[PATCH 4.18 15/22] PCI: hotplug: Dont leak pci_slot on registration failure

Greg Kroah-Hartman
2018-08-23T09:11:04Z

From: Lukas Wunner <lukas@wunner.de>

commit 4ce6435820d1f1cc2c2788e232735eb244bcc8a3 upstream.

If addition of sysfs files fails on registration of a hotplug slot, the
struct pci_slot as well as the entry in the slot_list is leaked. The
issue has been present since the hotplug core was introduced in 2002:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Perhaps the idea was that even though sysfs addition fails, the slot
should still be usable. But that's not how drivers use the interface,
they abort probe if a non-zero value is returned.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v2.4.15+
Cc: Greg Kroah-Hartman <greg@kroah.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/pci/hotplug/pci_hotplug_core.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/drivers/pci/hotplug/pci_hotplug_core.c
+++ b/drivers/pci/hotplug/pci_hotplug_core.c
@@ -438,8 +438,17 @@ int __pci_hp_register(struct hotplug_slo
list_add(&slot->slot_list, &pci_hotplug_slot_list);

result = fs_add_slot(pci_slot);
+ if (result)
+ goto err_list_del;
+
kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
dbg("Added slot %s to the list\n", name);
+ goto out;
+
+err_list_del:
+ list_del(&slot->slot_list);
+ pci_slot->hotplug = NULL;
+ pci_destroy_slot(pci_slot);
out:
mutex_unlock(&pci_hp_mutex);
return result;