Re: [PATCH] thermal: mtk: Allocate enough space for mtk_thermal.

From: Daniel Lezcano
Date: Wed Jan 30 2019 - 02:44:40 EST


On 30/01/2019 07:04, Peter Shih wrote:
> Adding Michael Kao to cc list.
>
> On Wed, Jan 9, 2019 at 1:57 PM Pi-Hsun Shih <pihsun@xxxxxxxxxxxx> wrote:
>>
>> The mtk_thermal struct contains a 'struct mtk_thermal_bank banks[];',
>> but the allocation only allocates sizeof(struct mtk_thermal) bytes,
>> which cause out of bound access with the ->banks[] member. Change it to
>> a fixed size array instead.

Even if the fix is correct, it pushes back the bug later in time if a
new board containing more than MAX_NUM_ZONES is introduced. I suggest to
dynamically allocate the array with the 'num_banks' value.


>> Signed-off-by: Pi-Hsun Shih <pihsun@xxxxxxxxxxxx>
>> ---
>> drivers/thermal/mtk_thermal.c | 7 +++++--
>> 1 file changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/thermal/mtk_thermal.c b/drivers/thermal/mtk_thermal.c
>> index 0691f260f6eabe..ea11edb3fcced6 100644
>> --- a/drivers/thermal/mtk_thermal.c
>> +++ b/drivers/thermal/mtk_thermal.c
>> @@ -159,6 +159,9 @@
>> #define MT7622_NUM_SENSORS_PER_ZONE 1
>> #define MT7622_TS1 0
>>
>> +/* The maximum number of banks */
>> +#define MAX_NUM_ZONES 8
>> +
>> struct mtk_thermal;
>>
>> struct thermal_bank_cfg {
>> @@ -178,7 +181,7 @@ struct mtk_thermal_data {
>> const int *sensor_mux_values;
>> const int *msr;
>> const int *adcpnp;
>> - struct thermal_bank_cfg bank_data[];
>> + struct thermal_bank_cfg bank_data[MAX_NUM_ZONES];
>> };
>>
>> struct mtk_thermal {
>> @@ -197,7 +200,7 @@ struct mtk_thermal {
>> s32 vts[MT8173_NUM_SENSORS];
>>
>> const struct mtk_thermal_data *conf;
>> - struct mtk_thermal_bank banks[];
>> + struct mtk_thermal_bank banks[MAX_NUM_ZONES];
>> };
>>
>> /* MT8173 thermal sensor data */
>> --
>> 2.20.1.97.g81188d93c3-goog
>>


--
<http://www.linaro.org/> Linaro.org â Open source software for ARM SoCs

Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog