[PATCH] PM / Domains: check for negative return from of_count_phandle_with_args

[PATCH] PM / Domains: check for negative return from of_count_phandle_with_args

[Colin King]

From: Colin Ian King <colin.king@canonical.com>

The return from of_count_phandle_with_args can be negative, so we
should avoid kcalloc of a negative count of genpd_power_stat structs
by sanity checking if count is zero or less.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/base/power/domain.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index aac656a..661737c 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2113,7 +2113,7 @@ int of_genpd_parse_idle_states(struct device_node *dn,
 	struct of_phandle_iterator it;
 
 	count = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
-	if (!count)
+	if (count <= 0)
 		return -EINVAL;
 
 	st = kcalloc(count, sizeof(*st), GFP_KERNEL);
-- 
2.9.3

Re: [PATCH] PM / Domains: check for negative return from of_count_phandle_with_args

[Kevin Hilman]

Colin King <colin.king@canonical.com> writes:

> From: Colin Ian King <colin.king@canonical.com>
>
> The return from of_count_phandle_with_args can be negative, so we
> should avoid kcalloc of a negative count of genpd_power_stat structs
> by sanity checking if count is zero or less.
>
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Acked-by: Kevin Hilman <khilman@baylibre.com>

> ---
>  drivers/base/power/domain.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index aac656a..661737c 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2113,7 +2113,7 @@ int of_genpd_parse_idle_states(struct device_node *dn,
>  	struct of_phandle_iterator it;
>  
>  	count = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
> -	if (!count)
> +	if (count <= 0)
>  		return -EINVAL;
>  
>  	st = kcalloc(count, sizeof(*st), GFP_KERNEL);

Re: [PATCH] PM / Domains: check for negative return from of_count_phandle_with_args

[Pavel Machek]

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On Tue 2016-10-25 11:14:40, Kevin Hilman wrote:
> Colin King <colin.king@canonical.com> writes:
> 
> > From: Colin Ian King <colin.king@canonical.com>
> >
> > The return from of_count_phandle_with_args can be negative, so we
> > should avoid kcalloc of a negative count of genpd_power_stat structs
> > by sanity checking if count is zero or less.
> >
> > Signed-off-by: Colin Ian King <colin.king@canonical.com>
> 
> Acked-by: Kevin Hilman <khilman@baylibre.com>

Acked-by: Pavel Machek <pavel@ucw.cz>

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH] PM / Domains: check for negative return from of_count_phandle_with_args

[Rafael J. Wysocki]

On Wednesday, October 26, 2016 01:00:08 PM Pavel Machek wrote:
> 
> --zhXaljGHf11kAtnf
> Content-Type: text/plain; charset=us-ascii
> Content-Disposition: inline
> Content-Transfer-Encoding: quoted-printable
> 
> On Tue 2016-10-25 11:14:40, Kevin Hilman wrote:
> > Colin King <colin.king@canonical.com> writes:
> >=20
> > > From: Colin Ian King <colin.king@canonical.com>
> > >
> > > The return from of_count_phandle_with_args can be negative, so we
> > > should avoid kcalloc of a negative count of genpd_power_stat structs
> > > by sanity checking if count is zero or less.
> > >
> > > Signed-off-by: Colin Ian King <colin.king@canonical.com>
> >=20
> > Acked-by: Kevin Hilman <khilman@baylibre.com>
> 
> Acked-by: Pavel Machek <pavel@ucw.cz>

Applied, thanks!

Rafael