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

From: Rafael J. Wysocki
Date: Thu Nov 22 2012 - 14:49:17 EST


On Thursday, November 22, 2012 01:05:30 AM Cyril Roelandt wrote:
> On 11/21/2012 01:44 AM, Rafael J. Wysocki wrote:
> > 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.
> >
>
>
> count has type size_t, so it is also an unsigned variable. I think that
> acpi_system_write_wakeup_device really cannot be called with a "count"
> parameter that is less than 0.

OK

So I suppose we can just drop len entirely and replace it with count, right?
[And drop the < 0 check too.]

Rafael


--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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