CVE-2026-63804

The CVE-2026-63804 issue is a gfs2 use-after-free in gfs2_qd_dealloc triggered by an RCU callback accessing sdp after qd is freed. The root cause is that gfs2_put_super() may free the superblock via free_sbd() before pending RCU callbacks (including gfs2_qd_dealloc) complete. The public details i...