iio: dummy_evgen: fix possible memleak in evgen init

iio: dummy_evgen: fix possible memleak in evgen init

[Pan Bian]

The memory allocated in the function iio_dummy_evgen_create is not
released if it fails to add the evgen device to device hierarchy. This
may result in a memory leak bug.

Signed-off-by: Pan Bian <bianpan2016@163.com>
---
 drivers/iio/dummy/iio_dummy_evgen.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/dummy/iio_dummy_evgen.c b/drivers/iio/dummy/iio_dummy_evgen.c
index efd0005..f96c0a3 100644
--- a/drivers/iio/dummy/iio_dummy_evgen.c
+++ b/drivers/iio/dummy/iio_dummy_evgen.c
@@ -196,7 +196,10 @@ static __init int iio_dummy_evgen_init(void)
 		return ret;
 	device_initialize(&iio_evgen_dev);
 	dev_set_name(&iio_evgen_dev, "iio_evgen");
-	return device_add(&iio_evgen_dev);
+	ret = device_add(&iio_evgen_dev);
+	if (ret)
+		put_device(&iio_evgen_dev);
+	return ret;
 }
 module_init(iio_dummy_evgen_init);
 
-- 
2.7.4

Re: iio: dummy_evgen: fix possible memleak in evgen init

[Jonathan Cameron]

On Thu, 18 Apr 2019 11:02:56 +0800
Pan Bian <bianpan2016@163.com> wrote:

> The memory allocated in the function iio_dummy_evgen_create is not
> released if it fails to add the evgen device to device hierarchy. This
> may result in a memory leak bug.
> 
> Signed-off-by: Pan Bian <bianpan2016@163.com>
Hi. Not sure why the patch doesn't have the standard [PATCH] prefix
in the title.

This issue has been there a long time, but as the driver is only
a testing stub I'm not going to add a fixes tag or mark it for stable.
That would just be noise I think.

Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to play with it.

Thanks,

Jonathan

> ---
>  drivers/iio/dummy/iio_dummy_evgen.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/dummy/iio_dummy_evgen.c b/drivers/iio/dummy/iio_dummy_evgen.c
> index efd0005..f96c0a3 100644
> --- a/drivers/iio/dummy/iio_dummy_evgen.c
> +++ b/drivers/iio/dummy/iio_dummy_evgen.c
> @@ -196,7 +196,10 @@ static __init int iio_dummy_evgen_init(void)
>  		return ret;
>  	device_initialize(&iio_evgen_dev);
>  	dev_set_name(&iio_evgen_dev, "iio_evgen");
> -	return device_add(&iio_evgen_dev);
> +	ret = device_add(&iio_evgen_dev);
> +	if (ret)
> +		put_device(&iio_evgen_dev);
> +	return ret;
>  }
>  module_init(iio_dummy_evgen_init);
>