Re: [PATCH v3] KVM: remove buggy vcpu id check on vcpu creation

From: Greg Kurz
Date: Wed Apr 20 2016 - 13:53:43 EST


On Wed, 20 Apr 2016 19:27:06 +0200
Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx> wrote:

> 2016-04-20 18:09+0100, James Hogan:
> > On Wed, Apr 20, 2016 at 07:02:10PM +0200, Radim KrÄmÃÅ wrote:
> >> 2016-04-20 17:44+0200, Greg Kurz:
> >> > diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
> >> > index 70ef1a43c114..0278ea146db5 100644
> >> > --- a/arch/mips/kvm/mips.c
> >> > +++ b/arch/mips/kvm/mips.c
> >> > @@ -248,9 +248,14 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
> >> > int err, size, offset;
> >> > void *gebase;
> >> > int i;
> >> > + struct kvm_vcpu *vcpu;
> >> >
> >> > - struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
> >> > + if (id >= KVM_MAX_VCPUS) {
> >> > + err = -EINVAL;
> >> > + goto out;
> >>
> >> 'vcpu' looks undefined at this point, so kfree in 'out:' may bug.
> >
> > Thats out_free_cpu I think?
>
> My bad, it is. Thank you!
>

I kept the goto based construct because it was done this way for kzalloc().
but I agree that 'return ERR_PTR(-EINVAL)' may look more explicit.

Worth a v4 ?

Cheers.

--
Greg