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

From: Krzysztof Kozlowski
Date: Thu Jun 23 2022 - 04:15:43 EST


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.

>
> 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