2021-05-09 08:29:06

by Christophe JAILLET

Subject: [PATCH] tty: serial: 8250: serial_cs: Fix a memory leak in error handling path

In the probe function, if the final 'serial_config()' fails, 'info' is
leaking.

Use 'devm_kzalloc' instead to fix the leak and simplify the .remove
function.

Signed-off-by: Christophe JAILLET <[email protected]>
---
I've not been able to find a Fixes tag. All I know is that it is old!
---
drivers/tty/serial/8250/serial_cs.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/tty/serial/8250/serial_cs.c b/drivers/tty/serial/8250/serial_cs.c
index 63ea9c4da3d5..d18c98e0d0b0 100644
--- a/drivers/tty/serial/8250/serial_cs.c
+++ b/drivers/tty/serial/8250/serial_cs.c
@@ -310,7 +310,7 @@ static int serial_probe(struct pcmcia_device *link)
dev_dbg(&link->dev, "serial_attach()\n");

/* Create new serial device */
- info = kzalloc(sizeof(*info), GFP_KERNEL);
+ info = devm_kzalloc(&link->dev, sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->p_dev = link;
@@ -325,17 +325,12 @@ static int serial_probe(struct pcmcia_device *link)

static void serial_detach(struct pcmcia_device *link)
{
- struct serial_info *info = link->priv;
-
dev_dbg(&link->dev, "serial_detach\n");

/*
* Ensure that the ports have been released.
*/
serial_remove(link);
-
- /* free bits */
- kfree(info);
}

/*====================================================================*/
--
2.30.2

2021-05-13 21:15:01

by Greg Kroah-Hartman

Subject: Re: [PATCH] tty: serial: 8250: serial_cs: Fix a memory leak in error handling path

On Sun, May 09, 2021 at 10:28:18AM +0200, Christophe JAILLET wrote:
> In the probe function, if the final 'serial_config()' fails, 'info' is
> leaking.
>
> Use 'devm_kzalloc' instead to fix the leak and simplify the .remove
> function.
>
> Signed-off-by: Christophe JAILLET <[email protected]>
> ---
> I've not been able to find a Fixes tag. All I know is that it is old!
> ---
> drivers/tty/serial/8250/serial_cs.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/serial_cs.c b/drivers/tty/serial/8250/serial_cs.c
> index 63ea9c4da3d5..d18c98e0d0b0 100644
> --- a/drivers/tty/serial/8250/serial_cs.c
> +++ b/drivers/tty/serial/8250/serial_cs.c
> @@ -310,7 +310,7 @@ static int serial_probe(struct pcmcia_device *link)
> dev_dbg(&link->dev, "serial_attach()\n");
>
> /* Create new serial device */
> - info = kzalloc(sizeof(*info), GFP_KERNEL);
> + info = devm_kzalloc(&link->dev, sizeof(*info), GFP_KERNEL);

Ick, let's not mix and only use some devm_ calls here, why not just fix
it up and free it in the error path?


thanks,

greg k-h