Index: lib/vlog.c
===================================================================
--- lib/vlog.c.orig
+++ lib/vlog.c
@@ -227,7 +227,7 @@ set_facility_level(enum vlog_facility fa
     ovs_mutex_lock(&log_file_mutex);
     if (!module) {
         struct vlog_module *mp;
-        LIST_FOR_EACH (mp, list, &vlog_modules) {
+        LIST_FOR_EACH_CHECK (mp, list, &vlog_modules) {
             mp->levels[facility] = level;
             update_min_level(mp);
         }
@@ -347,7 +347,7 @@ vlog_set_log_file(const char *file_name)
         log_writer = async_append_create(new_log_fd);
     }
 
-    LIST_FOR_EACH (mp, list, &vlog_modules) {
+    LIST_FOR_EACH_CHECK (mp, list, &vlog_modules) {
         update_min_level(mp);
     }
     ovs_mutex_unlock(&log_file_mutex);
Index: lib/list.h
===================================================================
--- lib/list.h.orig
+++ lib/list.h
@@ -79,5 +79,9 @@ bool list_is_short(const struct list *);
           ? ASSIGN_CONTAINER(NEXT, (ITER)->MEMBER.next, MEMBER), 1 \
           : 0);                                                    \
          (ITER) = (NEXT))
+#define LIST_FOR_EACH_CHECK(ITER, MEMBER, LIST)                                      \
+    for (ASSIGN_CONTAINER(ITER, (LIST)->next, MEMBER);                               \
+         &(ITER)->MEMBER != (LIST) && (ITER)->MEMBER.next != (ITER)->MEMBER.prev;    \
+         ASSIGN_CONTAINER(ITER, (ITER)->MEMBER.next, MEMBER))
 
 #endif /* list.h */