CVE-2024-39495: greybus: Fix use-after-free bug in gb_interface_release due to race condition.

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-07-12 · updated 2026-06-17
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: greybus: Fix use-after-free bug in gb_interface_release due to race condition. In gb_interface_create, &intf->mode_switch_completion is bound with gb_interface_mode_switch_work. Then it will be started by gb_interface_request_mode_switch. Here is the relevant code. if (!queue_work(system_long_wq, &intf->mode_switch_work)) { ... } If we call gb_interface_release to make cleanup, there may be an unfinished work. This function will call kfree to free the object "intf". However, if gb_interface_mode_switch_work is scheduled to run after kfree, it may cause use-after-free error as gb_interface_mode_switch_work will use the object "intf". The possible execution flow that may lead to the issue is as follows: CPU0 CPU1 | gb_interface_create | gb_interface_request_mode_switch gb_interface_release | kfree(intf) (free) | | gb_interface_mode_switch_work | mutex_lock(&intf->mutex) (use) Fix it by canceling the work before kfree.

Affected products

Linux kernel: before 5.4.279; from 5.5 before 5.10.221; from 5.11 before 5.15.162; from 5.16 before 6.1.95; from 6.2 before 6.6.35; from 6.7 before 6.9.6 — fixed in 5.10.221, 5.15.162, 5.4.279, 6.1.95, 6.6.35, 6.9.6

How to fix

Upgrade to a fixed version: Linux kernel 5.10.221, 5.15.162, 5.4.279, 6.1.95. Check the vendor advisory for mitigations.

References

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