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

From: Hangyu Hua
Date: Thu Jun 23 2022 - 06:53:48 EST


On 2022/6/23 16:15, Krzysztof Kozlowski wrote:
On 23/06/2022 09:36, Hangyu Hua wrote:
[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")

I think only the last [3] introduced it, because it's the commit missing
put_device in first error path.


I see. Do i need to change the commit log and then send a v2?


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@xxxxxxxxx>


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>

Best regards,
Krzysztof