Re: [PATCH v2] ACPI / hotplug / PCI: fix memory leak in enable_slot()

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Apr 08, 2021 at 05:18:46PM +0200, Rafael J. Wysocki wrote:
> On Thu, Mar 25, 2021 at 8:27 AM Zhiqiang Liu <liuzhiqiang26@huawei.com> wrote:
> >
> > From: Feilong Lin <linfeilong@huawei.com>
> >
> > In enable_slot() in drivers/pci/hotplug/acpiphp_glue.c, if pci_get_slot()
> > will return NULL, we will do not set SLOT_ENABLED flag of slot. if one
> > device is found by calling pci_get_slot(), its reference count will be
> > increased. In this case, we did not call pci_dev_put() to decrement the
> > its reference count, the memory of the device (struct pci_dev type) will
> > leak.
> >
> > Fix it by calling pci_dev_put() to decrement its reference count after that
> > pci_get_slot() returns a PCI device.
> >
> > Signed-off-by: Feilong Lin <linfeilong@huawei.com>
> > Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
> > --
> > v2: rewrite subject and commit log as suggested by Bjorn Helgaas.
> 
> The fix is correct AFAICS, so
> 
> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> Bjorn, has this been applied already?  If not, do you want me to take
> it or are you going to queue it up yourself?

I'll pick it up; thanks for the review and the reminder!

> > ---
> >  drivers/pci/hotplug/acpiphp_glue.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
> > index 3365c93abf0e..f031302ad401 100644
> > --- a/drivers/pci/hotplug/acpiphp_glue.c
> > +++ b/drivers/pci/hotplug/acpiphp_glue.c
> > @@ -533,6 +533,7 @@ static void enable_slot(struct acpiphp_slot *slot, bool bridge)
> >                         slot->flags &= ~SLOT_ENABLED;
> >                         continue;
> >                 }
> > +               pci_dev_put(dev);
> >         }
> >  }
> >
> > --
> > 2.19.1
> >