Re: [PATCH] virtio-pci: fix memory leak of vp_dev

[Xianting Tian]

Thanks, I checked this before your reply, it is not a bug,

Sorry for the inconvenience caused.

在 2022/1/7 上午10:34, Jason Wang 写道:
> On Thu, Jan 6, 2022 at 4:31 PM Xianting Tian
> <xianting.tian@xxxxxxxxxxxxxxxxx> wrote:
> > In virtio_pci_probe(), vp_dev will not be freed if it goes to
> > "err_register" branch. fix it
> >
> > Signed-off-by: Xianting Tian <xianting.tian@xxxxxxxxxxxxxxxxx>
> So we had this:
>
> commit 33635bd976fb4c3ccf0cfbb81a8d29bb87760607
> Author: weiping zhang <zhangweiping@xxxxxxxxxxxxxxx>
> Date:   Thu Dec 21 20:40:24 2017 +0800
>
>      virtio_pci: don't kfree device on register failure
>
>      As mentioned at drivers/base/core.c:
>      /*
>       * NOTE: _Never_ directly free @dev after calling this function, even
>       * if it returned an error! Always use put_device() to give up the
>       * reference initialized in this function instead.
>       */
>      so we don't free vp_dev until vp_dev->vdev.dev.release be called.
>
>      Signed-off-by: weiping zhang <zhangweiping@xxxxxxxxxxxxxxx>
>      Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
>      Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
>
> Any reason that the above fix is wrong?
>
> Thanks
>
> > ---
> >   drivers/virtio/virtio_pci_common.c | 3 +--
> >   1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c
> > index fdbde1db5..48b5ac15e 100644
> > --- a/drivers/virtio/virtio_pci_common.c
> > +++ b/drivers/virtio/virtio_pci_common.c
> > @@ -602,8 +602,7 @@ static int virtio_pci_probe(struct pci_dev *pci_dev,
> >   err_enable_device:
> >          if (reg_dev)
> >                  put_device(&vp_dev->vdev.dev);
> > -       else
> > -               kfree(vp_dev);
> > +       kfree(vp_dev);
> >          return rc;
> >   }
> >
> > --
> > 2.17.1