From c9fdda04b9041f8105e4308078a2519bc6928852 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 17 Jun 2015 14:43:35 +0100 Subject: KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers [ Upstream commit 4839ddc27b7212ec58874f62c97da7400c8523be ] Commit fd1d0ddf2ae9 (KVM: arm/arm64: check IRQ number on userland injection) rightly limited the range of interrupts userspace can inject in a guest, but failed to consider the (unlikely) case where a guest is configured with 1024 interrupts. In this case, interrupts ranging from 1020 to 1023 are unuseable, as they have a special meaning for the GIC CPU interface. Make sure that these number cannot be used as an IRQ. Also delete a redundant (and similarily buggy) check in kvm_set_irq. Reported-by: Peter Maydell Cc: Andre Przywara Cc: # 4.1, 4.0, 3.19, 3.18 Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin --- virt/kvm/arm/vgic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 5f67fadfca65..d7cf2ffc56e9 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1721,7 +1721,7 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, goto out; } - if (irq_num >= kvm->arch.vgic.nr_irqs) + if (irq_num >= min(kvm->arch.vgic.nr_irqs, 1020)) return -EINVAL; vcpu_id = vgic_update_irq_pending(kvm, cpuid, irq_num, level); -- cgit v1.2.3