msc host: end the interface's configuration when Get Max LUN fails to submit

src/class/msc/msc_host.c

diff --git a/src/class/msc/msc_host.c b/src/class/msc/msc_host.c
index 051aa6a..1ba371c 100644
--- a/src/class/msc/msc_host.c
+++ b/src/class/msc/msc_host.c
@@ -466,7 +466,11 @@
       .complete_cb = config_get_maxlun_complete,
       .user_data    = 0
   };
-  TU_ASSERT(tuh_control_xfer(&xfer));
+  // usbh ignores set_config's result: report completion here or the enumeration never ends
+  if (!tuh_control_xfer(&xfer)) {
+    config_abort(daddr);
+    return false;
+  }
 
   return true;
 }

test/unit-test/test/host/msc/test_msc_host.c

diff --git a/test/unit-test/test/host/msc/test_msc_host.c b/test/unit-test/test/host/msc/test_msc_host.c
index b4b92c6..daf6038 100644
--- a/test/unit-test/test/host/msc/test_msc_host.c
+++ b/test/unit-test/test/host/msc/test_msc_host.c
@@ -27,6 +27,7 @@
 static uint8_t  set_config_count;
 static msc_csw_t complete_csw;
 static bool     retry_submitted;
+static bool     ctrl_xfer_fail;
 static tuh_xfer_cb_t ctrl_complete_cb;
 static uint8_t  enum_buf[64];
 static uint8_t  data[98304];
@@ -39,7 +40,7 @@
 
 bool tuh_control_xfer(tuh_xfer_t *xfer) {
   ctrl_complete_cb = xfer->complete_cb;
-  return true;
+  return !ctrl_xfer_fail;
 }
 
 uint8_t *usbh_get_enum_buf(void) {
@@ -96,7 +97,7 @@
   return true;
 }
 
-static void mount_bot_interface(void) {
+static void open_bot_interface(void) {
   struct TU_ATTR_PACKED {
     tusb_desc_interface_t itf;
     tusb_desc_endpoint_t  ep_out;
@@ -109,6 +110,10 @@
   };
 
   TEST_ASSERT_EQUAL(sizeof(desc), msch_open(0, DADDR, &desc.itf, sizeof(desc)));
+}
+
+static void mount_bot_interface(void) {
+  open_bot_interface();
   TEST_ASSERT_TRUE(msch_set_config(DADDR, 0));
 }
 
@@ -153,6 +158,7 @@
   complete_count  = 0;
   set_config_count = 0;
   retry_submitted = false;
+  ctrl_xfer_fail  = false;
   msch_init();
   mount_bot_interface();
 }
@@ -336,6 +342,17 @@
   assert_enum_ended_unmounted(4);
 }
 
+// usbh ignores set_config's result, so a Get Max LUN that fails to submit must end the configuration itself
+void test_msc_host_enum_get_max_lun_submit_fail(void) {
+  msch_close(DADDR);
+  set_config_count = 0;
+  ctrl_xfer_fail   = true;
+  open_bot_interface();
+  (void) msch_set_config(DADDR, 0);
+
+  assert_enum_ended_unmounted(0);
+}
+
 // usbh closes the driver before failing the in-flight Get Max LUN, and has already ended the enumeration
 void test_msc_host_enum_unplug_during_get_max_lun(void) {
   msch_close(DADDR);