2022-11-12 09:42:42

by Yang Yingliang

Subject: [PATCH] pcmcia: cs: fix possible hung task and memory leak pccardd()

If device_register() returns error in pccardd(), it leads two issues:

1. The socket_released has never been completed, it will block
pcmcia_unregister_socket(), because of waiting for completion
of socket_released.
2. The device name allocated by dev_set_name() is leaked.

Fix this two issues by calling put_device() when device_register() fails.
socket_released can be completed in pcmcia_release_socket(), the name can
be freed in kobject_cleanup().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <[email protected]>
---
drivers/pcmcia/cs.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c
index f70197154a36..820cce7c8b40 100644
--- a/drivers/pcmcia/cs.c
+++ b/drivers/pcmcia/cs.c
@@ -605,6 +605,7 @@ static int pccardd(void *__skt)
dev_warn(&skt->dev, "PCMCIA: unable to register socket\n");
skt->thread = NULL;
complete(&skt->thread_done);
+ put_device(&skt->dev);
return 0;
}
ret = pccard_sysfs_add_socket(&skt->dev);
--
2.25.1

2023-09-04 21:06:07

by Dominik Brodowski

Subject: Re: [PATCH] pcmcia: cs: fix possible hung task and memory leak pccardd()

Am Sat, Nov 12, 2022 at 05:25:41PM +0800 schrieb Yang Yingliang:
> If device_register() returns error in pccardd(), it leads two issues:
>
> 1. The socket_released has never been completed, it will block
> pcmcia_unregister_socket(), because of waiting for completion
> of socket_released.
> 2. The device name allocated by dev_set_name() is leaked.
>
> Fix this two issues by calling put_device() when device_register() fails.
> socket_released can be completed in pcmcia_release_socket(), the name can
> be freed in kobject_cleanup().
>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Yang Yingliang <[email protected]>
> ---
> drivers/pcmcia/cs.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c
> index f70197154a36..820cce7c8b40 100644
> --- a/drivers/pcmcia/cs.c
> +++ b/drivers/pcmcia/cs.c
> @@ -605,6 +605,7 @@ static int pccardd(void *__skt)
> dev_warn(&skt->dev, "PCMCIA: unable to register socket\n");
> skt->thread = NULL;
> complete(&skt->thread_done);
> + put_device(&skt->dev);
> return 0;
> }
> ret = pccard_sysfs_add_socket(&skt->dev);
> --
> 2.25.1
>

Applied to pcmcia-next, thanks!

Dominik