2018-05-31 06:26:35

by Dan Carpenter

Subject: [PATCH] gpio: dwapb: fix a signedness bug handling IRQs

Smatch flags a couple bugs here:

drivers/gpio/gpio-dwapb.c:447 dwapb_configure_irqs() warn: always true condition '(pp->irq[i] >= 0) => (0-u32max >= 0)'
drivers/gpio/gpio-dwapb.c:627 dwapb_gpio_get_pdata() warn: always true condition '(pp->irq[j] >= 0) => (0-u32max >= 0)'

The problem is that we're storing error codes in pp->irq[] so it needs
to be signed for the error handling to work correctly.

Fixes: da069d5d2b81 ("gpio: dwapb: Rework support for 1 interrupt per port A GPIO")
Signed-off-by: Dan Carpenter <[email protected]>

diff --git a/include/linux/platform_data/gpio-dwapb.h b/include/linux/platform_data/gpio-dwapb.h
index 5a52d69c13f3..419cfacb4b42 100644
--- a/include/linux/platform_data/gpio-dwapb.h
+++ b/include/linux/platform_data/gpio-dwapb.h
@@ -19,7 +19,7 @@ struct dwapb_port_property {
unsigned int idx;
unsigned int ngpio;
unsigned int gpio_base;
- unsigned int irq[32];
+ int irq[32];
bool has_irq;
bool irq_shared;
};

2018-05-31 14:49:35

by Phil Edworthy

Subject: RE: [PATCH] gpio: dwapb: fix a signedness bug handling IRQs

Hi Dan,

On 31 May 2018 07:24 Dan Carpenter wrote:
> Smatch flags a couple bugs here:
>
> drivers/gpio/gpio-dwapb.c:447 dwapb_configure_irqs() warn: always true
> condition '(pp->irq[i] >= 0) => (0-u32max >= 0)'
> drivers/gpio/gpio-dwapb.c:627 dwapb_gpio_get_pdata() warn: always true
> condition '(pp->irq[j] >= 0) => (0-u32max >= 0)'
>
> The problem is that we're storing error codes in pp->irq[] so it needs to be
> signed for the error handling to work correctly.
>
> Fixes: da069d5d2b81 ("gpio: dwapb: Rework support for 1 interrupt per port
> A GPIO")
> Signed-off-by: Dan Carpenter <[email protected]>

Thanks for the patch, I had already noticed the mistake and sent a patch.

Thanks
Phil

> diff --git a/include/linux/platform_data/gpio-dwapb.h
> b/include/linux/platform_data/gpio-dwapb.h
> index 5a52d69c13f3..419cfacb4b42 100644
> --- a/include/linux/platform_data/gpio-dwapb.h
> +++ b/include/linux/platform_data/gpio-dwapb.h
> @@ -19,7 +19,7 @@ struct dwapb_port_property {
> unsigned int idx;
> unsigned int ngpio;
> unsigned int gpio_base;
> - unsigned int irq[32];
> + int irq[32];
> bool has_irq;
> bool irq_shared;
> };