| Message ID | 1630715659-5058-1-git-send-email-quic_subbaram@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | thermal: Fix a NULL pointer dereference | expand |
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: stable@vger.kernel.org >> Suggested-by: David Collins <quic_collinsd@quicinc.com> >> Signed-off-by: Subbaraman Narayanamurthy <quic_subbaram@quicinc.com> >> --- >> 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
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);
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: stable@vger.kernel.org Suggested-by: David Collins <quic_collinsd@quicinc.com> Signed-off-by: Subbaraman Narayanamurthy <quic_subbaram@quicinc.com> --- drivers/thermal/thermal_of.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)