CVE-2025-38392: 
Linux Kernel vulnerability analysis and mitigation

CVE-2025-38392 is a vulnerability in the Linux kernel's Intel idpf driver, discovered and disclosed on July 24, 2025. The issue involves an invalid use of mutexlock() in atomic context when VIRTCHNL2CAP_MACFILTER is enabled. This vulnerability affects systems running Red Hat Enterprise Linux versions 8.10 (and later), 9, and 10 with the Intel idpf driver (Red Hat CVE).

The vulnerability occurs when the driver attempts to acquire a mutex while holding spinlocks or in atomic context through _devopen(). The issue manifests in the control queue mutex handling, generating kernel warnings when VIRTCHNL2CAPMACFILTER is enabled. The vulnerability has been assigned a CVSS v3.1 score of 7.3 (AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H) and is categorized under CWE-767 (Red Hat CVE).

The vulnerability primarily affects system availability, with a high risk of causing kernel hangs or soft lockups when triggered by an unprivileged user. While the impact on confidentiality and integrity is low, the vulnerability presents a significant risk to system availability, particularly on systems using the Intel idpf driver with MAC filtering enabled. The issue extends beyond log flooding and can potentially result in local denial-of-service conditions (Red Hat CVE).

The primary mitigation is to prevent the idpf module from being loaded. Red Hat provides guidance on blacklisting kernel modules to prevent automatic loading, which can be implemented as a temporary workaround. For a permanent fix, the solution involves converting the cqlock to a spinlock and ensuring that memory used in atomic contexts is allocated with DMAATTRFORCECONTIGUOUS to avoid vunmap() calls under spinlock (Red Hat CVE).