CVE-2021-47579
ovl: fix warning in ovl_create_real()
Description
In the Linux kernel, the following vulnerability has been resolved: ovl: fix warning in ovl_create_real() Syzbot triggered the following warning in ovl_workdir_create() -> ovl_create_real(): if (!err && WARN_ON(!newdentry->d_inode)) { The reason is that the cgroup2 filesystem returns from mkdir without instantiating the new dentry. Weird filesystems such as this will be rejected by overlayfs at a later stage during setup, but to prevent such a warning, call ovl_mkdir_real() directly from ovl_workdir_create() and reject this case early.
INFO
Published Date :
June 19, 2024, 3:15 p.m.
Last Modified :
Sept. 29, 2025, 5:15 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the affected kernel packages.
- Update the affected packages.
- Reboot the system to apply the updates.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-47579.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-47579 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-47579
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-47579 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-47579 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Sep. 29, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE NVD-CWE-noinfo Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.11 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.88 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.20 up to (excluding) 5.4.168 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions up to (excluding) 4.19.222 Added Reference Type CVE: https://git.kernel.org/stable/c/1f5573cfe7a7056e80a92c7a037a3e69f3a13d1c Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/1f5573cfe7a7056e80a92c7a037a3e69f3a13d1c Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/445d2dc63e5871d218f21b8f62ab29ac72f2e6b8 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/445d2dc63e5871d218f21b8f62ab29ac72f2e6b8 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/6859985a2fbda5d1586bf44538853e1be69e85f7 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/6859985a2fbda5d1586bf44538853e1be69e85f7 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/d2ccdd4e4efab06178608a34d7bfb20a54104c02 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/d2ccdd4e4efab06178608a34d7bfb20a54104c02 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/f9f300a92297be8250547347fd52216ef0177ae0 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/f9f300a92297be8250547347fd52216ef0177ae0 Types: Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/1f5573cfe7a7056e80a92c7a037a3e69f3a13d1c Added Reference https://git.kernel.org/stable/c/445d2dc63e5871d218f21b8f62ab29ac72f2e6b8 Added Reference https://git.kernel.org/stable/c/6859985a2fbda5d1586bf44538853e1be69e85f7 Added Reference https://git.kernel.org/stable/c/d2ccdd4e4efab06178608a34d7bfb20a54104c02 Added Reference https://git.kernel.org/stable/c/f9f300a92297be8250547347fd52216ef0177ae0 -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 19, 2024
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: ovl: fix warning in ovl_create_real() Syzbot triggered the following warning in ovl_workdir_create() -> ovl_create_real(): if (!err && WARN_ON(!newdentry->d_inode)) { The reason is that the cgroup2 filesystem returns from mkdir without instantiating the new dentry. Weird filesystems such as this will be rejected by overlayfs at a later stage during setup, but to prevent such a warning, call ovl_mkdir_real() directly from ovl_workdir_create() and reject this case early. Added Reference kernel.org https://git.kernel.org/stable/c/445d2dc63e5871d218f21b8f62ab29ac72f2e6b8 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/f9f300a92297be8250547347fd52216ef0177ae0 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/6859985a2fbda5d1586bf44538853e1be69e85f7 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/d2ccdd4e4efab06178608a34d7bfb20a54104c02 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/1f5573cfe7a7056e80a92c7a037a3e69f3a13d1c [No types assigned]