of_parse_thermal_zones() parses the thermal-zones node and registers a
thermal_zone device for each subnode. However, if a thermal zone is
consuming a thermal sensor and that thermal sensor device hasn't probed
yet, an attempt to set trip_point_*_temp for that thermal zone device
can cause a NULL pointer dereference. Fix it.
console:/sys/class/thermal/thermal_zone87 # echo 120000 > trip_point_0_temp
...
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
...
Call trace:
of_thermal_set_trip_temp+0x40/0xc4
trip_point_temp_store+0xc0/0x1dc
dev_attr_store+0x38/0x88
sysfs_kf_write+0x64/0xc0
kernfs_fop_write_iter+0x108/0x1d0
vfs_write+0x2f4/0x368
ksys_write+0x7c/0xec
__arm64_sys_write+0x20/0x30
el0_svc_common.llvm.7279915941325364641+0xbc/0x1bc
do_el0_svc+0x28/0xa0
el0_svc+0x14/0x24
el0_sync_handler+0x88/0xec
el0_sync+0x1c0/0x200
Cc: [email protected]
Suggested-by: David Collins <[email protected]>
Signed-off-by: Subbaraman Narayanamurthy <[email protected]>
---
drivers/thermal/thermal_of.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
index 6379f26..ba53252 100644
--- a/drivers/thermal/thermal_of.c
+++ b/drivers/thermal/thermal_of.c
@@ -301,7 +301,7 @@ static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
if (trip >= data->ntrips || trip < 0)
return -EDOM;
- if (data->ops->set_trip_temp) {
+ if (data->ops && data->ops->set_trip_temp) {
int ret;
ret = data->ops->set_trip_temp(data->sensor_data, trip, temp);
--
2.7.4
On 9/3/21 5:34 PM, Subbaraman Narayanamurthy wrote:
> of_parse_thermal_zones() parses the thermal-zones node and registers a
> thermal_zone device for each subnode. However, if a thermal zone is
> consuming a thermal sensor and that thermal sensor device hasn't probed
> yet, an attempt to set trip_point_*_temp for that thermal zone device
> can cause a NULL pointer dereference. Fix it.
>
> console:/sys/class/thermal/thermal_zone87 # echo 120000 > trip_point_0_temp
> ...
> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
> ...
> Call trace:
> of_thermal_set_trip_temp+0x40/0xc4
> trip_point_temp_store+0xc0/0x1dc
> dev_attr_store+0x38/0x88
> sysfs_kf_write+0x64/0xc0
> kernfs_fop_write_iter+0x108/0x1d0
> vfs_write+0x2f4/0x368
> ksys_write+0x7c/0xec
> __arm64_sys_write+0x20/0x30
> el0_svc_common.llvm.7279915941325364641+0xbc/0x1bc
> do_el0_svc+0x28/0xa0
> el0_svc+0x14/0x24
> el0_sync_handler+0x88/0xec
> el0_sync+0x1c0/0x200
>
> Cc: [email protected]
> Suggested-by: David Collins <[email protected]>
> Signed-off-by: Subbaraman Narayanamurthy <[email protected]>
> ---
> drivers/thermal/thermal_of.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
> index 6379f26..ba53252 100644
> --- a/drivers/thermal/thermal_of.c
> +++ b/drivers/thermal/thermal_of.c
> @@ -301,7 +301,7 @@ static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
> if (trip >= data->ntrips || trip < 0)
> return -EDOM;
>
> - if (data->ops->set_trip_temp) {
> + if (data->ops && data->ops->set_trip_temp) {
> int ret;
>
> ret = data->ops->set_trip_temp(data->sensor_data, trip, temp);
>
It looks like the same kind of data->ops null pointer dereference issue is
present in three other functions within this file: of_thermal_get_temp(),
of_thermal_set_emul_temp(), and of_thermal_get_trend(). Should those be
fixed along with of_thermal_set_trip_temp() in a single patch?
Thanks,
David
On 9/3/21 6:07 PM, David Collins wrote:
> On 9/3/21 5:34 PM, Subbaraman Narayanamurthy wrote:
>> of_parse_thermal_zones() parses the thermal-zones node and registers a
>> thermal_zone device for each subnode. However, if a thermal zone is
>> consuming a thermal sensor and that thermal sensor device hasn't probed
>> yet, an attempt to set trip_point_*_temp for that thermal zone device
>> can cause a NULL pointer dereference. Fix it.
>>
>> console:/sys/class/thermal/thermal_zone87 # echo 120000 > trip_point_0_temp
>> ...
>> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
>> ...
>> Call trace:
>> of_thermal_set_trip_temp+0x40/0xc4
>> trip_point_temp_store+0xc0/0x1dc
>> dev_attr_store+0x38/0x88
>> sysfs_kf_write+0x64/0xc0
>> kernfs_fop_write_iter+0x108/0x1d0
>> vfs_write+0x2f4/0x368
>> ksys_write+0x7c/0xec
>> __arm64_sys_write+0x20/0x30
>> el0_svc_common.llvm.7279915941325364641+0xbc/0x1bc
>> do_el0_svc+0x28/0xa0
>> el0_svc+0x14/0x24
>> el0_sync_handler+0x88/0xec
>> el0_sync+0x1c0/0x200
>>
>> Cc: [email protected]
>> Suggested-by: David Collins <[email protected]>
>> Signed-off-by: Subbaraman Narayanamurthy <[email protected]>
>> ---
>> drivers/thermal/thermal_of.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
>> index 6379f26..ba53252 100644
>> --- a/drivers/thermal/thermal_of.c
>> +++ b/drivers/thermal/thermal_of.c
>> @@ -301,7 +301,7 @@ static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
>> if (trip >= data->ntrips || trip < 0)
>> return -EDOM;
>> - if (data->ops->set_trip_temp) {
>> + if (data->ops && data->ops->set_trip_temp) {
>> int ret;
>> ret = data->ops->set_trip_temp(data->sensor_data, trip, temp);
>>
>
> It looks like the same kind of data->ops null pointer dereference issue is present in three other functions within this file: of_thermal_get_temp(), of_thermal_set_emul_temp(), and of_thermal_get_trend(). Should those be fixed along with of_thermal_set_trip_temp() in a single patch?
Sure, I can make those changes in this patch itself.
>
> Thanks,
> David