KVM: SVM: Fix memory leaks that happen when svm_create_vcpu() fails

svm_create_vcpu() does not free the pages allocated during the creation
when it fails to complete the allocations. This patch fixes it.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 445c594..2ba5820 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -706,29 +706,28 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
        if (err)
                goto free_svm;
 
+       err = -ENOMEM;
        page = alloc_page(GFP_KERNEL);
-       if (!page) {
-               err = -ENOMEM;
+       if (!page)
                goto uninit;
-       }
 
-       err = -ENOMEM;
        msrpm_pages = alloc_pages(GFP_KERNEL, MSRPM_ALLOC_ORDER);
        if (!msrpm_pages)
-               goto uninit;
+               goto free_page1;
 
        nested_msrpm_pages = alloc_pages(GFP_KERNEL, MSRPM_ALLOC_ORDER);
        if (!nested_msrpm_pages)
-               goto uninit;
-
-       svm->msrpm = page_address(msrpm_pages);
-       svm_vcpu_init_msrpm(svm->msrpm);
+               goto free_page2;
 
        hsave_page = alloc_page(GFP_KERNEL);
        if (!hsave_page)
-               goto uninit;
+               goto free_page3;
+
        svm->nested.hsave = page_address(hsave_page);
 
+       svm->msrpm = page_address(msrpm_pages);
+       svm_vcpu_init_msrpm(svm->msrpm);
+
        svm->nested.msrpm = page_address(nested_msrpm_pages);
 
        svm->vmcb = page_address(page);
@@ -744,6 +743,12 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
 
        return &svm->vcpu;
 
+free_page3:
+       __free_pages(nested_msrpm_pages, MSRPM_ALLOC_ORDER);
+free_page2:
+       __free_pages(msrpm_pages, MSRPM_ALLOC_ORDER);
+free_page1:
+       __free_page(page);
 uninit:
        kvm_vcpu_uninit(&svm->vcpu);
 free_svm: