media: cec: cec-api: add locking in cec_release()

[ Upstream commit 42bcaacae9 ]

When cec_release() uses fh->msgs it has to take fh->lock,
otherwise the list can get corrupted.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: Yang, Chenyuan <cy54@illinois.edu>
Closes: https://lore.kernel.org/linux-media/PH7PR11MB57688E64ADE4FE82E658D86DA09EA@PH7PR11MB5768.namprd11.prod.outlook.com/
Fixes: ca684386e6 ("[media] cec: add HDMI CEC framework (api)")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Hans Verkuil 2024-02-23 12:25:55 +00:00 committed by Greg Kroah-Hartman
parent 896dfd4d74
commit d2cfbc5298

View File

@ -660,6 +660,8 @@ static int cec_release(struct inode *inode, struct file *filp)
list_del(&data->xfer_list);
}
mutex_unlock(&adap->lock);
mutex_lock(&fh->lock);
while (!list_empty(&fh->msgs)) {
struct cec_msg_entry *entry =
list_first_entry(&fh->msgs, struct cec_msg_entry, list);
@ -677,6 +679,7 @@ static int cec_release(struct inode *inode, struct file *filp)
kfree(entry);
}
}
mutex_unlock(&fh->lock);
kfree(fh);
cec_put_device(devnode);