Re: [PATCH] rtlwifi: Fix PCI probe error path orphaned memory

[Larry Finger <Larry.Finger@lwfinger.net>]

On 02/02/2012 02:48 PM, Tim Gardner wrote:
> Memory allocated by ieee80211_alloc_hw() will get orphaned
> if any subsequent initializations fail.
>
> Also don't pci_set_drvdata(pdev, NULL) until just before disabling
> the PCI device. Functions called by rtl_deinit_core(hw) may eventually need
> the context (when its actually implemented).
>
> Cc: Larry Finger<Larry.Finger@lwfinger.net>
> Cc: Chaoming Li<chaoming_li@realsil.com.cn>
> Cc: John W. Linville<linville@tuxdriver.com>
> Cc: linux-wireless@vger.kernel.org
> Cc: netdev@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Tim Gardner<tim.gardner@canonical.com>
> ---
>   drivers/net/wireless/rtlwifi/pci.c |   19 ++++++++++++-------
>   1 files changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/wireless/rtlwifi/pci.c b/drivers/net/wireless/rtlwifi/pci.c
> index 5cb2199..6b18063 100644
> --- a/drivers/net/wireless/rtlwifi/pci.c
> +++ b/drivers/net/wireless/rtlwifi/pci.c
> @@ -1760,8 +1760,8 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
>   		if (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32))) {
>   			RT_ASSERT(false,
>   				  "Unable to obtain 32bit DMA for consistent allocations\n");
> -			pci_disable_device(pdev);
> -			return -ENOMEM;
> +			err = -ENOMEM;
> +			goto fail1;

I would probably added a new label after the ieee80211_free_hw() and used it 
here to avoid the "if (hw)" test, but that is a matter of choice. In any case 
this patch is correct.

ACKed-by: Larry Finger <Larry.Finger@lwfinger.net>

Thanks,

Larry

>   		}
>   	}
>
> @@ -1803,7 +1803,7 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
>   	err = pci_request_regions(pdev, KBUILD_MODNAME);
>   	if (err) {
>   		RT_ASSERT(false, "Can't obtain PCI resources\n");
> -		goto fail2;
> +		goto fail1;
>   	}
>
>   	pmem_start = pci_resource_start(pdev, rtlpriv->cfg->bar_id);
> @@ -1816,6 +1816,7 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
>   			rtlpriv->cfg->bar_id, pmem_len);
>   	if (rtlpriv->io.pci_mem_start == 0) {
>   		RT_ASSERT(false, "Can't map PCI mem\n");
> +		err = -ENOMEM;
>   		goto fail2;
>   	}
>
> @@ -1832,8 +1833,10 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
>   	pci_write_config_byte(pdev, 0x04, 0x07);
>
>   	/* find adapter */
> -	if (!_rtl_pci_find_adapter(pdev, hw))
> +	if (!_rtl_pci_find_adapter(pdev, hw)) {
> +		err = -ENODEV;
>   		goto fail3;
> +	}
>
>   	/* Init IO handler */
>   	_rtl_pci_io_handler_init(&pdev->dev, hw);
> @@ -1843,6 +1846,7 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
>
>   	if (rtlpriv->cfg->ops->init_sw_vars(hw)) {
>   		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG, "Can't init_sw_vars\n");
> +		err = -ENODEV;
>   		goto fail3;
>   	}
>
> @@ -1887,7 +1891,6 @@ int __devinit rtl_pci_probe(struct pci_dev *pdev,
>   	return 0;
>
>   fail3:
> -	pci_set_drvdata(pdev, NULL);
>   	rtl_deinit_core(hw);
>   	_rtl_pci_io_handler_release(hw);
>
> @@ -1899,10 +1902,12 @@ fail2:
>   	complete(&rtlpriv->firmware_loading_complete);
>
>   fail1:
> -
> +	if (hw)
> +		ieee80211_free_hw(hw);
> +	pci_set_drvdata(pdev, NULL);
>   	pci_disable_device(pdev);
>
> -	return -ENODEV;
> +	return err;
>
>   }
>   EXPORT_SYMBOL(rtl_pci_probe);