diff --git a/Makefile-tests.am b/Makefile-tests.am
index 955cef17..68dcb9b0 100644
--- a/Makefile-tests.am
+++ b/Makefile-tests.am
@@ -113,6 +113,12 @@ insttest_SCRIPTS += tests/test-core.js \
 testmeta_DATA += test-core.test test-sizes.test test-sysroot.test
 endif
 
+insttest_LTLIBRARIES = libreaddir-rand.la
+libreaddir_rand_la_SOURCES = tests/readdir-rand.c
+libreaddir_rand_la_CFLAGS = $(OT_INTERNAL_GIO_UNIX_CFLAGS)
+libreaddir_rand_la_LIBADD = $(OT_INTERNAL_GIO_UNIX_LIBS)
+libreaddir_rand_la_LDFLAGS = -avoid-version
+
 endif
 
 # "make check" do not depend from --enable-installed-tests
diff --git a/tests/libtest.sh b/tests/libtest.sh
index ba435c09..b788bc97 100644
--- a/tests/libtest.sh
+++ b/tests/libtest.sh
@@ -39,6 +39,8 @@ fi
 
 if test -n "$OT_TESTS_VALGRIND"; then
     CMD_PREFIX="env G_SLICE=always-malloc valgrind -q --leak-check=full --num-callers=30 --suppressions=${SRCDIR}/ostree-valgrind.supp"
+else
+    CMD_PREFIX="env LD_PRELOAD=${SRCDIR}/libreaddir-rand.so"
 fi
 
 assert_not_reached () {
diff --git a/tests/readdir-rand.c b/tests/readdir-rand.c
new file mode 100644
index 00000000..70a001fe
--- /dev/null
+++ b/tests/readdir-rand.c
@@ -0,0 +1,124 @@
+#define _GNU_SOURCE
+#include <dirent.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <dlfcn.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <glib.h>
+
+struct linux_dirent {
+  long           d_ino;
+  off_t          d_off;
+  unsigned short d_reclen;
+  char           d_name[];
+};
+
+#define BUF_SIZE 1024
+
+static GHashTable *direntcache;
+static GMutex direntcache_lock;
+static gsize initialized;
+
+typedef struct {
+  GPtrArray *entries;
+  guint offset;
+} DirEntries;
+
+static void
+dir_entries_free (gpointer data)
+{
+  DirEntries *d = data;
+  g_ptr_array_unref (d->entries);
+  g_free (d);
+}
+
+static DirEntries *
+dir_entries_new (void)
+{
+  DirEntries *d = g_new0 (DirEntries, 1);
+  d->entries = g_ptr_array_new_with_free_func (g_free);
+  return d;
+}
+
+static void
+ensure_initialized (void)
+{
+  if (g_once_init_enter (&initialized))
+    {
+      direntcache = g_hash_table_new_full (NULL, NULL, NULL, dir_entries_free);
+      g_mutex_init (&direntcache_lock);
+      g_once_init_leave (&initialized, 1);
+    }
+}
+
+struct dirent *
+readdir (DIR *dirp)
+{
+  struct dirent *(*real_readdir)(DIR *dirp) = dlsym (RTLD_NEXT, "readdir");
+  struct dirent *ret;
+  gboolean doloop = TRUE;
+  
+  ensure_initialized ();
+
+  while (doloop)
+    {
+      DirEntries *de;
+      GSList *l;
+
+      errno = 0;
+      ret = real_readdir (dirp);
+      if (ret == NULL && errno != 0)
+	goto out;
+
+      g_mutex_lock (&direntcache_lock);
+      de = g_hash_table_lookup (direntcache, dirp);
+      if (ret)
+	{
+	  if (g_random_boolean ())
+	    {
+	      if (!de)
+		{
+		  de = dir_entries_new ();
+		  g_hash_table_insert (direntcache, dirp, de);
+		}
+	      struct dirent *copy;
+	      copy = g_memdup (ret, sizeof (struct dirent));
+	      g_ptr_array_add (de->entries, copy);
+	    }
+	  else
+	    {
+	      doloop = FALSE;
+	    }
+	}
+      else
+	{
+	  if (de && de->offset < de->entries->len)
+	    {
+	      ret = de->entries->pdata[de->offset];
+	      de->offset++;
+	    }
+	  doloop = FALSE;
+	}
+      g_mutex_unlock (&direntcache_lock);
+    }
+  
+ out:
+  return ret;
+}
+
+int
+closedir (DIR *dirp)
+{
+  int (*real_closedir)(DIR *dirp) = dlsym (RTLD_NEXT, "closedir");
+
+  ensure_initialized ();
+  
+  g_mutex_lock (&direntcache_lock);
+  g_hash_table_remove (direntcache, dirp);
+  g_mutex_unlock (&direntcache_lock);
+
+  return real_closedir (dirp);
+}