[PATCH v6 1/5] media: uvcvideo: Only save async fh if success

Ricardo Ribalda
2024-12-03T21:20:19Z

Now we keep a reference to the active fh for any call to uvc_ctrl_set,
regardless if it is an actual set or if it is a just a try or if the
device refused the operation.

We should only keep the file handle if the device actually accepted
applying the operation.

Cc: stable@vger.kernel.org
Fixes: e5225c820c05 ("media: uvcvideo: Send a control event when a Control Change interrupt arrives")
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
drivers/media/usb/uvc/uvc_ctrl.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 4fe26e82e3d1..9a80a7d8e73a 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1811,7 +1811,10 @@ int uvc_ctrl_begin(struct uvc_video_chain *chain)
}

static int uvc_ctrl_commit_entity(struct uvc_device *dev,
- struct uvc_entity *entity, int rollback, struct uvc_control **err_ctrl)
+ struct uvc_fh *handle,
+ struct uvc_entity *entity,
+ int rollback,
+ struct uvc_control **err_ctrl)
{
struct uvc_control *ctrl;
unsigned int i;
@@ -1859,6 +1862,10 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
*err_ctrl = ctrl;
return ret;
}
+
+ if (!rollback && handle &&
+ ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
+ ctrl->handle = handle;
}

return 0;
@@ -1895,8 +1902,8 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,

/* Find the control. */
list_for_each_entry(entity, &chain->entities, chain) {
- ret = uvc_ctrl_commit_entity(chain->dev, entity, rollback,
- &err_ctrl);
+ ret = uvc_ctrl_commit_entity(chain->dev, handle, entity,
+ rollback, &err_ctrl);
if (ret < 0) {
if (ctrls)
ctrls->error_idx =
@@ -2046,9 +2053,6 @@ int uvc_ctrl_set(struct uvc_fh *handle,
mapping->set(mapping, value,
uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));

- if (ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
- ctrl->handle = handle;
-
ctrl->dirty = 1;
ctrl->modified = 1;
return 0;
@@ -2377,7 +2381,7 @@ int uvc_ctrl_restore_values(struct uvc_device *dev)
ctrl->dirty = 1;
}

- ret = uvc_ctrl_commit_entity(dev, entity, 0, NULL);
+ ret = uvc_ctrl_commit_entity(dev, NULL, entity, 0, NULL);
if (ret < 0)
return ret;
}

--
2.47.0.338.g60cca15819-goog