2023-07-13 10:31:18

by Russell King (Oracle)

Subject: Re: Fwd: [PATCH] arm: mm: replace snprintf in show functions with sysfs_emit

On Thu, Jul 13, 2023 at 06:06:15PM +0800, [email protected] wrote:
> coccicheck complains about the use of snprintf() in sysfs show functions.
>
> Fix the coccicheck warning:
> WARNING: use scnprintf or sprintf.
>
> ./arch/arm/mm/cache-l2x0-pmu.c:346:8-16: WARNING: use scnprintf or sprintf
>
> Signed-off-by: ztt <[email protected]>
> ---
> arch/arm/mm/cache-l2x0-pmu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm/mm/cache-l2x0-pmu.c b/arch/arm/mm/cache-l2x0-pmu.c
> index 993fefdc167a..d20626451a2e 100644
> --- a/arch/arm/mm/cache-l2x0-pmu.c
> +++ b/arch/arm/mm/cache-l2x0-pmu.c
> @@ -343,7 +343,7 @@ static ssize_t l2x0_pmu_event_show(struct device *dev,
> struct l2x0_event_attribute *lattr;
>
> lattr = container_of(attr, typeof(*lattr), attr);
> - return snprintf(buf, PAGE_SIZE, "config=0x%x\n", lattr->config);
> + return scnprintf(buf, PAGE_SIZE, "config=0x%x\n", lattr->config);

This only serves to shut up a warning. On 32-bit ARM, there is utterly
no way what so ever that "config=0x%x\n" could ever overflow 4096 bytes,
or even 32 bytes!

--
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2023-07-17 08:49:16

by David Laight

Subject: RE: Fwd: [PATCH] arm: mm: replace snprintf in show functions with sysfs_emit

From: Russell King <[email protected]>
> Sent: 13 July 2023 11:16
> To: [email protected]
> Cc: [email protected]; [email protected]
> Subject: Re: Fwd: [PATCH] arm: mm: replace snprintf in show functions with sysfs_emit
>
> On Thu, Jul 13, 2023 at 06:06:15PM +0800, [email protected] wrote:
> > coccicheck complains about the use of snprintf() in sysfs show functions.
> >
> > Fix the coccicheck warning:
> > WARNING: use scnprintf or sprintf.
> >
> > ./arch/arm/mm/cache-l2x0-pmu.c:346:8-16: WARNING: use scnprintf or sprintf
> >
> > Signed-off-by: ztt <[email protected]>
> > ---
> > arch/arm/mm/cache-l2x0-pmu.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/mm/cache-l2x0-pmu.c b/arch/arm/mm/cache-l2x0-pmu.c
> > index 993fefdc167a..d20626451a2e 100644
> > --- a/arch/arm/mm/cache-l2x0-pmu.c
> > +++ b/arch/arm/mm/cache-l2x0-pmu.c
> > @@ -343,7 +343,7 @@ static ssize_t l2x0_pmu_event_show(struct device *dev,
> > struct l2x0_event_attribute *lattr;
> >
> > lattr = container_of(attr, typeof(*lattr), attr);
> > - return snprintf(buf, PAGE_SIZE, "config=0x%x\n", lattr->config);
> > + return scnprintf(buf, PAGE_SIZE, "config=0x%x\n", lattr->config);
>
> This only serves to shut up a warning. On 32-bit ARM, there is utterly
> no way what so ever that "config=0x%x\n" could ever overflow 4096 bytes,
> or even 32 bytes!

The code also doesn't match the commit message.
Did you actually send the correct copy of all these patches?

David

-
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