Re: [PATCH] acpi_system_write_wakeup_device(): fix error check for unsigned variable.

From: Rafael J. Wysocki
Date: Tue Nov 20 2012 - 19:40:21 EST


On Saturday, November 17, 2012 02:54:23 AM Cyril Roelandt wrote:
> The LEN variable is unsigned, therefore checking whether it is less than 0 is
> useless.
>
> Signed-off-by: Cyril Roelandt <tipecaml@xxxxxxxxx>
> ---
> drivers/acpi/proc.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/drivers/acpi/proc.c b/drivers/acpi/proc.c
> index 27adb09..37871a7 100644
> --- a/drivers/acpi/proc.c
> +++ b/drivers/acpi/proc.c
> @@ -366,8 +366,6 @@ acpi_system_write_wakeup_device(struct file *file,
>
> if (len > 4)
> len = 4;
> - if (len < 0)
> - return -EFAULT;

I would prefer to check if count < 0 instead.

>
> if (copy_from_user(strbuf, buffer, len))
> return -EFAULT;

Thanks,
Rafael


--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/