UBUNTU-CVE-2021-46972

Advisory lineage Upstream: 1 Downstream: 0
Upstream
CVE-2021-46972
Published: 27 Feb 2024, 19:04
Last modified:24 Oct 2025, 04:50

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

27 Feb 2024, 19:04
Published
Vulnerability first disclosed
24 Oct 2025, 04:50
Last Modified
Vulnerability information updated

Description

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.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Systems

  • ubuntu•linux-allwinner-5.19

    all

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.11

    all

  • ubuntu•linux-aws-5.13

    all

  • ubuntu•linux-aws-5.19

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.8

    all

  • ubuntu•linux-aws-6.2

    all

  • ubuntu•linux-azure

    all

  • ubuntu•linux-azure-5.11

    all

  • ubuntu•linux-azure-5.13

    all

  • ubuntu•linux-azure-5.19

    all

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.8

    all

  • ubuntu•linux-azure-6.2

    all

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fde

    all

  • ubuntu•linux-azure-fde-5.19

    all

  • ubuntu•linux-azure-fde-6.2

    all

  • ubuntu•linux-gcp

    all

  • ubuntu•linux-gcp-5.11

    all

  • ubuntu•linux-gcp-5.13

    all

  • ubuntu•linux-gcp-5.19

    all

  • ubuntu•linux-gcp-5.3

    all

  • ubuntu•linux-gcp-5.8

    all

  • ubuntu•linux-gcp-6.2

    all

  • ubuntu•linux-gke

    all

  • ubuntu•linux-gke-4.15

    all

  • ubuntu•linux-gke-5.15

    all

  • ubuntu•linux-gke-5.4

    all

  • ubuntu•linux-gkeop-5.4

    all

  • ubuntu•linux-hwe

    all

  • ubuntu•linux-hwe-5.11

    all

  • ubuntu•linux-hwe-5.13

    all

  • ubuntu•linux-hwe-5.19

    all

  • ubuntu•linux-hwe-5.8

    all

  • ubuntu•linux-hwe-6.2

    all

  • ubuntu•linux-hwe-edge

    all | all

  • ubuntu•linux-intel-5.13

    all

  • ubuntu•linux-lowlatency-hwe-5.19

    all

  • ubuntu•linux-lowlatency-hwe-6.2

    all

  • ubuntu•linux-nvidia-6.2

    all

  • ubuntu•linux-oem

    all

  • ubuntu•linux-oem-5.10

    all

  • ubuntu•linux-oem-5.13

    all

  • ubuntu•linux-oem-5.14

    all

  • ubuntu•linux-oem-5.17

    all

  • ubuntu•linux-oem-5.6

    all

  • ubuntu•linux-oem-6.0

    all

  • ubuntu•linux-oem-6.1

    all

Showing first 50 affected entries in server-rendered view.

References (6)