Re: [PATCH] memory: brcmstb_dpfe: Fix memory leak

From: Krzysztof Kozlowski
Date: Thu Aug 20 2020 - 11:29:52 EST


On Tue, Aug 18, 2020 at 12:02:01PM +0100, Alex Dewar wrote:
> In brcmstb_dpfe_download_firmware(), memory is allocated to variable fw by
> firmware_request_nowarn(), but never released. Fix up to release fw on
> all return paths.
>
> Signed-off-by: Alex Dewar <alex.dewar90@xxxxxxxxx>
> ---
> drivers/memory/brcmstb_dpfe.c | 18 +++++++++++-------
> 1 file changed, 11 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
> index 60e8633b1175..f24a9dc65f3c 100644
> --- a/drivers/memory/brcmstb_dpfe.c
> +++ b/drivers/memory/brcmstb_dpfe.c
> @@ -616,7 +616,7 @@ static int brcmstb_dpfe_download_firmware(struct brcmstb_dpfe_priv *priv)
> const u32 *dmem, *imem;
> struct init_data init;
> const void *fw_blob;
> - int ret;
> + int ret = 0;

This does not look needed. Why initializing it? You cannot jump to
release_fw label or reach it without going through assignment.

Best regards,
Krzysztof

>
> /*
> * Skip downloading the firmware if the DCPU is already running and
> @@ -647,8 +647,10 @@ static int brcmstb_dpfe_download_firmware(struct brcmstb_dpfe_priv *priv)
> return (ret == -ENOENT) ? -EPROBE_DEFER : ret;
>
> ret = __verify_firmware(&init, fw);
> - if (ret)
> - return -EFAULT;
> + if (ret) {
> + ret = -EFAULT;
> + goto release_fw;
> + }
>
> __disable_dcpu(priv);
>
> @@ -667,18 +669,20 @@ static int brcmstb_dpfe_download_firmware(struct brcmstb_dpfe_priv *priv)
>
> ret = __write_firmware(priv->dmem, dmem, dmem_size, is_big_endian);
> if (ret)
> - return ret;
> + goto release_fw;
> ret = __write_firmware(priv->imem, imem, imem_size, is_big_endian);
> if (ret)
> - return ret;
> + goto release_fw;
>
> ret = __verify_fw_checksum(&init, priv, header, init.chksum);
> if (ret)
> - return ret;
> + goto release_fw;
>
> __enable_dcpu(priv);
>
> - return 0;
> +release_fw:
> + release_firmware(fw);
> + return ret;
> }
>
> static ssize_t generic_show(unsigned int command, u32 response[],
> --
> 2.28.0
>