From: Subbaraman Narayanamurthy quic_subbaram@quicinc.com

stable inclusion from stable-v5.10.81 commit 6a315471cb6a07f651e1d3adc8962730f4fcccac category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9FNF5 CVE: CVE-2021-47202

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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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 quic_collinsd@quicinc.com Signed-off-by: Subbaraman Narayanamurthy quic_subbaram@quicinc.com Acked-by: Daniel Lezcano daniel.lezcano@linaro.org Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Conflicts: drivers/thermal/of-thermal.c Signed-off-by: Liu Mingrui liumingrui@huawei.com --- drivers/thermal/of-thermal.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c index 4f2816559205..856dce4d72e2 100644 --- a/drivers/thermal/of-thermal.c +++ b/drivers/thermal/of-thermal.c @@ -77,7 +77,7 @@ 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); @@ -174,6 +174,10 @@ 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); }

@@ -182,7 +186,7 @@ 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); @@ -310,7 +314,7 @@ 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);