Executive brief
A vulnerability in the Linux kernel's virtualization component (KVM) for ARM64 systems could allow a local user to cause a system crash. The issue occurs when the system fails to properly set up a virtual interrupt controller, leading to an unstable state during cleanup. This primarily affects servers or devices running virtual machines, potentially resulting in a denial of service.
Technical details
A flaw exists in the KVM arm64 VGIC (Virtual Generic Interrupt Controller) initialization logic. If 'vgic_allocate_private_irqs_locked()' fails during 'kvm_vgic_create()', the function exits early without initializing 'dist->rd_regions'. Subsequent calls to 'kvm_vgic_dist_destroy()' attempt to traverse these uninitialized regions, leading to a kernel crash (walking into the weeds). The fix involves reordering initialization to ensure static structures are ready for teardown even if a partial failure occurs. This was identified via syzbot and has been patched in stable kernel branches.
Affected products
- Linux Linux Kernel arm64 architecture
Timeline
- 2026-02-28: other: Initial patch developed
- 2026-05-08: disclosed: CVE published