From 44303170c31f69788937fd972ca2a1ea04e3e9c0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 3 Oct 2024 14:25:58 +0200 Subject: [PATCH] thermal: core: Reference count the zone in thermal_zone_get_by_id() BugLink: https://bugs.launchpad.net/bugs/2097301 commit a42a5839f400e929c489bb1b58f54596c4535167 upstream. There are places in the thermal netlink code where nothing prevents the thermal zone object from going away while being accessed after it has been returned by thermal_zone_get_by_id(). To address this, make thermal_zone_get_by_id() get a reference on the thermal zone device object to be returned with the help of get_device(), under thermal_list_lock, and adjust all of its callers to this change with the help of the cleanup.h infrastructure. Fixes: 1ce50e7d408e ("thermal: core: genetlink support for events/cmd/sampling") Cc: 6.8+ # 6.8+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Lukasz Luba Link: https://patch.msgid.link/6112242.lOV4Wx5bFT@rjwysocki.net Signed-off-by: Greg Kroah-Hartman CVE-2024-50028 Signed-off-by: Manuel Diewald Signed-off-by: Koichiro Den --- drivers/thermal/thermal_core.c | 1 + drivers/thermal/thermal_core.h | 3 +++ drivers/thermal/thermal_netlink.c | 9 +++------ 3 files changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index d9d075bc5549..e689faab81fd 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -625,6 +625,7 @@ struct thermal_zone_device *thermal_zone_get_by_id(int id) mutex_lock(&thermal_list_lock); list_for_each_entry(tz, &thermal_tz_list, node) { if (tz->id == id) { + get_device(&tz->device); match = tz; break; } diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index e9c099ecdd0f..8963833de31c 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -57,6 +57,9 @@ int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *), struct thermal_zone_device *thermal_zone_get_by_id(int id); +DEFINE_CLASS(thermal_zone_get_by_id, struct thermal_zone_device *, + if (_T) put_device(&_T->device), thermal_zone_get_by_id(id), int id) + struct thermal_attr { struct device_attribute attr; char name[THERMAL_NAME_LENGTH]; diff --git a/drivers/thermal/thermal_netlink.c b/drivers/thermal/thermal_netlink.c index 76a231a29654..8e9d84723b36 100644 --- a/drivers/thermal/thermal_netlink.c +++ b/drivers/thermal/thermal_netlink.c @@ -446,7 +446,6 @@ static int thermal_genl_cmd_tz_get_trip(struct param *p) { struct sk_buff *msg = p->msg; const struct thermal_trip *trip; - struct thermal_zone_device *tz; struct nlattr *start_trip; int id; @@ -455,7 +454,7 @@ static int thermal_genl_cmd_tz_get_trip(struct param *p) id = nla_get_u32(p->attrs[THERMAL_GENL_ATTR_TZ_ID]); - tz = thermal_zone_get_by_id(id); + CLASS(thermal_zone_get_by_id, tz)(id); if (!tz) return -EINVAL; @@ -489,7 +488,6 @@ out_cancel_nest: static int thermal_genl_cmd_tz_get_temp(struct param *p) { struct sk_buff *msg = p->msg; - struct thermal_zone_device *tz; int temp, ret, id; if (!p->attrs[THERMAL_GENL_ATTR_TZ_ID]) @@ -497,7 +495,7 @@ static int thermal_genl_cmd_tz_get_temp(struct param *p) id = nla_get_u32(p->attrs[THERMAL_GENL_ATTR_TZ_ID]); - tz = thermal_zone_get_by_id(id); + CLASS(thermal_zone_get_by_id, tz)(id); if (!tz) return -EINVAL; @@ -515,7 +513,6 @@ static int thermal_genl_cmd_tz_get_temp(struct param *p) static int thermal_genl_cmd_tz_get_gov(struct param *p) { struct sk_buff *msg = p->msg; - struct thermal_zone_device *tz; int id, ret = 0; if (!p->attrs[THERMAL_GENL_ATTR_TZ_ID]) @@ -523,7 +520,7 @@ static int thermal_genl_cmd_tz_get_gov(struct param *p) id = nla_get_u32(p->attrs[THERMAL_GENL_ATTR_TZ_ID]); - tz = thermal_zone_get_by_id(id); + CLASS(thermal_zone_get_by_id, tz)(id); if (!tz) return -EINVAL;