_subdev_pad_config *cfg,
 			struct v4l2_subdev_format *format)
 {
-	return check_which(format->which) ? : check_pad(sd, format->pad);
+	return check_which(format->which) ? :
+	       check_cfg(format->which, cfg) ? : check_pad(sd, format->pad);
 }
 
 static int check_get_fmt(struct v4l2_subdev *sd,
 			 struct v4l2_subdev_pad_config *cfg,
 			 struct v4l2_subdev_format *format)
 {
-	return check_format(sd, format) ? :
+	return check_format(sd, cfg, format) ? :
 	       sd->ops->pad->get_fmt(sd, cfg, format);
 }
 
@@ -153,7 +160,7 @@ static int check_set_fmt(struct v4l2_subdev *sd,
 			 struct v4l2_subdev_pad_config *cfg,
 			 struct v4l2_subdev_format *format)
 {
-	return check_format(sd, format) ? :
+	return check_format(sd, cfg, format) ? :
 	       sd->ops->pad->set_fmt(sd, cfg, format);
 }
 
@@ -161,7 +168,8 @@ static int check_enum_mbus_code(struct v4l2_subdev *sd,
 				struct v4l2_subdev_pad_config *cfg,
 				struct v4l2_subdev_mbus_code_enum *code)
 {
-	return check_which(code->which) ? : check_pad(sd, code->pad) ? :
+	return check_which(code->which) ? : check_cfg(code->which, cfg) ? :
+	       check_pad(sd, code->pad) ? :
 	       sd->ops->pad->enum_mbus_code(sd, cfg, code);
 }
 
@@ -169,7 +177,8 @@ static int check_enum_frame_size(struct v4l2_subdev *sd,
 				 struct v4l2_subdev_pad_config *cfg,
 				 struct v4l2_subdev_frame_size_enum *fse)
 {
-	return check_which(fse->which) ? : check_pad(sd, fse->pad) ? :
+	return check_which(fse->which) ? : check_cfg(fse->which, cfg) ? :
+	       check_pad(sd, fse->pad) ? :
 	       sd->ops->pad->enum_frame_size(sd, cfg, fse);
 }
 
@@ -197,21 +206,24 @@ static int check_enum_frame_interval(struct v4l2_subdev *sd,
 				struct v4l2_subdev_pad_config *cfg,
 				struct v4l2_subdev_frame_interval_enum *fie)
 {
-	return check_which(fie->which) ? : check_pad(sd, fie->pad) ? :
+	return check_which(fie->which) ? : check_cfg(fie->which, cfg) ? :
+	       check_pad(sd, fie->pad) ? :
 	       sd->ops->pad->enum_frame_interval(sd, cfg, fie);
 }
 
 static int check_selection(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_pad_config *cfg,
 			   struct v4l2_subdev_selection *sel)
 {
-	return check_which(sel->which) ? : check_pad(sd, sel->pad);
+	return check_which(sel->which) ? : check_cfg(sel->which, cfg) ? :
+	       check_pad(sd, sel->pad);
 }
 
 static int check_get_selection(struct v4l2_subdev *sd,
 			       struct v4l2_subdev_pad_config *cfg,
 			       struct v4l2_subdev_selection *sel)
 {
-	return check_selection(sd, sel) ? :
+	return check_selection(sd, cfg, sel) ? :
 	       sd->ops->pad->get_selection(sd, cfg, sel);
 }
 
@@ -219,7 +231,7 @@ static int check_set_selection(struct v4l2_subdev *sd,
 			       struct v4l2_subdev_pad_config *cfg,
 			       struct v4l2_subdev_selection *sel)
 {
-	return check_selection(sd, sel) ? :
+	return check_selection(sd, cfg, sel) ? :
 	       sd->ops->pad->set_selection(sd, cfg, sel);
 }
 
-- 
2.21.0