[PATCH v6 2/3] media: v4l2-subdev: Verify v4l2_subdev_call() pointer arguments

[Janusz Krzysztofik]

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

Signed-off-by: Janusz Krzysztofik <jmkrzy...@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 c61c95007d89..6933f30e5041 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -141,6 +141,9 @@ static inline int check_pad(struct v4l2_subdev *sd, __u32 
pad)
 static inline int check_format(struct v4l2_subdev *sd,
                               struct v4l2_subdev_format *format)
 {
+       if (!format)
+               return -EINVAL;
+
        return check_which(format->which) ? : check_pad(sd, format->pad);
 }
 
@@ -164,6 +167,9 @@ static int call_enum_mbus_code(struct v4l2_subdev *sd,
                               struct v4l2_subdev_pad_config *cfg,
                               struct v4l2_subdev_mbus_code_enum *code)
 {
+       if (!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 call_enum_frame_size(struct v4l2_subdev *sd,
                                struct v4l2_subdev_pad_config *cfg,
                                struct v4l2_subdev_frame_size_enum *fse)
 {
+       if (!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 call_enum_frame_size(struct v4l2_subdev *sd,
 static inline int check_frame_interval(struct v4l2_subdev *sd,
                                       struct v4l2_subdev_frame_interval *fi)
 {
+       if (!fi)
+               return -EINVAL;
+
        return check_pad(sd, fi->pad);
 }
 
@@ -200,6 +212,9 @@ static int call_enum_frame_interval(struct v4l2_subdev *sd,
                                    struct v4l2_subdev_pad_config *cfg,
                                    struct v4l2_subdev_frame_interval_enum *fie)
 {
+       if (!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 call_enum_frame_interval(struct v4l2_subdev *sd,
 static inline int check_selection(struct v4l2_subdev *sd,
                                  struct v4l2_subdev_selection *sel)
 {
+       if (!sel)
+               return -EINVAL;
+
        return check_which(sel->which) ? : check_pad(sd, sel->pad);
 }
 
@@ -229,6 +247,9 @@ static int call_set_selection(struct v4l2_subdev *sd,
 static inline int check_edid(struct v4l2_subdev *sd,
                             struct v4l2_subdev_edid *edid)
 {
+       if (!edid)
+               return -EINVAL;
+
        if (edid->blocks && edid->edid == NULL)
                return -EINVAL;
 
@@ -248,6 +269,9 @@ static int call_set_edid(struct v4l2_subdev *sd, struct 
v4l2_subdev_edid *edid)
 static int call_dv_timings_cap(struct v4l2_subdev *sd,
                               struct v4l2_dv_timings_cap *cap)
 {
+       if (!cap)
+               return -EINVAL;
+
        return check_pad(sd, cap->pad) ? :
               sd->ops->pad->dv_timings_cap(sd, cap);
 }
@@ -255,6 +279,9 @@ static int call_dv_timings_cap(struct v4l2_subdev *sd,
 static int call_enum_dv_timings(struct v4l2_subdev *sd,
                                struct v4l2_enum_dv_timings *dvt)
 {
+       if (!dvt)
+               return -EINVAL;
+
        return check_pad(sd, dvt->pad) ? :
               sd->ops->pad->enum_dv_timings(sd, dvt);
 }
-- 
2.21.0