libudev: enumerate: fix NULL-deref for subsystem-matches

[elogind.git] / src / libudev / libudev-enumerate.c

diff --git a/src/libudev/libudev-enumerate.c b/src/libudev/libudev-enumerate.c
index 3e791074f39b7235e5542209bd3808a67251b9ba..385829d464345bf96705c358e9f26152f725f96d 100644 (file)
--- a/src/libudev/libudev-enumerate.c
+++ b/src/libudev/libudev-enumerate.c
@@ -721,6 +721,8 @@ static bool match_subsystem(struct udev_enumerate *udev_enumerate, const char *s
 {
         struct udev_list_entry *list_entry;
 
+        subsystem = subsystem ? : "";
+
         udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_nomatch_list)) {
                 if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
                         return false;
@@ -829,23 +831,27 @@ nomatch:
 static int parent_add_child(struct udev_enumerate *enumerate, const char *path)
 {
         struct udev_device *dev;
+        int r = 0;
 
         dev = udev_device_new_from_syspath(enumerate->udev, path);
         if (dev == NULL)
                 return -ENODEV;
 
         if (!match_subsystem(enumerate, udev_device_get_subsystem(dev)))
-                return 0;
+                goto nomatch;
         if (!match_sysname(enumerate, udev_device_get_sysname(dev)))
-                return 0;
+                goto nomatch;
         if (!match_property(enumerate, dev))
-                return 0;
+                goto nomatch;
         if (!match_sysattr(enumerate, dev))
-                return 0;
+                goto nomatch;
 
         syspath_add(enumerate, udev_device_get_syspath(dev));
+        r = 1;
+
+nomatch:
         udev_device_unref(dev);
-        return 1;
+        return r;
 }
 
 static int parent_crawl_children(struct udev_enumerate *enumerate, const char *path, int maxdepth)