vulnerability
Ubuntu: (Multiple Advisories) (CVE-2025-21685): Linux kernel vulnerabilities
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:L/AC:M/Au:S/C:N/I:N/A:C) | Feb 9, 2025 | Apr 24, 2025 | Aug 18, 2025 |
Description
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: lenovo-yoga-tab2-pro-1380-fastcharger: fix serdev race
The yt2_1380_fc_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.
Solutions
References
- CVE-2025-21685
- https://attackerkb.com/topics/CVE-2025-21685
- CWE-476
- UBUNTU-USN-7445-1
- UBUNTU-USN-7448-1
- URL-https://git.kernel.org/linus/59616a91e5e74833b2008b56c66879857c616006
- URL-https://git.kernel.org/stable/c/3f67e07873df3c6d9ce2582260b83732e1d3a40b
- URL-https://git.kernel.org/stable/c/59616a91e5e74833b2008b56c66879857c616006
- URL-https://ubuntu.com/security/notices/USN-7445-1
- URL-https://ubuntu.com/security/notices/USN-7448-1
- URL-https://www.cve.org/CVERecord?id=CVE-2025-21685
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