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

From: Rafael J. Wysocki
Date: Thu Apr 08 2021 - 11:19:08 EST


On Thu, Mar 25, 2021 at 8:27 AM Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx> wrote:
>
> From: Feilong Lin <linfeilong@xxxxxxxxxx>
>
> 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@xxxxxxxxxx>
> Signed-off-by: Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx>
> --
> 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@xxxxxxxxx>

Bjorn, has this been applied already? If not, do you want me to take
it or are you going to queue it up yourself?

> ---
> 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
>