From: Hans Verkuil hverkuil-cisco@xs4all.nl
[ Upstream commit e91c255733d9bbb4978a372f44fb5ed689ccdbd1 ]
If a CEC device node is unregistered, then it should be marked as unregistered before waking up any filehandles that are waiting for an event.
This ensures that there is no race condition where an application can call CEC_DQEVENT and have the ioctl return 0 instead of ENODEV.
Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/cec/cec-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/media/cec/cec-core.c b/drivers/media/cec/cec-core.c index 648136e552d5b..7c585e05c6311 100644 --- a/drivers/media/cec/cec-core.c +++ b/drivers/media/cec/cec-core.c @@ -175,12 +175,12 @@ static void cec_devnode_unregister(struct cec_devnode *devnode) mutex_unlock(&devnode->lock); return; } + devnode->registered = false; + devnode->unregistered = true;
list_for_each_entry(fh, &devnode->fhs, list) wake_up_interruptible(&fh->wait);
- devnode->registered = false; - devnode->unregistered = true; mutex_unlock(&devnode->lock);
cdev_device_del(&devnode->cdev, &devnode->dev);