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@xxxxxxxxx>
Reported-by: Yang, Chenyuan <cy54@xxxxxxxxxxxx>
Fixes: ca684386e6e2 ("[media] cec: add HDMI CEC framework (api)")
Closes: https://lore.kernel.org/linux-media/PH7PR11MB57688E64ADE4FE82E658D86DA09EA@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
---
drivers/media/cec/core/cec-api.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/cec/core/cec-api.c b/drivers/media/cec/core/cec-api.c
index 67dc79ef17050..d64bb716f9c68 100644
--- a/drivers/media/cec/core/cec-api.c
+++ b/drivers/media/cec/core/cec-api.c
@@ -664,6 +664,8 @@ static int cec_release(struct inode *inode, struct file *filp)
list_del_init(&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);
@@ -681,6 +683,7 @@ static int cec_release(struct inode *inode, struct file *filp)
kfree(entry);
}
}
+ mutex_unlock(&fh->lock);
kfree(fh);
cec_put_device(devnode);
--
2.43.0
