From bceee4a97eb58bd0e80e39eff11b506ddd9e7ad3 Mon Sep 17 00:00:00 2001
From: Andreas Noever <andreas.noever@gmail.com>
Date: Tue, 16 Sep 2014 15:16:02 -0600
Subject: [PATCH] PCI: pciehp: Prevent NULL dereference during probe
pciehp assumes that dev->subordinate, the struct pci_bus for a bridge's
secondary bus, exists. But we do not create that bus if we run out of bus
numbers during enumeration. This leads to a NULL dereference in
init_slot() (and other places).
Change pciehp_probe() to return -ENODEV when no secondary bus is present.
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v3.2+
---
drivers/pci/hotplug/pciehp_core.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 07aa722bb12cd..3a5e7e28b8740 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -262,6 +262,13 @@ static int pciehp_probe(struct pcie_device *dev)
goto err_out_none;
}
+ if (!dev->port->subordinate) {
+ /* Can happen if we run out of bus numbers during probe */
+ dev_err(&dev->device,
+ "Hotplug bridge without secondary bus, ignoring\n");
+ goto err_out_none;
+ }
+
ctrl = pcie_init(dev);
if (!ctrl) {
dev_err(&dev->device, "Controller initialization failed\n");
--
2.30.2