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 --- drivers/media/usb/uvc/uvc_ctrl.c | 11 +++++++++-- drivers/media/usb/uvc/uvc_v4l2.c | 9 ++++++--- drivers/media/usb/uvc/uvcvideo.h | 2 +- 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c index 2905505c240c060e5034ea12d33b59d5702f2e1f..2f7d5cdd18e072a47fb5906da0f847dd449911b4 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 +1442,21 @@ int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id, s32 val; int ret; int i; + bool is_which_min_max = (ioctl == VIDIOC_G_EXT_CTRLS && + (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_MAX) || + !(ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN)) && 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..d5274dc94da3c60f1f4566b307dd445f30c4f45f 100644 --- a/drivers/media/usb/uvc/uvc_v4l2.c +++ b/drivers/media/usb/uvc/uvc_v4l2.c @@ -765,6 +765,7 @@ 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, + u32 which, unsigned long ioctl) { struct v4l2_ext_control *ctrl = ctrls->controls; @@ -772,7 +773,8 @@ static int uvc_ctrl_check_access(struct uvc_video_chain *chain, 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 +808,7 @@ 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 +842,8 @@ 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,