CVE-2025-21661: gpio: virtuser: fix missing lookup table cleanups

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-01-21 · updated 2026-07-30
Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: gpio: virtuser: fix missing lookup table cleanups When a virtuser device is created via configfs and the probe fails due to an incorrect lookup table, the table is not removed. This prevents subsequent probe attempts from succeeding, even if the issue is corrected, unless the device is released. Additionally, cleanup is also needed in the less likely case of platform_device_register_full() failure. Besides, a consistent memory leak in lookup_table->dev_id was spotted using kmemleak by toggling the live state between 0 and 1 with a correct lookup table. Introduce gpio_virtuser_remove_lookup_table() as the counterpart to the existing gpio_virtuser_make_lookup_table() and call it from all necessary points to ensure proper cleanup.

Affected products

Linux kernel: from 6.11 before 6.12.10; 6.13-rc1, 6.13-rc2, 6.13-rc3, 6.13-rc4, 6.13-rc5, 6.13-rc6 — fixed in 6.12.10

How to fix

Upgrade to a fixed version: Linux kernel 6.12.10. Check the vendor advisory for mitigations.

References

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