CVE-2021-46937

In the Linux kernel, the following vulnerability has been resolved: mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()' DAMON debugfs interface increases the reference counts of 'struct pid's for targets from the 'target_ids' file write callback ('dbgfs_target_ids_write()'), but decreases the counts only in DAMON monitoring termination callback ('dbgfs_before_terminate()'). Therefore, when 'target_ids' file is repeatedly written without DAMON monitoring start/termination, the reference count is not decreased and therefore memory for the 'struct pid' cannot be freed. This commit fixes this issue by decreasing the reference counts when 'target_ids' is written.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/ebb3f994dd92f8fb4d70c7541091216c1e10cb71	Patch
https://git.kernel.org/stable/c/ffe4a1ba1a82c416a6b3a09d46594f6a885ae141	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

10 Apr 2024, 18:59

Type	Values Removed	Values Added
References	~~() https://git.kernel.org/stable/c/ebb3f994dd92f8fb4d70c7541091216c1e10cb71 -~~	() https://git.kernel.org/stable/c/ebb3f994dd92f8fb4d70c7541091216c1e10cb71 - Patch
References	~~() https://git.kernel.org/stable/c/ffe4a1ba1a82c416a6b3a09d46594f6a885ae141 -~~	() https://git.kernel.org/stable/c/ffe4a1ba1a82c416a6b3a09d46594f6a885ae141 - Patch
CWE		CWE-668
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5
First Time		Linux Linux linux Kernel
CPE		cpe:2.3:o:linux:linux_kernel::::::::

27 Feb 2024, 14:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2024-02-27 10:15

Updated : 2024-04-10 18:59

NVD link : CVE-2021-46937

Mitre link : CVE-2021-46937

CVE.ORG link : CVE-2021-46937

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-668

Exposure of Resource to Wrong Sphere

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