Patch "thermal/core: Fix null pointer dereference in thermal_release()" has been added to the 5.14-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    thermal/core: Fix null pointer dereference in thermal_release()

to the 5.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     thermal-core-fix-null-pointer-dereference-in-thermal.patch
and it can be found in the queue-5.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b8b5b1422a5254e9256632e84b4dbe964c3a34e1
Author: Yuanzheng Song <songyuanzheng@xxxxxxxxxx>
Date:   Fri Oct 15 08:32:30 2021 +0000

    thermal/core: Fix null pointer dereference in thermal_release()
    
    [ Upstream commit 1dd7128b839f631b31a9e9dce3aaf639bef74e9d ]
    
    If both dev_set_name() and device_register() failed, then null pointer
    dereference occurs in thermal_release() which will use strncmp() to
    compare the name.
    
    So fix it by adding dev_set_name() return value check.
    
    Signed-off-by: Yuanzheng Song <songyuanzheng@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20211015083230.67658-1-songyuanzheng@xxxxxxxxxx
    Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 51374f4e1ccaf..d094ebbde0ed7 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -902,6 +902,10 @@ __thermal_cooling_device_register(struct device_node *np,
 		goto out_kfree_cdev;
 	cdev->id = ret;
 
+	ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
+	if (ret)
+		goto out_ida_remove;
+
 	cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
 	if (!cdev->type) {
 		ret = -ENOMEM;
@@ -916,7 +920,6 @@ __thermal_cooling_device_register(struct device_node *np,
 	cdev->device.class = &thermal_class;
 	cdev->devdata = devdata;
 	thermal_cooling_device_setup_sysfs(cdev);
-	dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 	ret = device_register(&cdev->device);
 	if (ret)
 		goto out_kfree_type;
@@ -1227,6 +1230,10 @@ thermal_zone_device_register(const char *type, int trips, int mask,
 	tz->id = id;
 	strlcpy(tz->type, type, sizeof(tz->type));
 
+	result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
+	if (result)
+		goto remove_id;
+
 	if (!ops->critical)
 		ops->critical = thermal_zone_device_critical;
 
@@ -1248,7 +1255,6 @@ thermal_zone_device_register(const char *type, int trips, int mask,
 	/* A new thermal zone needs to be updated anyway. */
 	atomic_set(&tz->need_update, 1);
 
-	dev_set_name(&tz->device, "thermal_zone%d", tz->id);
 	result = device_register(&tz->device);
 	if (result)
 		goto release_device;