X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=udev%2Fudev-event.c;h=32b45e9baca6c039932b4b875b4b03b15425d9a7;hb=310119085123384a1620f23f6bcd3b26645a70be;hp=2d513d7b656b00abd44cf03d5f923306e9b328e9;hpb=92f4313665bc726baf055f81e2daae48c77123fc;p=elogind.git

diff --git a/udev/udev-event.c b/udev/udev-event.c
index 2d513d7b6..32b45e9ba 100644
--- a/udev/udev-event.c
+++ b/udev/udev-event.c
@@ -231,8 +231,9 @@ found:
 			break;
 		case SUBST_DRIVER:
 			if (event->dev_parent != NULL) {
-				const char *driver = udev_device_get_driver(event->dev_parent);
+				const char *driver;
 
+				driver = udev_device_get_driver(event->dev_parent);
 				if (driver == NULL)
 					break;
 				util_strlcat(string, driver, maxsize);
@@ -394,13 +395,16 @@ found:
 			break;
 		case SUBST_LINKS:
 			{
+				size_t devlen = strlen(udev_get_dev_path(event->udev))+1;
 				struct udev_list_entry *list_entry;
 
 				list_entry = udev_device_get_devlinks_list_entry(dev);
-				util_strlcat(string, udev_list_entry_get_name(list_entry), maxsize);
+				if (list_entry == NULL)
+					break;
+				util_strlcat(string, &udev_list_entry_get_name(list_entry)[devlen], maxsize);
 				udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry)) {
 					util_strlcat(string, " ", maxsize);
-					util_strlcat(string, udev_list_entry_get_name(list_entry), maxsize);
+					util_strlcat(string, &udev_list_entry_get_name(list_entry)[devlen], maxsize);
 				}
 			}
 			break;
@@ -425,6 +429,8 @@ found:
 				if (list_entry == NULL)
 					break;
 				value = udev_list_entry_get_value(list_entry);
+				if (value == NULL)
+					break;
 				dbg(event->udev, "substitute env '%s=%s'\n", attr, value);
 				util_strlcat(string, value, maxsize);
 				break;