diff options
| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2019-04-25 19:01:09 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-04-30 21:22:15 +0200 |
| commit | b904cb8dff824b79233e82c078837627ebd52717 (patch) | |
| tree | 52455de1292a96b7b5d65f0b99556cfe69422d3d | |
| parent | 76d58e0f07ec203bbdfcaabd9a9fc10a5a3ed5ea (diff) | |
KVM: lapic: Check for in-kernel LAPIC before deferencing apic pointer
...to avoid dereferencing a null pointer when querying the per-vCPU
timer advance.
Fixes: 39497d7660d98 ("KVM: lapic: Track lapic timer advance per vCPU")
Reported-by: syzbot+f7e65445a40d3e0e4ebf@syzkaller.appspotmail.com
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/lapic.c | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 3 |
2 files changed, 2 insertions, 4 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index e0fa6fc0b2d8..bd13fdddbdc4 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1507,9 +1507,6 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu) u32 timer_advance_ns = apic->lapic_timer.timer_advance_ns; u64 guest_tsc, tsc_deadline, ns; - if (!lapic_in_kernel(vcpu)) - return; - if (apic->lapic_timer.expired_tscdeadline == 0) return; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 57621313dead..b5edc8e3ce1d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7894,7 +7894,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) } trace_kvm_entry(vcpu->vcpu_id); - if (vcpu->arch.apic->lapic_timer.timer_advance_ns) + if (lapic_in_kernel(vcpu) && + vcpu->arch.apic->lapic_timer.timer_advance_ns) wait_lapic_expire(vcpu); guest_enter_irqoff(); |