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References: <20220308092047.1008409-1-butterflyhuangxx@gmail.com> <YicoOC+WZhNLq+pX@kroah.com>
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From:   butt3rflyh4ck <butterflyhuangxx@gmail.com>
Date:   Tue, 15 Mar 2022 16:04:01 +0800
Message-ID: <CAFcO6XO9JMMyWmiuR9mP0S7vxjeBHA+KT6vwCg3pqnqy-vnMxA@mail.gmail.com>
Subject: Re: [PATCH] virt: acrn: fix a memory leak in acrn_dev_ioctl()
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Li Fei1 <fei1.li@intel.com>, LKML <linux-kernel@vger.kernel.org>
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On Tue, Mar 8, 2022 at 5:56 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Tue, Mar 08, 2022 at 05:20:47PM +0800, Xiaolong Huang wrote:
> > The vm_param and cpu_regs need to be freed via kfree()
> > before return -EINVAL error.
> >
> > Fixes: 9c5137aedd11 ("virt: acrn: Introduce VM management interfaces")
> > Fixes: 2ad2aaee1bc9 ("virt: acrn: Introduce an ioctl to set vCPU registers state")
> > Signed-off-by: Xiaolong Huang <butterflyhuangxx@gmail.com>
> > Signed-off-by: Fei Li <fei1.li@intel.com>
> > ---
> >  drivers/virt/acrn/hsm.c | 20 +++++++++++++++-----
> >  1 file changed, 15 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
> > index 5419794fccf1..423ea888d79a 100644
> > --- a/drivers/virt/acrn/hsm.c
> > +++ b/drivers/virt/acrn/hsm.c
> > @@ -136,8 +136,10 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
> >               if (IS_ERR(vm_param))
> >                       return PTR_ERR(vm_param);
> >
> > -             if ((vm_param->reserved0 | vm_param->reserved1) != 0)
> > +             if ((vm_param->reserved0 | vm_param->reserved1) != 0) {
> > +                     kfree(vm_param);
> >                       return -EINVAL;
> > +             }
> >
> >               vm = acrn_vm_create(vm, vm_param);
> >               if (!vm) {
> > @@ -182,21 +184,29 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
> >                       return PTR_ERR(cpu_regs);
> >
> >               for (i = 0; i < ARRAY_SIZE(cpu_regs->reserved); i++)
> > -                     if (cpu_regs->reserved[i])
> > +                     if (cpu_regs->reserved[i]) {
> > +                             kfree(cpu_regs);
> >                               return -EINVAL;
> > +                     }
> >
> >               for (i = 0; i < ARRAY_SIZE(cpu_regs->vcpu_regs.reserved_32); i++)
> > -                     if (cpu_regs->vcpu_regs.reserved_32[i])
> > +                     if (cpu_regs->vcpu_regs.reserved_32[i]) {
> > +                             kfree(cpu_regs);
> >                               return -EINVAL;
> > +                     }
> >
> >               for (i = 0; i < ARRAY_SIZE(cpu_regs->vcpu_regs.reserved_64); i++)
> > -                     if (cpu_regs->vcpu_regs.reserved_64[i])
> > +                     if (cpu_regs->vcpu_regs.reserved_64[i]) {
> > +                             kfree(cpu_regs);
> >                               return -EINVAL;
> > +                     }
> >
> >               for (i = 0; i < ARRAY_SIZE(cpu_regs->vcpu_regs.gdt.reserved); i++)
> >                       if (cpu_regs->vcpu_regs.gdt.reserved[i] |
> > -                         cpu_regs->vcpu_regs.idt.reserved[i])
> > +                         cpu_regs->vcpu_regs.idt.reserved[i]) {
> > +                             kfree(cpu_regs);
> >                               return -EINVAL;
> > +                     }
> >
> >               ret = hcall_set_vcpu_regs(vm->vmid, virt_to_phys(cpu_regs));
> >               if (ret < 0)
> >
> > base-commit: 5859a2b1991101d6b978f3feb5325dad39421f29
> > --
> > 2.25.1
> >
>
> How did you test this?

Ok, thanks.  Firstly there is just some
parameter that should be freed before func returns the -EINVAL error
in the patch. I think it was correct, no need to test it. And
secondly the commitor
Li Fei1 also reviewed the patch code. finally I am sorry that  no arcn
hso hardware to test it.

Regards,
  butt3rflyh4ck.

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