From: Andreas Noever Date: Tue, 16 Sep 2014 21:16:02 +0000 (-0600) Subject: PCI: pciehp: Prevent NULL dereference during probe X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=bceee4a97eb5;p=deliverable%2Flinux.git 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 Signed-off-by: Bjorn Helgaas CC: stable@vger.kernel.org # v3.2+ --- diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c index 07aa722bb12c..3a5e7e28b874 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");