Re: [PATCH RESEND] fpga: region: Fix possible memory leak in fpga_region_register_full()

From: Xu Yilun
Date: Thu Sep 28 2023 - 10:03:32 EST


On Thu, Sep 28, 2023 at 05:16:36PM +0800, Jinjie Ruan wrote:
> If device_register() fails in fpga_region_register_full(), the region
> allocated by kzalloc() and the id allocated by ida_alloc() also need be
> freed otherwise will cause memory leak.

How did you observe the memory leak? Please help provide some trace.

Thanks,
Yilun

>
> Fixes: 8886a579744f ("fpga: region: Use standard dev_release for class driver")
> Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
> ---
> drivers/fpga/fpga-region.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
> index b364a929425c..9dc6314976ef 100644
> --- a/drivers/fpga/fpga-region.c
> +++ b/drivers/fpga/fpga-region.c
> @@ -228,12 +228,13 @@ fpga_region_register_full(struct device *parent, const struct fpga_region_info *
>
> ret = device_register(&region->dev);
> if (ret) {
> - put_device(&region->dev);
> - return ERR_PTR(ret);
> + goto err_put_device;
> }
>
> return region;
>
> +err_put_device:
> + put_device(&region->dev);
> err_remove:
> ida_free(&fpga_region_ida, id);
> err_free:
> --
> 2.34.1
>