Linux CVE-2026-23421

This vulnerability exists in the Linux kernel's DRM (Direct Rendering Manager) XE graphics driver configfs implementation. The configfs interface allows userspace configuration of graphics device parameters. During device initialization, wa_bb_store() allocates memory for both ctx_restore_post_bb and ctx_restore_mid_bb structures to store GPU command buffer sequences used for workarounds. However, the corresponding cleanup function xe_config_device_release() only deallocates ctx_restore_post_bb, leaving ctx_restore_mid_bb[0].cs unfreed. This is a classic resource management oversight where partial cleanup during device removal creates a memory leak. The leaked memory region may contain sensitive data from previous operations, creating an information disclosure vector. CWE classification indicates this falls under improper resource cleanup patterns common in kernel memory management.