pci_enable_obff() and pci_enable_ltr() incorrectly check "dev->bus" instead of "dev->bus->self" to determine whether the upstream device is a P2P bridge or a host bridge. For devices on the root bus, the upstream device is a host bridge, "dev->bus != NULL" and "dev->bus->self == NULL", and we panic with a null pointer dereference. These functions should previously have panicked when called on devices supporting OBFF or LTR, so they should be regarded as untested. Found by Coverity (CID 143038 and CID 143039). Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- drivers/pci/pci.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 8f4a5ea..b9e93cf 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2108,7 +2108,7 @@ int pci_enable_obff(struct pci_dev *dev, enum pci_obff_signal_type type) return -ENOTSUPP; /* no OBFF support at all */ /* Make sure the topology supports OBFF as well */ - if (dev->bus) { + if (dev->bus->self) { ret = pci_enable_obff(dev->bus->self, type); if (ret) return ret; @@ -2215,7 +2215,7 @@ int pci_enable_ltr(struct pci_dev *dev) return -EINVAL; /* Enable upstream ports first */ - if (dev->bus) { + if (dev->bus->self) { ret = pci_enable_ltr(dev->bus->self); if (ret) return ret; -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html