CVE-2024-26773

ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()

Severity Score

5.5

*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:

ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()

Determine if the group block bitmap is corrupted before using ac_b_ex in
ext4_mb_try_best_found() to avoid allocating blocks from a group with a
corrupted block bitmap in the following concurrency and making the
situation worse.

ext4_mb_regular_allocator
ext4_lock_group(sb, group)
ext4_mb_good_group
// check if the group bbitmap is corrupted
ext4_mb_complex_scan_group
// Scan group gets ac_b_ex but doesn't use it
ext4_unlock_group(sb, group)
ext4_mark_group_bitmap_corrupted(group)
// The block bitmap was corrupted during
// the group unlock gap.
ext4_mb_try_best_found
ext4_lock_group(ac->ac_sb, group)
ext4_mb_use_best_found
mb_mark_used
// Allocating blocks in block bitmap corrupted group

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: ext4: evite asignar bloques de un grupo dañado en ext4_mb_try_best_found() Determine si el mapa de bits del bloque del grupo está dañado antes de usar ac_b_ex en ext4_mb_try_best_found() para evitar asignar bloques de un grupo con un bloque dañado mapa de bits en la siguiente concurrencia y empeorando la situación. ext4_mb_regular_allocator ext4_lock_group(sb, group) ext4_mb_good_group // verifica si el bbitmap del grupo está dañado ext4_mb_complex_scan_group // El grupo de escaneo obtiene ac_b_ex pero no lo usa ext4_unlock_group(sb, group) ext4_mark_group_bitmap_corrupted(group) // El mapa de bits del bloque se corrompió durante // el grupo desbloquea la brecha. ext4_mb_try_best_found ext4_lock_group(ac->ac_sb, group) ext4_mb_use_best_found mb_mark_used // Asignación de bloques en un grupo dañado de mapa de bits de bloques

A vulnerability was found in the ext4_mb_try_best_found() function in the Linux kernel. This issue could lead to memory corruption or crashes due to the allocation of blocks from a group with a corrupted block bitmap.

*Credits: N/A

CVSS Scores

Red Hatv3.1 5.5

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

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-02-19 CVE Reserved
2024-04-03 CVE Published
2024-04-04 EPSS Updated
2024-08-02 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-229: Improper Handling of Values

CAPEC

References (12)

URL	Tag	Source
https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html
https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/21f8cfe79f776287459343e9cfa6055af61328ea	2024-03-01
https://git.kernel.org/stable/c/260fc96283c0f594de18a1b045faf6d8fb42874d	2024-03-01
https://git.kernel.org/stable/c/927794a02169778c9c2e7b25c768ab3ea8c1dc03	2024-03-01
https://git.kernel.org/stable/c/4c21fa60a6f4606f6214a38f50612b17b2f738f5	2024-03-01
https://git.kernel.org/stable/c/f97e75fa4e12b0aa0224e83fcbda8853ac2adf36	2024-03-01
https://git.kernel.org/stable/c/0184747b552d6b5a14db3b7fcc3b792ce64dedd1	2024-03-01
https://git.kernel.org/stable/c/a2576ae9a35c078e488f2c573e9e6821d651fbbe	2024-03-01
https://git.kernel.org/stable/c/4530b3660d396a646aad91a787b6ab37cf604b53	2024-01-18

URL	Date	SRC
https://access.redhat.com/security/cve/CVE-2024-26773	2024-09-18
https://bugzilla.redhat.com/show_bug.cgi?id=2273236	2024-09-18

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"				< 4.19.308 Search vendor "Linux" for product "Linux Kernel" and version " < 4.19.308"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.4.270 Search vendor "Linux" for product "Linux Kernel" and version " < 5.4.270"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.10.211 Search vendor "Linux" for product "Linux Kernel" and version " < 5.10.211"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 5.15.150 Search vendor "Linux" for product "Linux Kernel" and version " < 5.15.150"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 6.1.80 Search vendor "Linux" for product "Linux Kernel" and version " < 6.1.80"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 6.6.19 Search vendor "Linux" for product "Linux Kernel" and version " < 6.6.19"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 6.7.7 Search vendor "Linux" for product "Linux Kernel" and version " < 6.7.7"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				< 6.8 Search vendor "Linux" for product "Linux Kernel" and version " < 6.8"		en		Affected