KVM: x86: Gracefully handle __vmalloc() failure during VM allocation

commit d18b2f43b9147c8005ae0844fb445d8cc6a87e31 upstream.

Check the result of __vmalloc() to avoid dereferencing a NULL pointer in
the event that allocation failres.

Fixes: d1e5b0e98ea27 ("kvm: Make VM ioctl do valloc for some archs")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 0745912..51ff6b3 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1926,6 +1926,10 @@ static struct kvm *svm_vm_alloc(void)
        struct kvm_svm *kvm_svm = __vmalloc(sizeof(struct kvm_svm),
                                            GFP_KERNEL_ACCOUNT | __GFP_ZERO,
                                            PAGE_KERNEL);
+
+       if (!kvm_svm)
+               return NULL;
+
        return &kvm_svm->kvm;
 }
 

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 23f0879..e0d16ba 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6654,6 +6654,10 @@ static struct kvm *vmx_vm_alloc(void)
        struct kvm_vmx *kvm_vmx = __vmalloc(sizeof(struct kvm_vmx),
                                            GFP_KERNEL_ACCOUNT | __GFP_ZERO,
                                            PAGE_KERNEL);
+
+       if (!kvm_vmx)
+               return NULL;
+
        return &kvm_vmx->kvm;
 }