diff --git a/cmds/installd/commands.c b/cmds/installd/commands.c
index 48bccc3..58e7efe 100644
--- a/cmds/installd/commands.c
+++ b/cmds/installd/commands.c
@@ -1711,12 +1711,7 @@
         ALOGE("invalid apk path '%s' (bad prefix)\n", oat_dir);
         return -1;
     }
-    if ((mkdir(oat_dir, S_IRWXU|S_IRWXG|S_IXOTH) < 0) && (errno != EEXIST))  {
-        ALOGE("cannot create dir '%s': %s\n", oat_dir, strerror(errno));
-        return -1;
-    }
-    if (chmod(oat_dir, S_IRWXU|S_IRWXG|S_IXOTH) < 0) {
-        ALOGE("cannot chmod dir '%s': %s\n", oat_dir, strerror(errno));
+    if (fs_prepare_dir(oat_dir, S_IRWXU | S_IRWXG | S_IXOTH, AID_SYSTEM, AID_INSTALL)) {
         return -1;
     }
     if (selinux_android_restorecon(oat_dir, 0)) {
@@ -1724,12 +1719,7 @@
         return -1;
     }
     snprintf(oat_instr_dir, PKG_PATH_MAX, "%s/%s", oat_dir, instruction_set);
-    if ((mkdir(oat_instr_dir, S_IRWXU|S_IRWXG|S_IXOTH) < 0)  && (errno != EEXIST)) {
-        ALOGE("cannot create dir '%s': %s\n", oat_instr_dir, strerror(errno));
-        return -1;
-    }
-    if (chmod(oat_instr_dir, S_IRWXU|S_IRWXG|S_IXOTH) < 0) {
-        ALOGE("cannot chmod dir '%s': %s\n", oat_dir, strerror(errno));
+    if (fs_prepare_dir(oat_instr_dir, S_IRWXU | S_IRWXG | S_IXOTH, AID_SYSTEM, AID_INSTALL)) {
         return -1;
     }
     return 0;