[PATCH] rpmsg: fix possible refcount leak in rpmsg_register_device_override()

[Hangyu Hua <hbh25y@gmail.com>]

[1] commit 1680939e9ecf ("rpmsg: virtio: Fix possible double free in
rpmsg_virtio_add_ctrl_dev()")
[2] commit c2eecefec5df ("rpmsg: virtio: Fix possible double free in
rpmsg_probe()")
[3] commit bb17d110cbf2 ("rpmsg: Fix calling device_lock() on
non-initialized device")

The above three patches merged at the same time introduced a new bug.
[1] and [2] make rpmsg_ns_register_device and rpmsg_ctrldev_register_device
need to call the callback function internally to free vch when it fails.
[3] has an error return path not handled vch.

Fix this by adding a put_device() to the error path.

Fixes: bb17d110cbf2 ("rpmsg: Fix calling device_lock() on non-initialized device")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---
 drivers/rpmsg/rpmsg_core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index 290c1f02da10..5a47cad89fdc 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -618,6 +618,7 @@ int rpmsg_register_device_override(struct rpmsg_device *rpdev,
 					  strlen(driver_override));
 		if (ret) {
 			dev_err(dev, "device_set_override failed: %d\n", ret);
+			put_device(dev);
 			return ret;
 		}
 	}
-- 
2.25.1