[POWERPC] CELLEB: Fix possible NULL pointer dereference

This adds checking for NULL returned value from of_get_property to
prevent possible NULL pointer dereference in the case when expected
properties are not present.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/platforms/celleb/pci.c

@@ -138,8 +138,6 @@ static void celleb_config_read_fake(unsigned char *config, int where,
 		*val = celleb_fake_config_readl(p);
 		break;
 	}
-
-	return;
 }
 
 static void celleb_config_write_fake(unsigned char *config, int where,
@@ -158,7 +156,6 @@ static void celleb_config_write_fake(unsigned char *config, int where,
 		celleb_fake_config_writel(val, p);
 		break;
 	}
-	return;
 }
 
 static int celleb_fake_pci_read_config(struct pci_bus *bus,
@@ -351,6 +348,10 @@ static int __init celleb_setup_fake_pci_device(struct device_node *node,
 	wi1 = of_get_property(node, "vendor-id", NULL);
 	wi2 = of_get_property(node, "class-code", NULL);
 	wi3 = of_get_property(node, "revision-id", NULL);
+	if (!wi0 || !wi1 || !wi2 || !wi3) {
+		printk(KERN_ERR "PCI: Missing device tree properties.\n");
+		goto error;
+	}
 
 	celleb_config_write_fake(*config, PCI_DEVICE_ID, 2, wi0[0] & 0xffff);
 	celleb_config_write_fake(*config, PCI_VENDOR_ID, 2, wi1[0] & 0xffff);
@@ -372,6 +373,10 @@ static int __init celleb_setup_fake_pci_device(struct device_node *node,
 	celleb_setup_pci_base_addrs(hose, devno, fn, num_base_addr);
 
 	li = of_get_property(node, "interrupts", &rlen);
+	if (!li) {
+		printk(KERN_ERR "PCI: interrupts not found.\n");
+		goto error;
+	}
 	val = li[0];
 	celleb_config_write_fake(*config, PCI_INTERRUPT_PIN, 1, 1);
 	celleb_config_write_fake(*config, PCI_INTERRUPT_LINE, 1, val);