ACPI: MRRM: Fix memory leaks and improve error handling

Add proper error handling and resource cleanup to prevent memory leaks
in add_boot_memory_ranges(). The function now checks for NULL return
from kobject_create_and_add(), uses local buffer for range names to
avoid dynamic allocation, and implements a cleanup path that removes
previously created sysfs groups and kobjects on failure.

This prevents resource leaks when kobject creation or sysfs group
creation fails during boot memory range initialization.

Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20251030023228.3956296-1-kaushlendra.kumar@intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/acpi_mrrm.c b/drivers/acpi/acpi_mrrm.c
index a6dbf623e5571fa9c8b45f9cb5c47b328a31ed48..6d69554c940ed2ca28d8029e0077dc5eef20371b 100644 (file)
--- a/drivers/acpi/acpi_mrrm.c
+++ b/drivers/acpi/acpi_mrrm.c
@@ -152,26 +152,49 @@ ATTRIBUTE_GROUPS(memory_range);
 
 static __init int add_boot_memory_ranges(void)
 {
-       struct kobject *pkobj, *kobj;
+       struct kobject *pkobj, *kobj, **kobjs;
        int ret = -EINVAL;
-       char *name;
+       char name[16];
+       int i;
 
        pkobj = kobject_create_and_add("memory_ranges", acpi_kobj);
+       if (!pkobj)
+               return -ENOMEM;
 
-       for (int i = 0; i < mrrm_mem_entry_num; i++) {
-               name = kasprintf(GFP_KERNEL, "range%d", i);
-               if (!name) {
-                       ret = -ENOMEM;
-                       break;
-               }
+       kobjs = kcalloc(mrrm_mem_entry_num, sizeof(*kobjs), GFP_KERNEL);
+       if (!kobjs) {
+               kobject_put(pkobj);
+               return -ENOMEM;
+       }
 
+       for (i = 0; i < mrrm_mem_entry_num; i++) {
+               scnprintf(name, sizeof(name), "range%d", i);
                kobj = kobject_create_and_add(name, pkobj);
+               if (!kobj) {
+                       ret = -ENOMEM;
+                       goto cleanup;
+               }
 
                ret = sysfs_create_groups(kobj, memory_range_groups);
-               if (ret)
-                       return ret;
+               if (ret) {
+                       kobject_put(kobj);
+                       goto cleanup;
+               }
+               kobjs[i] = kobj;
        }
 
+       kfree(kobjs);
+       return 0;
+
+cleanup:
+       for (int j = 0; j < i; j++) {
+               if (kobjs[j]) {
+                       sysfs_remove_groups(kobjs[j], memory_range_groups);
+                       kobject_put(kobjs[j]);
+               }
+       }
+       kfree(kobjs);
+       kobject_put(pkobj);
        return ret;
 }