CVE-2025-38036
BaseFortify
Publication date: 2025-06-18
Last updated on: 2025-11-14
Assigner: kernel.org
Description
Description
CVSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | From 5.15.160 (inc) to 5.16 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-NVD-CWE-noinfo |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in the Linux kernel involves the drm/xe/vf component where Virtual Functions (VFs) need to communicate with the GuC to obtain the GMDID value. Due to recent code refactoring, the GT's MMIO (Memory-Mapped I/O) members are initialized later than before. As a result, when the VF tries to use GuC functions that rely on MMIO reads or writes, it leads to a null pointer dereference (NPD) crash because the MMIO register address is not set. The fix involves performing early initialization of the GT MMIO to ensure GuC functions work correctly and prevent the crash.
How can this vulnerability impact me? :
This vulnerability can cause the system to crash due to a null pointer dereference when the Virtual Function attempts to communicate with the GuC using MMIO functions before the MMIO registers are properly initialized. This can lead to instability or denial of service in environments using SR-IOV VF mode with the affected Linux kernel component.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by monitoring system logs for specific error messages related to the drm/xe driver in SR-IOV VF mode. Look for kernel log entries indicating issues such as 'Running in SR-IOV VF mode', 'GT0: sending H2G MMIO', and 'BUG: unable to handle page fault for address'. Commands like 'dmesg | grep drm' or 'journalctl -k | grep drm' can help identify these messages.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation involves ensuring that the Linux kernel is updated to a version where the early GT MMIO initialization (xe_gt_mmio_init()) is performed before GuC communication in the drm/xe driver. This prevents the VF from causing a page fault due to unset MMIO register addresses. Until an update is applied, avoid using SR-IOV VF mode with the affected driver to prevent crashes.