| Message ID | 20210316180004.1605727-13-ribalda@chromium.org |
|---|---|
| State | New |
| Headers | show |
| Series | uvcvideo: Fix v4l2-compliance errors | expand |
On 16/03/2021 19:00, Ricardo Ribalda wrote: > If an error is found when validating the list of controls passed with > VIDIOC_G_EXT_CTRLS, then error_idx shall be set to ctrls->count to > indicate to userspace that no actual hardware was touched. > > It would have been much nicer of course if error_idx could point to the > control index that failed the validation, but sadly that's not how the > API was designed. > > Fixes v4l2-compliance: > Control ioctls (Input 0): > warn: v4l2-test-controls.cpp(834): error_idx should be equal to count > warn: v4l2-test-controls.cpp(855): error_idx should be equal to count > test VIDIOC_G/S/TRY_EXT_CTRLS: OK > > Fixes: 6fa6f831f095 ("media: v4l2-ctrls: add core request support") > Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> > --- > drivers/media/v4l2-core/v4l2-ioctl.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c > index 9406e90ff805..936ae21a0e0e 100644 > --- a/drivers/media/v4l2-core/v4l2-ioctl.c > +++ b/drivers/media/v4l2-core/v4l2-ioctl.c > @@ -2294,8 +2294,12 @@ static int v4l_g_ext_ctrls(const struct v4l2_ioctl_ops *ops, > vfd, vfd->v4l2_dev->mdev, p); > if (ops->vidioc_g_ext_ctrls == NULL) > return -ENOTTY; > - return check_ext_ctrls(p, 0) ? ops->vidioc_g_ext_ctrls(file, fh, p) : > - -EINVAL; > + > + if (check_ext_ctrls(p, 0)) > + return ops->vidioc_g_ext_ctrls(file, fh, p); > + > + p->error_idx = p->count; > + return -EINVAL; > } > > static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops, > @@ -2315,8 +2319,11 @@ static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops, > vfd, vfd->v4l2_dev->mdev, p); > if (ops->vidioc_s_ext_ctrls == NULL) > return -ENOTTY; > - return check_ext_ctrls(p, 0) ? ops->vidioc_s_ext_ctrls(file, fh, p) : > - -EINVAL; > + if (check_ext_ctrls(p, 0)) > + return ops->vidioc_s_ext_ctrls(file, fh, p); > + > + p->error_idx = p->count; > + return -EINVAL; > } > > static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops, > No, this patch is wrong. In all cases where check_ext_ctrls() is called the code had already set error_idx to count. The real culprit is check_ext_ctrls() that sets error_idx to the index of the failing control. But it can only do that for the TRY ioctl. In my review of patch 1 I mentioned that adding a bool is_get is a good idea. I now this that it is best to pass the ioctl (G/S/TRY_EXT_CTRLS) instead and based on that set error_idx here. In fact, if v4l_g/s_ctrl pass G/S_CTRL as the ioctl argument to check_ext_ctrls(), then the allow_priv argument can be dropped as well, since that can be decided based on the ioctl for which this function is called. Regards, Hans
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index 9406e90ff805..936ae21a0e0e 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -2294,8 +2294,12 @@ static int v4l_g_ext_ctrls(const struct v4l2_ioctl_ops *ops, vfd, vfd->v4l2_dev->mdev, p); if (ops->vidioc_g_ext_ctrls == NULL) return -ENOTTY; - return check_ext_ctrls(p, 0) ? ops->vidioc_g_ext_ctrls(file, fh, p) : - -EINVAL; + + if (check_ext_ctrls(p, 0)) + return ops->vidioc_g_ext_ctrls(file, fh, p); + + p->error_idx = p->count; + return -EINVAL; } static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops, @@ -2315,8 +2319,11 @@ static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops, vfd, vfd->v4l2_dev->mdev, p); if (ops->vidioc_s_ext_ctrls == NULL) return -ENOTTY; - return check_ext_ctrls(p, 0) ? ops->vidioc_s_ext_ctrls(file, fh, p) : - -EINVAL; + if (check_ext_ctrls(p, 0)) + return ops->vidioc_s_ext_ctrls(file, fh, p); + + p->error_idx = p->count; + return -EINVAL; } static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops,
If an error is found when validating the list of controls passed with VIDIOC_G_EXT_CTRLS, then error_idx shall be set to ctrls->count to indicate to userspace that no actual hardware was touched. It would have been much nicer of course if error_idx could point to the control index that failed the validation, but sadly that's not how the API was designed. Fixes v4l2-compliance: Control ioctls (Input 0): warn: v4l2-test-controls.cpp(834): error_idx should be equal to count warn: v4l2-test-controls.cpp(855): error_idx should be equal to count test VIDIOC_G/S/TRY_EXT_CTRLS: OK Fixes: 6fa6f831f095 ("media: v4l2-ctrls: add core request support") Signed-off-by: Ricardo Ribalda <ribalda@chromium.org> --- drivers/media/v4l2-core/v4l2-ioctl.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)