summaryrefslogtreecommitdiff
path: root/arch/x86
diff options
context:
space:
mode:
authorIdo Yariv <ido@wizery.com>2016-10-21 12:39:57 -0400
committerPaolo Bonzini <pbonzini@redhat.com>2016-10-28 11:35:21 +0200
commitbd768e146624cbec7122ed15dead8daa137d909d (patch)
tree97cb14f789f62df6e85c5efad79f4d488df209ed /arch/x86
parent796f4687bd622b0f8076b6695001ab5cdc2b722a (diff)
KVM: x86: fix wbinvd_dirty_mask use-after-free
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. Cc: stable@vger.kernel.org Signed-off-by: Ido Yariv <ido@wizery.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/kvm/x86.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0b2087981c06..e954be8a3185 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7410,10 +7410,12 @@ 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);
kvm_x86_ops->vcpu_free(vcpu);
+ free_cpumask_var(wbinvd_dirty_mask);
}
struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,