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From:   Alex Dewar <alex.dewar90@gmail.com>
Date:   Thu, 20 Aug 2020 18:08:35 +0100
To:     Krzysztof Kozlowski <krzk@kernel.org>
Cc:     Alex Dewar <alex.dewar90@gmail.com>,
        Markus Mayer <mmayer@broadcom.com>,
        bcm-kernel-feedback-list@broadcom.com,
        Florian Fainelli <f.fainelli@gmail.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] memory: brcmstb_dpfe: Fix memory leak
Message-ID: <20200820170835.eos4mia5aokkikog@medion>
References: <20200818110201.69933-1-alex.dewar90@gmail.com>
 <20200820152944.GB17144@kozik-lap>
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On Thu, Aug 20, 2020 at 05:29:44PM +0200, Krzysztof Kozlowski wrote:
> 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@gmail.com>
> > ---
> >  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

Good spot! I'll send a v2.

> 
> >  
> >  	/*
> >  	 * 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
> >