[PATCH v6 3/3] media: v4l2-subdev: Verify v4l2_subdev_call() pad config argument

[Janusz Krzysztofik <jmkrzyszt@xxxxxxxxx>]

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 | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 6933f30e5041..6a5c4f046723 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -138,20 +138,30 @@ static inline int check_pad(struct v4l2_subdev *sd, __u32 pad)
 	return 0;
 }
 
+static int check_cfg(__u32 which, struct v4l2_subdev_pad_config *cfg)
+{
+	if (which == V4L2_SUBDEV_FORMAT_TRY && !cfg)
+		return -EINVAL;
+
+	return 0;
+}
+
 static inline int check_format(struct v4l2_subdev *sd,
+			       struct v4l2_subdev_pad_config *cfg,
 			       struct v4l2_subdev_format *format)
 {
 	if (!format)
 		return -EINVAL;
 
-	return check_which(format->which) ? : check_pad(sd, format->pad);
+	return check_which(format->which) ? : check_pad(sd, format->pad) ? :
+	       check_cfg(format->which, cfg);
 }
 
 static int call_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);
 }
 
@@ -159,7 +169,7 @@ static int call_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);
 }
 
@@ -171,6 +181,7 @@ static int call_enum_mbus_code(struct v4l2_subdev *sd,
 		return -EINVAL;
 
 	return check_which(code->which) ? : check_pad(sd, code->pad) ? :
+	       check_cfg(code->which, cfg) ? :
 	       sd->ops->pad->enum_mbus_code(sd, cfg, code);
 }
 
@@ -182,6 +193,7 @@ static int call_enum_frame_size(struct v4l2_subdev *sd,
 		return -EINVAL;
 
 	return check_which(fse->which) ? : check_pad(sd, fse->pad) ? :
+	       check_cfg(fse->which, cfg) ? :
 	       sd->ops->pad->enum_frame_size(sd, cfg, fse);
 }
 
@@ -216,23 +228,26 @@ static int call_enum_frame_interval(struct v4l2_subdev *sd,
 		return -EINVAL;
 
 	return check_which(fie->which) ? : check_pad(sd, fie->pad) ? :
+	       check_cfg(fie->which, cfg) ? :
 	       sd->ops->pad->enum_frame_interval(sd, cfg, fie);
 }
 
 static inline int check_selection(struct v4l2_subdev *sd,
+				  struct v4l2_subdev_pad_config *cfg,
 				  struct v4l2_subdev_selection *sel)
 {
 	if (!sel)
 		return -EINVAL;
 
-	return check_which(sel->which) ? : check_pad(sd, sel->pad);
+	return check_which(sel->which) ? : check_pad(sd, sel->pad) ? :
+	       check_cfg(sel->which, cfg);
 }
 
 static int call_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);
 }
 
@@ -240,7 +255,7 @@ static int call_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