This is a note to let you know that I've just added the patch titled ACPI / hotplug / PCI: Fix reference count leak in enable_slot() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: acpi-hotplug-pci-fix-reference-count-leak-in-enable_.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 9b8bc03821e7e0ed040bc0c2afce25afbab13337 Author: Feilong Lin <linfeilong@xxxxxxxxxx> Date: Thu Mar 25 15:26:00 2021 +0800 ACPI / hotplug / PCI: Fix reference count leak in enable_slot() [ Upstream commit 3bbfd319034ddce59e023837a4aa11439460509b ] In enable_slot(), if pci_get_slot() returns NULL, we clear the SLOT_ENABLED flag. When pci_get_slot() finds a device, it increments the device's reference count. In this case, we did not call pci_dev_put() to decrement the reference count, so the memory of the device (struct pci_dev type) will eventually leak. Call pci_dev_put() to decrement its reference count when pci_get_slot() returns a PCI device. Link: https://lore.kernel.org/r/b411af88-5049-a1c6-83ac-d104a1f429be@xxxxxxxxxx Signed-off-by: Feilong Lin <linfeilong@xxxxxxxxxx> Signed-off-by: Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index 6727471ea5b4..d0f5c526c8e6 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -538,6 +538,7 @@ static void enable_slot(struct acpiphp_slot *slot) slot->flags &= (~SLOT_ENABLED); continue; } + pci_dev_put(dev); } }