KVM: VMX: fix use after free of vmx->loaded_vmcs

After free_loaded_vmcs executes, the "loaded_vmcs" structure is kfreed, and now vmx->loaded_vmcs points to a kfreed area. Subsequent free_loaded_vmcs then attempts to manipulate vmx->loaded_vmcs. Switch the order to avoid the problem. https://bugzilla.redhat.com/show_bug.cgi?id=1047892 Reviewed-by: Jan Kiszka <[email protected]> Signed-off-by: Marcelo Tosatti <[email protected]>
dtwlin · Jan 8, 2014 · 26a865f · 26a865f
1 parent 9689397
commit 26a865f
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
@@ -7390,8 +7390,8 @@ static void vmx_free_vcpu(struct kvm_vcpu *vcpu)
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 
 	free_vpid(vmx);
-	free_nested(vmx);
 	free_loaded_vmcs(vmx->loaded_vmcs);
+	free_nested(vmx);
 	kfree(vmx->guest_msrs);
 	kvm_vcpu_uninit(vcpu);
 	kmem_cache_free(kvm_vcpu_cache, vmx);