CVE-2025-38620

In the Linux kernel, the following vulnerability has been resolved: zloop: fix KASAN use-after-free of tag set When a zoned loop device, or zloop device, is removed, KASAN enabled kernel reports "BUG KASAN use-after-free" in blk_mq_free_tag_set(). The BUG happens because zloop_ctl_remove() calls put_disk(), which invokes zloop_free_disk(). The zloop_free_disk() frees the memory allocated for the zlo pointer. However, after the memory is freed, zloop_ctl_remove() calls blk_mq_free_tag_set(&zlo->tag_set), which accesses the freed zlo. Hence the KASAN use-after-free. zloop_ctl_remove() put_disk(zlo->disk) put_device() kobject_put() ... zloop_free_disk() kvfree(zlo) blk_mq_free_tag_set(&zlo->tag_set) To avoid the BUG, move the call to blk_mq_free_tag_set(&zlo->tag_set) from zloop_ctl_remove() into zloop_free_disk(). This ensures that the tag_set is freed before the call to kvfree(zlo).

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/765761851d89c772f482494d452e266795460278	Patch
https://git.kernel.org/stable/c/c7c87046b41a9ef28ee7ac476c369da5b5228bc5	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:6.16:*:*:*:*:*:*:*

History

26 Nov 2025, 17:45

Type	Values Removed	Values Added
First Time		Linux linux Kernel Linux
CWE		CWE-416
References	~~() https://git.kernel.org/stable/c/765761851d89c772f482494d452e266795460278 -~~	() https://git.kernel.org/stable/c/765761851d89c772f482494d452e266795460278 - Patch
References	~~() https://git.kernel.org/stable/c/c7c87046b41a9ef28ee7ac476c369da5b5228bc5 -~~	() https://git.kernel.org/stable/c/c7c87046b41a9ef28ee7ac476c369da5b5228bc5 - Patch
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.8
CPE		cpe:2.3:o:linux:linux_kernel:6.16:::::::*

Information

Published : 2025-08-22 16:15

Updated : 2025-11-26 17:45

NVD link : CVE-2025-38620

Mitre link : CVE-2025-38620

CVE.ORG link : CVE-2025-38620

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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