[PATCH 2/4] PCI: pciehp: bail out if pci_hp_add_bridge() fails

From: Nam Cao
Date: Fri May 03 2024 - 15:24:05 EST


If there is no bus number available for the downstream bus of the
hot-plugged bridge, pci_hp_add_bridge() will fail. The driver proceeds
regardless, and the kernel crashes.

Abort if pci_hp_add_bridge() fails.

Fixes: 0eb3bcfd088e ("[PATCH] pciehp: allow bridged card hotplug")
Signed-off-by: Nam Cao <namcao@xxxxxxxxxxxxx>
Cc: Rajesh Shah <rajesh.shah@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
---
drivers/pci/hotplug/pciehp_pci.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index ad12515a4a12..faf4fcf2fbdf 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -58,8 +58,13 @@ int pciehp_configure_device(struct controller *ctrl)
goto out;
}

- for_each_pci_bridge(dev, parent)
- pci_hp_add_bridge(dev);
+ for_each_pci_bridge(dev, parent) {
+ if (pci_hp_add_bridge(dev)) {
+ pci_stop_and_remove_bus_device(dev);
+ ret = -EINVAL;
+ goto out;
+ }
+ }

pci_assign_unassigned_bridge_resources(bridge);
pcie_bus_configure_settings(parent);
--
2.39.2