[ 072/108] PCI: acpiphp: check whether _ADR evaluation succeeded

Ben Hutchings
2012-10-07T23:38:21Z

From: Bjorn Helgaas <bhelgaas@google.com>

commit dfb117b3e50c52c7b3416db4a4569224b8db80bb upstream.

Check whether we evaluated _ADR successfully. Previously we ignored
failure, so we would have used garbage data from the stack as the device
and function number.

We return AE_OK so that we ignore only this slot and continue looking
for other slots.

Found by Coverity (CID 113981).

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/pci/hotplug/acpiphp_glue.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 806c44f..09bf377 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -132,6 +132,15 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
if (!acpi_pci_check_ejectable(pbus, handle) && !is_dock_device(handle))
return AE_OK;

+ status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
+ if (ACPI_FAILURE(status)) {
+ warn("can't evaluate _ADR (%#x)\n", status);
+ return AE_OK;
+ }
+
+ device = (adr >> 16) & 0xffff;
+ function = adr & 0xffff;
+
pdev = pbus->self;
if (pdev && pci_is_pcie(pdev)) {
tmp = acpi_find_root_bridge_handle(pdev);
@@ -144,10 +153,6 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
}
}

- acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
- device = (adr >> 16) & 0xffff;
- function = adr & 0xffff;
-
newfunc = kzalloc(sizeof(struct acpiphp_func), GFP_KERNEL);
if (!newfunc)
return AE_NO_MEMORY;