Avoid using configuration 5

- this fixes setting configuration for iOS 11 devices inside virtual machines which caused timeout and subsequent reboot of the device when unplugged from USB

1 files changed, 8 insertions, 4 deletions

diff --git a/src/usb.c b/src/usb.c
index b659d90..364930c 100644
--- a/src/usb.c
+++ b/src/usb.c
@@ -392,13 +392,17 @@ static int usb_device_add(libusb_device* dev)
                 return -1;
         }
 
+        int desired_config = devdesc.bNumConfigurations;
+        if (desired_config > 4) {
+                desired_config = 4;
+        }
         int current_config = 0;
         if((res = libusb_get_configuration(handle, &current_config)) != 0) {
                 usbmuxd_log(LL_WARNING, "Could not get configuration for device %d-%d: %d", bus, address, res);
                 libusb_close(handle);
                 return -1;
         }
-        if (current_config != devdesc.bNumConfigurations) {
+        if (current_config != desired_config) {
                 struct libusb_config_descriptor *config;
                 if((res = libusb_get_active_config_descriptor(dev, &config)) != 0) {
                         usbmuxd_log(LL_NOTICE, "Could not get old configuration descriptor for device %d-%d: %d", bus, address, res);
@@ -420,9 +424,9 @@ static int usb_device_add(libusb_device* dev)
                         libusb_free_config_descriptor(config);
                 }
 
-                usbmuxd_log(LL_INFO, "Setting configuration for device %d-%d, from %d to %d", bus, address, current_config, devdesc.bNumConfigurations);
-                if((res = libusb_set_configuration(handle, devdesc.bNumConfigurations)) != 0) {
-                        usbmuxd_log(LL_WARNING, "Could not set configuration %d for device %d-%d: %d", devdesc.bNumConfigurations, bus, address, res);
+                usbmuxd_log(LL_INFO, "Setting configuration for device %d-%d, from %d to %d", bus, address, current_config, desired_config);
+                if((res = libusb_set_configuration(handle, desired_config)) != 0) {
+                        usbmuxd_log(LL_WARNING, "Could not set configuration %d for device %d-%d: %d", desired_config, bus, address, res);
                         libusb_close(handle);
                         return -1;
                 }