CVE-2025-21695
Published: February 13, 2025Last modified: February 13, 2025
Description
In the Linux kernel, the following vulnerability has been resolved: platform/x86: dell-uart-backlight: fix serdev race The dell_uart_bl_serdev_probe() function calls devm_serdev_device_open() before setting the client ops via serdev_device_set_client_ops(). This ordering can trigger a NULL pointer dereference in the serdev controller's receive_buf handler, as it assumes serdev->ops is valid when SERPORT_ACTIVE is set. This is similar to the issue fixed in commit 5e700b384ec1 ("platform/chrome: cros_ec_uart: properly fix race condition") where devm_serdev_device_open() was called before fully initializing the device. Fix the race by ensuring client ops are set before enabling the port via devm_serdev_device_open(). Note, serdev_device_set_baudrate() and serdev_device_set_flow_control() calls should be after the devm_serdev_device_open() call.
Severity score breakdown
| Parameter | Value | 
|---|---|
| Base score | 4.7 | 
| Attack Vector | LOCAL | 
| Attack complexity | HIGH | 
| Privileges required | LOW | 
| User interaction | NONE | 
| Scope | UNCHANGED | 
| Confidentiality | NONE | 
| Integrity impact | NONE | 
| Availability impact | HIGH | 
| Vector | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H | 
Status
| Product | Release | Package | Status | 
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Not affected (6.1.33-r0) | 
| 25 LTS | linux-lts | Fixed (6.12.41-r0) | |
| Stream | linux-lts | Fixed (6.12.41-r0) |