From 4811cb9e8d36b8395e884322e49deb8963e8f094 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 9 Dec 2014 14:33:45 +0100 Subject: arm/arm64: KVM: Don't allow creating VCPUs after vgic_initialized commit 716139df2517fbc3f2306dbe8eba0fa88dca0189 upstream. When the vgic initializes its internal state it does so based on the number of VCPUs available at the time. If we allow KVM to create more VCPUs after the VGIC has been initialized, we are likely to error out in unfortunate ways later, perform buffer overflows etc. Acked-by: Marc Zyngier Reviewed-by: Eric Auger Signed-off-by: Christoffer Dall Signed-off-by: Shannon Zhao Signed-off-by: Greg Kroah-Hartman --- arch/arm/kvm/arm.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 039df03069d3..2e74a617147d 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -220,6 +220,11 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) int err; struct kvm_vcpu *vcpu; + if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) { + err = -EBUSY; + goto out; + } + vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL); if (!vcpu) { err = -ENOMEM; -- cgit v1.2.3