From 6ef4e07ecd2db21025c446327ecf34414366498b Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Sat, 24 Dec 2016 10:00:42 +0100 Subject: [PATCH] KVM: x86: reset MMU on KVM_SET_VCPU_EVENTS Otherwise, mismatch between the smm bit in hflags and the MMU role can cause a NULL pointer dereference. Cc: stable@vger.kernel.org Signed-off-by: Xiao Guangrong Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 445c51b6cf6d..0b387d61c103 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3070,6 +3070,8 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, memset(&events->reserved, 0, sizeof(events->reserved)); } +static void kvm_set_hflags(struct kvm_vcpu *vcpu, unsigned emul_flags); + static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events) { @@ -3106,10 +3108,13 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, vcpu->arch.apic->sipi_vector = events->sipi_vector; if (events->flags & KVM_VCPUEVENT_VALID_SMM) { + u32 hflags = vcpu->arch.hflags; if (events->smi.smm) - vcpu->arch.hflags |= HF_SMM_MASK; + hflags |= HF_SMM_MASK; else - vcpu->arch.hflags &= ~HF_SMM_MASK; + hflags &= ~HF_SMM_MASK; + kvm_set_hflags(vcpu, hflags); + vcpu->arch.smi_pending = events->smi.pending; if (events->smi.smm_inside_nmi) vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK; -- 2.39.5