PCI: Avoid potential NULL pointer dereference in pci_scan_bridge
pci_add_new_bus() calls pci_alloc_child_bus() which calls pci_alloc_bus()
that allocates memory dynamically with kzalloc(). The return value of
kzalloc() is the pointer that's eventually returned from
pci_add_new_bus(), so since kzalloc() can fail and return NULL so can
pci_add_new_bus(). Thus we may end up dereferencing a NULL pointer in
drivers/pci/probe.c::pci_scan_bridge(). Seems to me we should test for
this and bail out if it happens rather than crashing.
Also removed some trailing whitespace that bugged me while looking at
this.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index c84900d..44cbbba 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -764,6 +764,8 @@
if (pci_find_bus(pci_domain_nr(bus), max+1))
goto out;
child = pci_add_new_bus(bus, dev, ++max);
+ if (!child)
+ goto out;
buses = (buses & 0xff000000)
| ((unsigned int)(child->primary) << 0)
| ((unsigned int)(child->secondary) << 8)
@@ -777,7 +779,7 @@
buses &= ~0xff000000;
buses |= CARDBUS_LATENCY_TIMER << 24;
}
-
+
/*
* We need to blast all three values with a single write.
*/