{"id":"DEBIAN-CVE-2021-46972","details":"In the Linux kernel, the following vulnerability has been resolved:  ovl: fix leaked dentry  Since commit 6815f479ca90 (\"ovl: use only uppermetacopy state in ovl_lookup()\"), overlayfs doesn't put temporary dentry when there is a metacopy error, which leads to dentry leaks when shutting down the related superblock:    overlayfs: refusing to follow metacopy origin for (/file0)   ...   BUG: Dentry (____ptrval____){i=3f33,n=file3}  still in use (1) [unmount of overlay overlay]   ...   WARNING: CPU: 1 PID: 432 at umount_check.cold+0x107/0x14d   CPU: 1 PID: 432 Comm: unmount-overlay Not tainted 5.12.0-rc5 #1   ...   RIP: 0010:umount_check.cold+0x107/0x14d   ...   Call Trace:    d_walk+0x28c/0x950    ? dentry_lru_isolate+0x2b0/0x2b0    ? __kasan_slab_free+0x12/0x20    do_one_tree+0x33/0x60    shrink_dcache_for_umount+0x78/0x1d0    generic_shutdown_super+0x70/0x440    kill_anon_super+0x3e/0x70    deactivate_locked_super+0xc4/0x160    deactivate_super+0xfa/0x140    cleanup_mnt+0x22e/0x370    __cleanup_mnt+0x1a/0x30    task_work_run+0x139/0x210    do_exit+0xb0c/0x2820    ? __kasan_check_read+0x1d/0x30    ? find_held_lock+0x35/0x160    ? lock_release+0x1b6/0x660    ? mm_update_next_owner+0xa20/0xa20    ? reacquire_held_locks+0x3f0/0x3f0    ? __sanitizer_cov_trace_const_cmp4+0x22/0x30    do_group_exit+0x135/0x380    __do_sys_exit_group.isra.0+0x20/0x20    __x64_sys_exit_group+0x3c/0x50    do_syscall_64+0x45/0x70    entry_SYSCALL_64_after_hwframe+0x44/0xae   ...   VFS: Busy inodes after unmount of overlay. Self-destruct in 5 seconds.  Have a nice day...  This fix has been tested with a syzkaller reproducer.","modified":"2026-09-15T09:02:34.954393669Z","published":"2024-02-27T19:04:07.403Z","upstream":["CVE-2021-46972"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-46972"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.10.38-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-46972.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.10.38-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-46972.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.10.38-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-46972.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}