Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e29d895b authored by Febin Thattil's avatar Febin Thattil
Browse files

Handle null accessory strings safely 

In certain misconfigured car head units, ACCESSORY START UEVENT is
delivered again, while former ACCESSORY START UEVENT was already
configured. This leads to null accessory strings being passed to the
accessory mode, which expect the manufacturer and model strings to be
non-null. This causes a platform reset. This change gracefully handles
the case of expected non-null accessory strings being null by not
updating the USB Accessory for the same.

Bug: 275263867
Bug: 356421183
Flag: EXEMPT bugfix
Change-Id: I108b46ff164877d92d4e8fb6d53beca230df4fa0
parent 074c4921

services/usb/java/com/android/server/usb/UsbDeviceManager.java

+31 −22
Original line number Diff line number Diff line
@@ -874,10 +874,16 @@ public class UsbDeviceManager implements ActivityTaskManagerInternal.ScreenObser 
                // successfully entered accessory mode

                String[] accessoryStrings = mUsbDeviceManager.getAccessoryStrings();

                if (accessoryStrings != null) {

                    UsbSerialReader serialReader = new UsbSerialReader(mContext, mPermissionManager,

                    if (accessoryStrings[UsbAccessory.MANUFACTURER_STRING] != null

                            && accessoryStrings[UsbAccessory.MODEL_STRING] != null) {

                        UsbSerialReader serialReader =

                                new UsbSerialReader(

                                        mContext,

                                        mPermissionManager,

                                        accessoryStrings[UsbAccessory.SERIAL_STRING]);



                    mCurrentAccessory = new UsbAccessory(

                        mCurrentAccessory =

                                new UsbAccessory(

                                        accessoryStrings[UsbAccessory.MANUFACTURER_STRING],

                                        accessoryStrings[UsbAccessory.MODEL_STRING],

                                        accessoryStrings[UsbAccessory.DESCRIPTION_STRING],
@@ -897,6 +903,9 @@ public class UsbDeviceManager implements ActivityTaskManagerInternal.ScreenObser 
                        if (Flags.checkUserActionUnlocked() && mUserUnlockedAfterBoot) {

                            attachAccessory();

                        } // else handle in boot completed

                    } else {

                        Slog.e(TAG, "expected non-null accessory strings are null");

                    }

                } else {

                    Slog.e(TAG, "nativeGetAccessoryStrings failed");

                }