CVE-2024-50192: 
Linux Kernel vulnerability analysis and mitigation

CVE-2024-50192 affects the Linux kernel's irqchip/gic-v4 component. The vulnerability was discovered by Kunkun Jiang and involves a race condition where userspace can force a change of affinity for a Virtual Processing Element (VPE) while it has already been unmapped, but the corresponding doorbell interrupt remains visible in /proc/irq/. The issue affects Linux kernel versions from 5.6 through 6.11.5 (NVD).

The vulnerability exists in the GICv4 interrupt controller implementation where there is a small window of opportunity for a race condition. The issue occurs when a VPE is being unmapped but its doorbell interrupt is still accessible through /proc/irq/. The fix involves checking the value of vmapp_count, which tracks whether the VPE is mapped or not, and returning an error if attempting to change affinity on an unmapped VPE. The CVSS v3.1 base score is 4.7 (Medium) with vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H (NVD).

The vulnerability could potentially lead to system instability or denial of service conditions when exploited, as indicated by the CVSS metrics showing high impact on availability but no impact on confidentiality or integrity (NVD).

The vulnerability requires local access and has high attack complexity, as indicated by the CVSS metrics (AV:L/AC:H). Low privileges are required to exploit the vulnerability, but no user interaction is needed (NVD).

The vulnerability has been patched in the Linux kernel. The fix involves adding a check for the vmapp_count value before allowing VMOVP operations and making vmapp_count common to both GICv4.1 and its v4.0 ancestor. Multiple Linux distributions have released updates to address this vulnerability, including Red Hat Enterprise Linux and Ubuntu (Red Hat Advisory).