PCI: Fix refcount issue in pci_create_root_bus() error recovery path

After calling device_register(&bridge->dev), the bridge is reference-
counted, and it is illegal to call kfree() on it except in the release
function.

[bhelgaas: changelog, use put_device() after device_register() failure]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index ed5ce185eed9..15c39cb09619 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1711,12 +1711,16 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
         bridge->dev.release = pci_release_bus_bridge_dev;
         dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
         error = pcibios_root_bridge_prepare(bridge);
-        if (error)
-                goto bridge_dev_reg_err;
+        if (error) {
+                kfree(bridge);
+                goto err_out;
+        }
 
         error = device_register(&bridge->dev);
-        if (error)
-                goto bridge_dev_reg_err;
+        if (error) {
+                put_device(&bridge->dev);
+                goto err_out;
+        }
         b->bridge = get_device(&bridge->dev);
         device_enable_async_suspend(b->bridge);
         pci_set_bus_of_node(b);
@@ -1772,8 +1776,6 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
 class_dev_reg_err:
         put_device(&bridge->dev);
         device_unregister(&bridge->dev);
-bridge_dev_reg_err:
-        kfree(bridge);
 err_out:
         kfree(b);
         return NULL;