2020-04-26 20:27:31

by Christophe JAILLET

Subject: [PATCH] mmc: alcor: Fix a resource leak in an error handling path in 'alcor_pci_sdmmc_drv_probe()'

If 'devm_request_threaded_irq()' fails, resources allocated by
'mmc_alloc_host()' must be freed.

Fixes: c5413ad815a6 ("mmc: add new Alcor Micro Cardreader SD/MMC driver")
Signed-off-by: Christophe JAILLET <[email protected]>
---
drivers/mmc/host/alcor.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/alcor.c b/drivers/mmc/host/alcor.c
index 1aee485d56d4..026ca9194ce5 100644
--- a/drivers/mmc/host/alcor.c
+++ b/drivers/mmc/host/alcor.c
@@ -1104,7 +1104,7 @@ static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)

if (ret) {
dev_err(&pdev->dev, "Failed to get irq for data line\n");
- return ret;
+ goto free_host;
}

mutex_init(&host->cmd_mutex);
@@ -1116,6 +1116,10 @@ static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)
dev_set_drvdata(&pdev->dev, host);
mmc_add_host(mmc);
return 0;
+
+free_host:
+ mmc_free_host(mmc);
+ return ret;
}

static int alcor_pci_sdmmc_drv_remove(struct platform_device *pdev)
--
2.25.1

2020-04-27 05:57:04

by Markus Elfring

Subject: Re: [PATCH] mmc: alcor: Fix a resource leak in an error handling path in 'alcor_pci_sdmmc_drv_probe()'

> If 'devm_request_threaded_irq()' fails, resources allocated by
> 'mmc_alloc_host()' must be freed.

How do you think about a wording variant like the following?

Subject:
[PATCH v2] mmc: alcor: Complete exception handling in alcor_pci_sdmmc_drv_probe()

Change description (according to a solution alternative):
The exception handling was incomplete in an if branch
after a failed call of the function “devm_request_threaded_irq”.
Thus add a call of the function “mmc_free_host” for the release of
corresponding system resources.


> +++ b/drivers/mmc/host/alcor.c
> @@ -1104,7 +1104,7 @@ static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)
>
> if (ret) {
> dev_err(&pdev->dev, "Failed to get irq for data line\n");
> - return ret;
> + goto free_host;
> }
>
> mutex_init(&host->cmd_mutex);

You propose to perform a jump to other code only once in this implementation.
I find it more succinct to call the desired function then directly.

dev_err(…);
+ mmc_free_host(mmc);
return ret;


Regards,
Markus

2020-05-05 11:35:27

by Ulf Hansson

Subject: Re: [PATCH] mmc: alcor: Fix a resource leak in an error handling path in 'alcor_pci_sdmmc_drv_probe()'

On Sun, 26 Apr 2020 at 22:23, Christophe JAILLET
<[email protected]> wrote:
>
> If 'devm_request_threaded_irq()' fails, resources allocated by
> 'mmc_alloc_host()' must be freed.
>
> Fixes: c5413ad815a6 ("mmc: add new Alcor Micro Cardreader SD/MMC driver")
> Signed-off-by: Christophe JAILLET <[email protected]>

Applied for fixes, thanks!

Kind regards
Uffe


> ---
> drivers/mmc/host/alcor.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/alcor.c b/drivers/mmc/host/alcor.c
> index 1aee485d56d4..026ca9194ce5 100644
> --- a/drivers/mmc/host/alcor.c
> +++ b/drivers/mmc/host/alcor.c
> @@ -1104,7 +1104,7 @@ static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)
>
> if (ret) {
> dev_err(&pdev->dev, "Failed to get irq for data line\n");
> - return ret;
> + goto free_host;
> }
>
> mutex_init(&host->cmd_mutex);
> @@ -1116,6 +1116,10 @@ static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)
> dev_set_drvdata(&pdev->dev, host);
> mmc_add_host(mmc);
> return 0;
> +
> +free_host:
> + mmc_free_host(mmc);
> + return ret;
> }
>
> static int alcor_pci_sdmmc_drv_remove(struct platform_device *pdev)
> --
> 2.25.1
>