[PATCH v5 4/4] media: v4l2-subdev: Verify v4l2_subdev_call() 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 <jmkrzy...@gmail.com>
---
 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 3fc07af26c5b..fc8c308fb060 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -138,20 +138,30 @@ static int check_pad(struct v4l2_subdev *sd, __u32 pad)
        return 0;
 }
 
+static int check_cfg(__u32 which, struct v4l2_subdev_pad_config *cfg)
+{
+       if (WARN_ON(which == V4L2_SUBDEV_FORMAT_TRY && !cfg))
+               return -EINVAL;
+
+       return 0;
+}
+
 static int check_format(struct v4l2_subdev *sd,
+                       struct v4l2_subdev_pad_config *cfg,
                        struct v4l2_subdev_format *format)
 {
        if (WARN_ON(!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 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);
 }
 
@@ -159,7 +169,7 @@ 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);
 }
 
@@ -171,6 +181,7 @@ static int check_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 check_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 check_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 int check_selection(struct v4l2_subdev *sd,
+                          struct v4l2_subdev_pad_config *cfg,
                           struct v4l2_subdev_selection *sel)
 {
        if (WARN_ON(!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 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);
 }
 
@@ -240,7 +255,7 @@ 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