// For flags

CVE-2024-26601

ext4: regenerate buddy after block freeing failed if under fc replay

Severity Score

5.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved:

ext4: regenerate buddy after block freeing failed if under fc replay

This mostly reverts commit 6bd97bf273bd ("ext4: remove redundant
mb_regenerate_buddy()") and reintroduces mb_regenerate_buddy(). Based on
code in mb_free_blocks(), fast commit replay can end up marking as free
blocks that are already marked as such. This causes corruption of the
buddy bitmap so we need to regenerate it in that case.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: regenerar amigo después de que falló la liberación del bloque si se encuentra en reproducción fc. Esto revierte principalmente el commit 6bd97bf273bd ("ext4: eliminar mb_regenerate_buddy() redundante") y reintroduce mb_regenerate_buddy(). Según el código en mb_free_blocks(), la repetición de commit rápido puede terminar marcando como bloques libres que ya están marcados como tales. Esto causa corrupción en el mapa de bits del amigo, por lo que debemos regenerarlo en ese caso.

A flaw was found in the Linux kernel's ext4 filesystem related to the fast commit replay process. During this process, blocks that are already marked as free can be incorrectly marked as free again, leading to the corruption of the buddy bitmap, which is used to track free and allocated blocks. This corruption can result in filesystem inconsistencies and potential data loss. The issue is resolved by reintroducing the mb_regenerate_buddy() function, which regenerates the buddy bitmap to ensure its integrity.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-19 CVE Reserved
  • 2024-02-24 CVE Published
  • 2024-04-21 EPSS Updated
  • 2024-08-02 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-118: Incorrect Access of Indexable Resource ('Range Error')
CAPEC
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"
 >= 5.10.181 < 5.10.211
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10.181 < 5.10.211"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 5.15.150
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 5.15.150"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 6.1.78
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 6.1.78"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 6.6.17
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 6.6.17"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 6.7.5
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 6.7.5"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.11 < 6.8
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.11 < 6.8"
en
Affected