diff options
| author | Ido Yariv <ido@wizery.com> | 2016-10-21 12:39:57 -0400 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-04-11 10:57:41 +0200 |
| commit | 46c7036c4e91ce896a90a7a353c1eb0c61eab0e4 (patch) | |
| tree | cb90e129053abbdee4210185fa7610da27494e18 | |
| parent | fa33ed6cc7628e2791be3eb90a98db59b2445a81 (diff) | |
KVM: x86: fix wbinvd_dirty_mask use-after-free
commit bd768e146624cbec7122ed15dead8daa137d909d upstream.
vcpu->arch.wbinvd_dirty_mask may still be used after freeing it,
corrupting memory. For example, the following call trace may set a bit
in an already freed cpu mask:
kvm_arch_vcpu_load
vcpu_load
vmx_free_vcpu_nested
vmx_free_vcpu
kvm_arch_vcpu_free
Fix this by deferring freeing of wbinvd_dirty_mask.
Signed-off-by: Ido Yariv <ido@wizery.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim KrÄmáŠ<rkrcmar@redhat.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
| -rw-r--r-- | arch/x86/kvm/x86.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8e57771d4..fc68806e6 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6509,11 +6509,13 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) { + void *wbinvd_dirty_mask = vcpu->arch.wbinvd_dirty_mask; + kvmclock_reset(vcpu); - free_cpumask_var(vcpu->arch.wbinvd_dirty_mask); fx_free(vcpu); kvm_x86_ops->vcpu_free(vcpu); + free_cpumask_var(wbinvd_dirty_mask); } struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, |