sysfs kobject lifecycle

The sysfs kobject lifecycle tag covers discussions around the creation, initialization, and cleanup of kernel objects (kobjects) within the sysfs filesystem, particularly in the context of Linux kernel memory management and security. A recurring theme is the handling of error paths during kobject initialization, such as when kobject_init_and_add() fails, which can lead to double-free vulnerabilities. The tag content focuses on a specific CVE (CVE-2026-46164) affecting Btrfs, where a double-free of a space-info sub-group object occurs due to improper lifecycle management. This highlights broader concerns about memory safety in kernel code, especially in rarely executed error paths that can still pose security risks.