CVE-2022-49147

What it is

In the Linux kernel, the following vulnerability has been resolved: block: Fix the maximum minor value is blk_alloc_ext_minor() ida_alloc_range(..., min, max, ...) returns values from min to max, inclusive. So, NR_EXT_DEVT is a valid idx returned by blk_alloc_ext_minor(). This is an issue because in device_add_disk(), this value is used in: ddev->devt = MKDEV(disk->major, disk->first_minor); and NR_EXT_DEVT is '(1 << MINORBITS)'. So, should 'disk->first_minor' be NR_EXT_DEVT, it would overflow.

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2025-02-26 07:00 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 05:17 UTC Last updatedMost recent change to the record

Details

Published

2025-02-26 07:00 UTC

Last modified

2026-06-17 05:17 UTC

Exploit probability

0.3% · EPSS, next 30 days

Record status

Analyzed

Affected

• Linux Kernel < 5.15.33
• Linux Kernel < 5.16.19
• Linux Kernel < 5.17.2

Attack profile CVSS 3.1 · 5.5

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High