drivers/media/usb/uvc/uvc_ctrl.c | 14 ++++++++++++-- drivers/media/usb/uvc/uvc_v4l2.c | 10 ++++++---- drivers/media/usb/uvc/uvcvideo.h | 2 +- 3 files changed, 19 insertions(+), 7 deletions(-)
The VIDIOC_G_EXT_CTRLS with which V4L2_CTRL_WHICH_(MIN|MAX)_VAL can only
work for controls that have previously announced support for it.
This patch fixes the following v4l2-compliance error:
info: checking extended control 'User Controls' (0x00980001)
fail: v4l2-test-controls.cpp(980): ret != EINVAL (got 13)
test VIDIOC_G/S/TRY_EXT_CTRLS: FAIL
Fixes: 39d2c891c96e ("media: uvcvideo: support V4L2_CTRL_WHICH_MIN/MAX_VAL")
Cc: stable@vger.kernel.org
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
Changes in v2, Thanks Laurent:
- Remove redundant ioctl check
- CodeStyle
- Link to v1: https://lore.kernel.org/r/20251028-uvc-fix-which-v1-1-a7e6b82672a3@chromium.org
---
drivers/media/usb/uvc/uvc_ctrl.c | 14 ++++++++++++--
drivers/media/usb/uvc/uvc_v4l2.c | 10 ++++++----
drivers/media/usb/uvc/uvcvideo.h | 2 +-
3 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 2905505c240c060e5034ea12d33b59d5702f2e1f..2738ef74c7373b185b67611da57610fd0b442080 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1432,7 +1432,7 @@ static bool uvc_ctrl_is_readable(u32 which, struct uvc_control *ctrl,
* auto_exposure=1, exposure_time_absolute=251.
*/
int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
- const struct v4l2_ext_controls *ctrls,
+ const struct v4l2_ext_controls *ctrls, u32 which,
unsigned long ioctl)
{
struct uvc_control_mapping *master_map = NULL;
@@ -1442,14 +1442,24 @@ int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
s32 val;
int ret;
int i;
+ /*
+ * There is no need to check the ioctl, all the ioctls except
+ * VIDIOC_G_EXT_CTRLS use which=V4L2_CTRL_WHICH_CUR_VAL.
+ */
+ bool is_which_min_max = which == V4L2_CTRL_WHICH_MIN_VAL ||
+ which == V4L2_CTRL_WHICH_MAX_VAL;
if (__uvc_query_v4l2_class(chain, v4l2_id, 0) >= 0)
- return -EACCES;
+ return is_which_min_max ? -EINVAL : -EACCES;
ctrl = uvc_find_control(chain, v4l2_id, &mapping);
if (!ctrl)
return -EINVAL;
+ if ((!(ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN) ||
+ !(ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX)) && is_which_min_max)
+ return -EINVAL;
+
if (ioctl == VIDIOC_G_EXT_CTRLS)
return uvc_ctrl_is_readable(ctrls->which, ctrl, mapping);
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index 9e4a251eca88085a1b4e0e854370015855be92ee..30c160daed8cb057b31ec00d665107dfdf4be1dc 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -765,14 +765,15 @@ static int uvc_ioctl_query_ext_ctrl(struct file *file, void *priv,
static int uvc_ctrl_check_access(struct uvc_video_chain *chain,
struct v4l2_ext_controls *ctrls,
- unsigned long ioctl)
+ u32 which, unsigned long ioctl)
{
struct v4l2_ext_control *ctrl = ctrls->controls;
unsigned int i;
int ret = 0;
for (i = 0; i < ctrls->count; ++ctrl, ++i) {
- ret = uvc_ctrl_is_accessible(chain, ctrl->id, ctrls, ioctl);
+ ret = uvc_ctrl_is_accessible(chain, ctrl->id, ctrls, which,
+ ioctl);
if (ret)
break;
}
@@ -806,7 +807,7 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *priv,
which = V4L2_CTRL_WHICH_CUR_VAL;
}
- ret = uvc_ctrl_check_access(chain, ctrls, VIDIOC_G_EXT_CTRLS);
+ ret = uvc_ctrl_check_access(chain, ctrls, which, VIDIOC_G_EXT_CTRLS);
if (ret < 0)
return ret;
@@ -840,7 +841,8 @@ static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle,
if (!ctrls->count)
return 0;
- ret = uvc_ctrl_check_access(chain, ctrls, ioctl);
+ ret = uvc_ctrl_check_access(chain, ctrls, V4L2_CTRL_WHICH_CUR_VAL,
+ ioctl);
if (ret < 0)
return ret;
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index ed7bad31f75ca474c1037d666d5310c78dd764df..d583425893a5f716185153a07aae9bfe20182964 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -786,7 +786,7 @@ int uvc_ctrl_get(struct uvc_video_chain *chain, u32 which,
struct v4l2_ext_control *xctrl);
int uvc_ctrl_set(struct uvc_fh *handle, struct v4l2_ext_control *xctrl);
int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
- const struct v4l2_ext_controls *ctrls,
+ const struct v4l2_ext_controls *ctrls, u32 which,
unsigned long ioctl);
int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
---
base-commit: c218ce4f98eccf5a40de64c559c52d61e9cc78ee
change-id: 20251028-uvc-fix-which-c3ba1fb68ed5
Best regards,
--
Ricardo Ribalda <ribalda@chromium.org>
Hi,
On 19-Nov-25 9:17 PM, Ricardo Ribalda wrote:
> The VIDIOC_G_EXT_CTRLS with which V4L2_CTRL_WHICH_(MIN|MAX)_VAL can only
> work for controls that have previously announced support for it.
>
> This patch fixes the following v4l2-compliance error:
>
> info: checking extended control 'User Controls' (0x00980001)
> fail: v4l2-test-controls.cpp(980): ret != EINVAL (got 13)
> test VIDIOC_G/S/TRY_EXT_CTRLS: FAIL
>
> Fixes: 39d2c891c96e ("media: uvcvideo: support V4L2_CTRL_WHICH_MIN/MAX_VAL")
> Cc: stable@vger.kernel.org
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Thanks patch looks good to me:
Reviewed-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
I've merged this into my local uvc/for-next branch which I will push out later
today.
Note: I've also rebased uvc/for-next on top of the latest media-committers/next
so this will be a forced push.
Regards,
Hans
> ---
> Changes in v2, Thanks Laurent:
> - Remove redundant ioctl check
> - CodeStyle
> - Link to v1: https://lore.kernel.org/r/20251028-uvc-fix-which-v1-1-a7e6b82672a3@chromium.org
> ---
> drivers/media/usb/uvc/uvc_ctrl.c | 14 ++++++++++++--
> drivers/media/usb/uvc/uvc_v4l2.c | 10 ++++++----
> drivers/media/usb/uvc/uvcvideo.h | 2 +-
> 3 files changed, 19 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index 2905505c240c060e5034ea12d33b59d5702f2e1f..2738ef74c7373b185b67611da57610fd0b442080 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1432,7 +1432,7 @@ static bool uvc_ctrl_is_readable(u32 which, struct uvc_control *ctrl,
> * auto_exposure=1, exposure_time_absolute=251.
> */
> int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> - const struct v4l2_ext_controls *ctrls,
> + const struct v4l2_ext_controls *ctrls, u32 which,
> unsigned long ioctl)
> {
> struct uvc_control_mapping *master_map = NULL;
> @@ -1442,14 +1442,24 @@ int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> s32 val;
> int ret;
> int i;
> + /*
> + * There is no need to check the ioctl, all the ioctls except
> + * VIDIOC_G_EXT_CTRLS use which=V4L2_CTRL_WHICH_CUR_VAL.
> + */
> + bool is_which_min_max = which == V4L2_CTRL_WHICH_MIN_VAL ||
> + which == V4L2_CTRL_WHICH_MAX_VAL;
>
> if (__uvc_query_v4l2_class(chain, v4l2_id, 0) >= 0)
> - return -EACCES;
> + return is_which_min_max ? -EINVAL : -EACCES;
>
> ctrl = uvc_find_control(chain, v4l2_id, &mapping);
> if (!ctrl)
> return -EINVAL;
>
> + if ((!(ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN) ||
> + !(ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX)) && is_which_min_max)
> + return -EINVAL;
> +
> if (ioctl == VIDIOC_G_EXT_CTRLS)
> return uvc_ctrl_is_readable(ctrls->which, ctrl, mapping);
>
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> index 9e4a251eca88085a1b4e0e854370015855be92ee..30c160daed8cb057b31ec00d665107dfdf4be1dc 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -765,14 +765,15 @@ static int uvc_ioctl_query_ext_ctrl(struct file *file, void *priv,
>
> static int uvc_ctrl_check_access(struct uvc_video_chain *chain,
> struct v4l2_ext_controls *ctrls,
> - unsigned long ioctl)
> + u32 which, unsigned long ioctl)
> {
> struct v4l2_ext_control *ctrl = ctrls->controls;
> unsigned int i;
> int ret = 0;
>
> for (i = 0; i < ctrls->count; ++ctrl, ++i) {
> - ret = uvc_ctrl_is_accessible(chain, ctrl->id, ctrls, ioctl);
> + ret = uvc_ctrl_is_accessible(chain, ctrl->id, ctrls, which,
> + ioctl);
> if (ret)
> break;
> }
> @@ -806,7 +807,7 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *priv,
> which = V4L2_CTRL_WHICH_CUR_VAL;
> }
>
> - ret = uvc_ctrl_check_access(chain, ctrls, VIDIOC_G_EXT_CTRLS);
> + ret = uvc_ctrl_check_access(chain, ctrls, which, VIDIOC_G_EXT_CTRLS);
> if (ret < 0)
> return ret;
>
> @@ -840,7 +841,8 @@ static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle,
> if (!ctrls->count)
> return 0;
>
> - ret = uvc_ctrl_check_access(chain, ctrls, ioctl);
> + ret = uvc_ctrl_check_access(chain, ctrls, V4L2_CTRL_WHICH_CUR_VAL,
> + ioctl);
> if (ret < 0)
> return ret;
>
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index ed7bad31f75ca474c1037d666d5310c78dd764df..d583425893a5f716185153a07aae9bfe20182964 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -786,7 +786,7 @@ int uvc_ctrl_get(struct uvc_video_chain *chain, u32 which,
> struct v4l2_ext_control *xctrl);
> int uvc_ctrl_set(struct uvc_fh *handle, struct v4l2_ext_control *xctrl);
> int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> - const struct v4l2_ext_controls *ctrls,
> + const struct v4l2_ext_controls *ctrls, u32 which,
> unsigned long ioctl);
>
> int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
>
> ---
> base-commit: c218ce4f98eccf5a40de64c559c52d61e9cc78ee
> change-id: 20251028-uvc-fix-which-c3ba1fb68ed5
>
> Best regards,
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