4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Xiao Guangrong <guangrong.x...@linux.intel.com> commit 6ef4e07ecd2db21025c446327ecf34414366498b upstream. Otherwise, mismatch between the smm bit in hflags and the MMU role can cause a NULL pointer dereference. Signed-off-by: Xiao Guangrong <guangrong.x...@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/x86/kvm/x86.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3036,6 +3036,8 @@ static void kvm_vcpu_ioctl_x86_get_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) { @@ -3072,10 +3074,13 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_e 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;