2019-02-17 06:32:46

by Frank Lee

Subject: [PATCH] cpufreq: powernv: fix missing check of return value in init_powernv_pstates()

kmalloc() could fail, so insert a check of its return value. And
if it fails, returns -ENOMEM.

And remove (struct pstate_idx_revmap_data *) to fix coccinelle WARNING
by the way.

WARNING: casting value returned by memory allocation function to (struct
pstate_idx_revmap_data *) is useless.

Signed-off-by: Yangtao Li <[email protected]>
---
drivers/cpufreq/powernv-cpufreq.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 7e7ad3879c4e..d2230812fa4b 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -244,6 +244,7 @@ static int init_powernv_pstates(void)
u32 len_ids, len_freqs;
u32 pstate_min, pstate_max, pstate_nominal;
u32 pstate_turbo, pstate_ultra_turbo;
+ int rc = -ENODEV;

power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
if (!power_mgt) {
@@ -327,8 +328,11 @@ static int init_powernv_pstates(void)
powernv_freqs[i].frequency = freq * 1000; /* kHz */
powernv_freqs[i].driver_data = id & 0xFF;

- revmap_data = (struct pstate_idx_revmap_data *)
- kmalloc(sizeof(*revmap_data), GFP_KERNEL);
+ revmap_data = kmalloc(sizeof(*revmap_data), GFP_KERNEL);
+ if (!revmap_data) {
+ rc = -ENOMEM;
+ goto out;
+ }

revmap_data->pstate_id = id & 0xFF;
revmap_data->cpufreq_table_idx = i;
@@ -357,7 +361,7 @@ static int init_powernv_pstates(void)
return 0;
out:
of_node_put(power_mgt);
- return -ENODEV;
+ return rc;
}

/* Returns the CPU frequency corresponding to the pstate_id. */
--
2.17.0

2019-02-17 19:12:49

by Akshay Adiga

Subject: Re: [PATCH] cpufreq: powernv: fix missing check of return value in init_powernv_pstates()

On Sat, Feb 16, 2019 at 12:06:23PM -0500, Yangtao Li wrote:
> kmalloc() could fail, so insert a check of its return value. And
> if it fails, returns -ENOMEM.
>
> And remove (struct pstate_idx_revmap_data *) to fix coccinelle WARNING
> by the way.
>
> WARNING: casting value returned by memory allocation function to (struct
> pstate_idx_revmap_data *) is useless.
>
> Signed-off-by: Yangtao Li <[email protected]>
> ---
> drivers/cpufreq/powernv-cpufreq.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
Looks good to me. Thanks for fixing this.

2019-02-18 04:59:59

by Viresh Kumar

Subject: Re: [PATCH] cpufreq: powernv: fix missing check of return value in init_powernv_pstates()

On 16-02-19, 12:06, Yangtao Li wrote:
> kmalloc() could fail, so insert a check of its return value. And
> if it fails, returns -ENOMEM.
>
> And remove (struct pstate_idx_revmap_data *) to fix coccinelle WARNING
> by the way.
>
> WARNING: casting value returned by memory allocation function to (struct
> pstate_idx_revmap_data *) is useless.
>
> Signed-off-by: Yangtao Li <[email protected]>
> ---
> drivers/cpufreq/powernv-cpufreq.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
> index 7e7ad3879c4e..d2230812fa4b 100644
> --- a/drivers/cpufreq/powernv-cpufreq.c
> +++ b/drivers/cpufreq/powernv-cpufreq.c
> @@ -244,6 +244,7 @@ static int init_powernv_pstates(void)
> u32 len_ids, len_freqs;
> u32 pstate_min, pstate_max, pstate_nominal;
> u32 pstate_turbo, pstate_ultra_turbo;
> + int rc = -ENODEV;
>
> power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
> if (!power_mgt) {
> @@ -327,8 +328,11 @@ static int init_powernv_pstates(void)
> powernv_freqs[i].frequency = freq * 1000; /* kHz */
> powernv_freqs[i].driver_data = id & 0xFF;
>
> - revmap_data = (struct pstate_idx_revmap_data *)
> - kmalloc(sizeof(*revmap_data), GFP_KERNEL);
> + revmap_data = kmalloc(sizeof(*revmap_data), GFP_KERNEL);
> + if (!revmap_data) {
> + rc = -ENOMEM;
> + goto out;
> + }
>
> revmap_data->pstate_id = id & 0xFF;
> revmap_data->cpufreq_table_idx = i;
> @@ -357,7 +361,7 @@ static int init_powernv_pstates(void)
> return 0;
> out:
> of_node_put(power_mgt);
> - return -ENODEV;
> + return rc;
> }
>
> /* Returns the CPU frequency corresponding to the pstate_id. */

Applied. Thanks.

--
viresh