From: Sakari Ailus <sakari.ai...@linux.intel.com>
This helps not acquiring the mutex during copying of the IOCTL argument
from or to user space.
Signed-off-by: Sakari Ailus <sakari.ai...@linux.intel.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+rene...@ideasonboard.com>
---
drivers/media/media-device.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
index c8d104d935da..3850775cc127 100644
--- a/drivers/media/media-device.c
+++ b/drivers/media/media-device.c
@@ -465,33 +465,38 @@ static long media_device_setup_link(struct media_device
*mdev,
struct media_link_desc ulink;
struct media_entity *source;
struct media_entity *sink;
- int ret;
+ int ret = -EINVAL;
if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
return -EFAULT;
+ mutex_lock(&dev->graph_mutex);
+
/* Find the source and sink entities and link.
*/
source = find_entity(mdev, ulink.source.entity);
sink = find_entity(mdev, ulink.sink.entity);
if (source == NULL || sink == NULL)
- return -EINVAL;
+ goto out;
if (ulink.source.index >= source->num_pads ||
ulink.sink.index >= sink->num_pads)
- return -EINVAL;
+ goto out;
link = media_entity_find_link(&source->pads[ulink.source.index],
&sink->pads[ulink.sink.index]);
if (link == NULL)
- return -EINVAL;
+ goto out;
/* Setup the link on both entities. */
ret = __media_entity_setup_link(link, ulink.flags);
- if (copy_to_user(_ulink, &ulink, sizeof(ulink)))
- return -EFAULT;
+out:
+ mutex_unlock(&dev->graph_mutex);
+
+ if (!ret && copy_to_user(_ulink, &ulink, sizeof(ulink)))
+ ret = -EFAULT;
return ret;
}
@@ -523,10 +528,8 @@ static long media_device_ioctl(struct file *filp, unsigned
int cmd,
break;
case MEDIA_IOC_SETUP_LINK:
- mutex_lock(&dev->graph_mutex);
ret = media_device_setup_link(dev,
(struct media_link_desc __user *)arg);
- mutex_unlock(&dev->graph_mutex);
break;
case MEDIA_IOC_REQUEST_CMD:
--
2.4.10
