From 67ffa0e4618acd554a1c5a0fba54338e2bee0973 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 9 Dec 2014 14:33:45 +0100 Subject: [PATCH] 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: Jiri Slaby --- 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 d1c5946e33a2e..86dee11838ab3 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -218,6 +218,11 @@ 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; -- 2.47.3