Re: [PATCH v2] thermal: ti-soc-thermal: avoid dereferencing ERR_PTR

From: Amit Kucheria
Date: Tue Apr 28 2020 - 16:34:12 EST


On Fri, Apr 24, 2020 at 9:49 PM Sudip Mukherjee
<sudipm.mukherjee@xxxxxxxxx> wrote:
>
> On error the function ti_bandgap_get_sensor_data() returns the error
> code in ERR_PTR() but we only checked if the return value is NULL or
> not. And, so we can dereference an error code inside ERR_PTR.
> While at it, convert a check to IS_ERR_OR_NULL.
>
> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>
Reviewed-by: Amit Kucheria <amit.kucheria@xxxxxxxxxx>

> ---
> drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
> index d3e959d01606..85776db4bf34 100644
> --- a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
> +++ b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
> @@ -169,7 +169,7 @@ int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id,
>
> data = ti_bandgap_get_sensor_data(bgp, id);
>
> - if (!data || IS_ERR(data))
> + if (!IS_ERR_OR_NULL(data))
> data = ti_thermal_build_data(bgp, id);
>
> if (!data)
> @@ -196,7 +196,7 @@ int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id)
>
> data = ti_bandgap_get_sensor_data(bgp, id);
>
> - if (data && data->ti_thermal) {
> + if (!IS_ERR_OR_NULL(data) && data->ti_thermal) {
> if (data->our_zone)
> thermal_zone_device_unregister(data->ti_thermal);
> }
> @@ -262,7 +262,7 @@ int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id)
>
> data = ti_bandgap_get_sensor_data(bgp, id);
>
> - if (data) {
> + if (!IS_ERR_OR_NULL(data)) {
> cpufreq_cooling_unregister(data->cool_dev);
> if (data->policy)
> cpufreq_cpu_put(data->policy);
> --
> 2.11.0
>