From 25995e5b4aa308e5264cf7cf3e86871acf6a8b8c Mon Sep 17 00:00:00 2001 From: =?utf8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Thu, 27 Nov 2014 23:30:19 +0100 Subject: [PATCH] KVM: x86: check bounds of APIC maps MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit They can't be violated now, but play it safe for the future. Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index bd82054664fd..e1940fccaf6c 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -193,15 +193,16 @@ static void recalculate_apic_map(struct kvm *kvm) kvm_for_each_vcpu(i, vcpu, kvm) { struct kvm_lapic *apic = vcpu->arch.apic; u16 cid, lid; - u32 ldr; - - new->phys_map[kvm_apic_id(apic)] = apic; + u32 ldr, aid; + aid = kvm_apic_id(apic); ldr = kvm_apic_get_reg(apic, APIC_LDR); cid = apic_cluster_id(new, ldr); lid = apic_logical_id(new, ldr); - if (lid) + if (aid < ARRAY_SIZE(new->phys_map)) + new->phys_map[aid] = apic; + if (lid && cid < ARRAY_SIZE(new->logical_map)) new->logical_map[cid][ffs(lid) - 1] = apic; } out: -- 2.20.1