media: v4l2-compat-ioctl32.c: fix ctrl_is_pointer

ctrl_is_pointer just hardcoded two known string controls, but that
caused problems when using e.g. custom controls that use a pointer
for the payload.

Reimplement this function: it now finds the v4l2_ctrl (if the driver
uses the control framework) or it calls vidioc_query_ext_ctrl (if the
driver implements that directly).

In both cases it can now check if the control is a pointer control
or not.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Hans Verkuil 2018-01-24 05:30:59 -05:00 committed by Mauro Carvalho Chehab
parent 8ed5a59dcb
commit b8c601e8af
1 changed files with 38 additions and 19 deletions

View File

@ -18,6 +18,8 @@
#include <linux/videodev2.h>
#include <linux/v4l2-subdev.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-ioctl.h>
static long native_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
@ -601,24 +603,39 @@ struct v4l2_ext_control32 {
};
} __attribute__ ((packed));
/* The following function really belong in v4l2-common, but that causes
a circular dependency between modules. We need to think about this, but
for now this will do. */
/* Return non-zero if this control is a pointer type. Currently only
type STRING is a pointer type. */
static inline int ctrl_is_pointer(u32 id)
/* Return true if this control is a pointer type. */
static inline bool ctrl_is_pointer(struct file *file, u32 id)
{
switch (id) {
case V4L2_CID_RDS_TX_PS_NAME:
case V4L2_CID_RDS_TX_RADIO_TEXT:
return 1;
default:
return 0;
struct video_device *vdev = video_devdata(file);
struct v4l2_fh *fh = NULL;
struct v4l2_ctrl_handler *hdl = NULL;
struct v4l2_query_ext_ctrl qec = { id };
const struct v4l2_ioctl_ops *ops = vdev->ioctl_ops;
if (test_bit(V4L2_FL_USES_V4L2_FH, &vdev->flags))
fh = file->private_data;
if (fh && fh->ctrl_handler)
hdl = fh->ctrl_handler;
else if (vdev->ctrl_handler)
hdl = vdev->ctrl_handler;
if (hdl) {
struct v4l2_ctrl *ctrl = v4l2_ctrl_find(hdl, id);
return ctrl && ctrl->is_ptr;
}
if (!ops->vidioc_query_ext_ctrl)
return false;
return !ops->vidioc_query_ext_ctrl(file, fh, &qec) &&
(qec.flags & V4L2_CTRL_FLAG_HAS_PAYLOAD);
}
static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext_controls32 __user *up)
static int get_v4l2_ext_controls32(struct file *file,
struct v4l2_ext_controls *kp,
struct v4l2_ext_controls32 __user *up)
{
struct v4l2_ext_control32 __user *ucontrols;
struct v4l2_ext_control __user *kcontrols;
@ -651,7 +668,7 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
return -EFAULT;
if (get_user(id, &kcontrols->id))
return -EFAULT;
if (ctrl_is_pointer(id)) {
if (ctrl_is_pointer(file, id)) {
void __user *s;
if (get_user(p, &ucontrols->string))
@ -666,7 +683,9 @@ static int get_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
return 0;
}
static int put_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext_controls32 __user *up)
static int put_v4l2_ext_controls32(struct file *file,
struct v4l2_ext_controls *kp,
struct v4l2_ext_controls32 __user *up)
{
struct v4l2_ext_control32 __user *ucontrols;
struct v4l2_ext_control __user *kcontrols =
@ -698,7 +717,7 @@ static int put_v4l2_ext_controls32(struct v4l2_ext_controls *kp, struct v4l2_ext
/* Do not modify the pointer when copying a pointer control.
The contents of the pointer was changed, not the pointer
itself. */
if (ctrl_is_pointer(id))
if (ctrl_is_pointer(file, id))
size -= sizeof(ucontrols->value64);
if (copy_in_user(ucontrols, kcontrols, size))
return -EFAULT;
@ -912,7 +931,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
case VIDIOC_G_EXT_CTRLS:
case VIDIOC_S_EXT_CTRLS:
case VIDIOC_TRY_EXT_CTRLS:
err = get_v4l2_ext_controls32(&karg.v2ecs, up);
err = get_v4l2_ext_controls32(file, &karg.v2ecs, up);
compatible_arg = 0;
break;
case VIDIOC_DQEVENT:
@ -939,7 +958,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
case VIDIOC_G_EXT_CTRLS:
case VIDIOC_S_EXT_CTRLS:
case VIDIOC_TRY_EXT_CTRLS:
if (put_v4l2_ext_controls32(&karg.v2ecs, up))
if (put_v4l2_ext_controls32(file, &karg.v2ecs, up))
err = -EFAULT;
break;
case VIDIOC_S_EDID: