Re: [PATCH][V3] usb: ohci-da8xx: ensure error return on variable error is set

From: Alan Stern
Date: Tue Jan 07 2020 - 14:47:46 EST


On Tue, 7 Jan 2020, Colin King wrote:

> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Currently when an error occurs when calling devm_gpiod_get_optional or
> calling gpiod_to_irq it causes an uninitialized error return in variable
> 'error' to be returned. Fix this by ensuring the error variable is set
> from da8xx_ohci->oc_gpio and oc_irq.
>
> Thanks to Dan Carpenter for spotting the uninitialized error in the
> gpiod_to_irq failure case.
>
> Addresses-Coverity: ("Uninitialized scalar variable")
> Fixes: d193abf1c913 ("usb: ohci-da8xx: add vbus and overcurrent gpios")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
>
> V2: fix typo and grammar in commit message
> V3: fix gpiod_to_irq error case, re-write commit message
>
> ---
> drivers/usb/host/ohci-da8xx.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/host/ohci-da8xx.c b/drivers/usb/host/ohci-da8xx.c
> index 38183ac438c6..1371b0c249ec 100644
> --- a/drivers/usb/host/ohci-da8xx.c
> +++ b/drivers/usb/host/ohci-da8xx.c
> @@ -415,13 +415,17 @@ static int ohci_da8xx_probe(struct platform_device *pdev)
> }
>
> da8xx_ohci->oc_gpio = devm_gpiod_get_optional(dev, "oc", GPIOD_IN);
> - if (IS_ERR(da8xx_ohci->oc_gpio))
> + if (IS_ERR(da8xx_ohci->oc_gpio)) {
> + error = PTR_ERR(da8xx_ohci->oc_gpio);
> goto err;
> + }
>
> if (da8xx_ohci->oc_gpio) {
> oc_irq = gpiod_to_irq(da8xx_ohci->oc_gpio);
> - if (oc_irq < 0)
> + if (oc_irq < 0) {
> + error = oc_irq;
> goto err;
> + }
>
> error = devm_request_threaded_irq(dev, oc_irq, NULL,
> ohci_da8xx_oc_thread, IRQF_TRIGGER_RISING |

Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>