CVE-2024-44948

In the Linux kernel, the following vulnerability has been resolved: x86/mtrr: Check if fixed MTRRs exist before saving them MTRRs have an obsolete fixed variant for fine grained caching control of the 640K-1MB region that uses separate MSRs. This fixed variant has a separate capability bit in the MTRR capability MSR. So far all x86 CPUs which support MTRR have this separate bit set, so it went unnoticed that mtrr_save_state() does not check the capability bit before accessing the fixed MTRR MSRs. Though on a CPU that does not support the fixed MTRR capability this results in a #GP. The #GP itself is harmless because the RDMSR fault is handled gracefully, but results in a WARN_ON(). Add the missing capability check to prevent this.

It was discovered that the CIFS network file system implementation in the Linux kernel did not properly validate certain SMB messages, leading to an out-of-bounds read vulnerability. An attacker could use this to cause a denial of service or possibly expose sensitive information. Supraja Sridhara, Benedict Schlüter, Mark Kuhne, Andrin Bertschi, and Shweta Shinde discovered that the Confidential Computing framework in the Linux kernel for x86 platforms did not properly handle 32-bit emulation on TDX and SEV. An attacker with access to the VMM could use this to cause a denial of service or possibly execute arbitrary code.