CVE-2021-47579

ovl: fix warning in ovl_create_real()

Severity Score

4.1

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

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.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ovl: corregir advertencia en ovl_create_real() Syzbot activó la siguiente advertencia en ovl_workdir_create() -> ovl_create_real(): if (!err && WARN_ON(!newdentry->d_inode)) { La razón es que el sistema de archivos cgroup2 regresa desde mkdir sin crear una instancia del nuevo dentry. Los sistemas de archivos extraños como este serán rechazados por overlayfs en una etapa posterior durante la instalación, pero para evitar dicha advertencia, llame a ovl_mkdir_real() directamente desde ovl_workdir_create() y rechace este caso anticipadamente.

*Credits: N/A

CVSS Scores

Red Hatv3.1 4.1

Attack Vector

Local

Attack Complexity

High

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-05-24 CVE Reserved
2024-06-19 CVE Published
2024-06-20 EPSS Updated
2024-09-11 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-457: Use of Uninitialized Variable

CAPEC

References (7)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/445d2dc63e5871d218f21b8f62ab29ac72f2e6b8	2021-12-22
https://git.kernel.org/stable/c/f9f300a92297be8250547347fd52216ef0177ae0	2021-12-22
https://git.kernel.org/stable/c/6859985a2fbda5d1586bf44538853e1be69e85f7	2021-12-22
https://git.kernel.org/stable/c/d2ccdd4e4efab06178608a34d7bfb20a54104c02	2021-12-22
https://git.kernel.org/stable/c/1f5573cfe7a7056e80a92c7a037a3e69f3a13d1c	2021-11-04

URL	Date	SRC
https://access.redhat.com/security/cve/CVE-2021-47579	2024-08-08
https://bugzilla.redhat.com/show_bug.cgi?id=2293250	2024-08-08

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 4.19.222 Search vendor "Linux" for product "Linux Kernel" and version " < 4.19.222"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.4.168 Search vendor "Linux" for product "Linux Kernel" and version " < 5.4.168"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.10.88 Search vendor "Linux" for product "Linux Kernel" and version " < 5.10.88"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.15.11 Search vendor "Linux" for product "Linux Kernel" and version " < 5.15.11"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.16 Search vendor "Linux" for product "Linux Kernel" and version " < 5.16"		en		Affected