From: Jiri Slaby Date: Wed, 9 Jun 2010 20:31:13 +0000 (+0200) Subject: PCI: hotplug/cpqphp, fix NULL dereference X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a7ef7d1f5e898984c479e8c41ca702141bbadc78;p=linux-beck.git PCI: hotplug/cpqphp, fix NULL dereference There are devices out there which are PCI Hot-plug controllers with compaq PCI IDs, but are not bridges, hence have pdev->subordinate NULL. But cpqphp expects the pointer to be non-NULL. Add a check to the probe function to avoid oopses like: BUG: unable to handle kernel NULL pointer dereference at 00000050 IP: [] cpqhpc_probe+0x951/0x1120 [cpqphp] *pdpt = 0000000033779001 *pde = 0000000000000000 ... The device here was: 00:0b.0 PCI Hot-plug controller [0804]: Compaq Computer Corporation PCI Hotplug Controller [0e11:a0f7] (rev 11) Subsystem: Compaq Computer Corporation Device [0e11:a2f8] Signed-off-by: Jiri Slaby Cc: Greg KH Signed-off-by: Jesse Barnes --- diff --git a/drivers/pci/hotplug/cpqphp_core.c b/drivers/pci/hotplug/cpqphp_core.c index b3e5580c837b..4952c3b9379d 100644 --- a/drivers/pci/hotplug/cpqphp_core.c +++ b/drivers/pci/hotplug/cpqphp_core.c @@ -828,7 +828,14 @@ static int cpqhpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent) pci_name(pdev), err); return err; } + bus = pdev->subordinate; + if (!bus) { + dev_notice(&pdev->dev, "the device is not a bridge, " + "skipping\n"); + rc = -ENODEV; + goto err_disable_device; + } /* Need to read VID early b/c it's used to differentiate CPQ and INTC * discovery