From: Andreas Noever Date: Tue, 16 Sep 2014 21:16:02 +0000 (-0600) Subject: PCI: pciehp: Prevent NULL dereference during probe X-Git-Tag: v3.2.65~158 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5581d5a5ad8bde5d8be7f1342d01f74c66b75efc;p=thirdparty%2Fkernel%2Fstable.git PCI: pciehp: Prevent NULL dereference during probe commit bceee4a97eb58bd0e80e39eff11b506ddd9e7ad3 upstream. 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 Signed-off-by: Ben Hutchings --- diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c index 9350af9011a19..dc126a2326484 100644 --- a/drivers/pci/hotplug/pciehp_core.c +++ b/drivers/pci/hotplug/pciehp_core.c @@ -237,6 +237,13 @@ static int pciehp_probe(struct pcie_device *dev) else if (pciehp_acpi_slot_detection_check(dev->port)) 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");