From 2204ae3c96e9a1fed50f7ee19ce092e69d7dfe82 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Thu, 29 Oct 2009 13:44:16 -0200 Subject: [PATCH] KVM: x86: disallow KVM_{SET,GET}_LAPIC without allocated in-kernel lapic Otherwise kvm might attempt to dereference a NULL pointer. Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- arch/x86/kvm/x86.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 97f6f9565ac..cd6fe0a5797 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1893,6 +1893,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp, switch (ioctl) { case KVM_GET_LAPIC: { + r = -EINVAL; + if (!vcpu->arch.apic) + goto out; lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL); r = -ENOMEM; @@ -1908,6 +1911,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp, break; } case KVM_SET_LAPIC: { + r = -EINVAL; + if (!vcpu->arch.apic) + goto out; lapic = kmalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL); r = -ENOMEM; if (!lapic)