From 6a315471cb6a07f651e1d3adc8962730f4fcccac Mon Sep 17 00:00:00 2001 From: Subbaraman Narayanamurthy Date: Thu, 4 Nov 2021 16:57:07 -0700 Subject: [PATCH] thermal: Fix NULL pointer dereferences in of_thermal_ functions commit 96cfe05051fd8543cdedd6807ec59a0e6c409195 upstream. 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 While at it, fix the possible NULL pointer dereference in other functions as well: of_thermal_get_temp(), of_thermal_set_emul_temp(), of_thermal_get_trend(). Suggested-by: David Collins Signed-off-by: Subbaraman Narayanamurthy Acked-by: Daniel Lezcano Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/thermal/thermal_of.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c index 6379f26..9233f7e 100644 --- a/drivers/thermal/thermal_of.c +++ b/drivers/thermal/thermal_of.c @@ -89,7 +89,7 @@ static int of_thermal_get_temp(struct thermal_zone_device *tz, { struct __thermal_zone *data = tz->devdata; - if (!data->ops->get_temp) + if (!data->ops || !data->ops->get_temp) return -EINVAL; return data->ops->get_temp(data->sensor_data, temp); @@ -186,6 +186,9 @@ static int of_thermal_set_emul_temp(struct thermal_zone_device *tz, { struct __thermal_zone *data = tz->devdata; + if (!data->ops || !data->ops->set_emul_temp) + return -EINVAL; + return data->ops->set_emul_temp(data->sensor_data, temp); } @@ -194,7 +197,7 @@ static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip, { struct __thermal_zone *data = tz->devdata; - if (!data->ops->get_trend) + if (!data->ops || !data->ops->get_trend) return -EINVAL; return data->ops->get_trend(data->sensor_data, trip, trend); @@ -301,7 +304,7 @@ 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