Hello,

syzbot found the following issue on:

HEAD commit: 8653b778 Merge tag 'clk-for-linus' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=109531a3500000 kernel config: https://syzkaller.appspot.com/x/.config?x=98408202fed1f636 dashboard link: https://syzkaller.appspot.com/bug?extid=92e45ae45543f89e8c88 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1421ec47500000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12bfa077500000

IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+92e45ae45543f89e8c88@syzkaller.appspotmail.com

usb 1-1: config 0 interface 0 altsetting 0 bulk endpoint 0x8A has invalid maxpacket 31 usb 1-1: New USB device found, idVendor=324b, idProduct=5963, bcdDevice= 0.d2 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 usb 1-1: config 0 descriptor?? usb 1-1: MIDIStreaming interface descriptor not found ================================================================================ UBSAN: shift-out-of-bounds in sound/usb/midi.c:1928:8 shift exponent 244 is too large for 32-bit type 'int' CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:395 snd_usbmidi_get_ms_info.cold+0x83/0xd4 sound/usb/midi.c:1928 __snd_usbmidi_create+0x380/0x2320 sound/usb/midi.c:2404 snd_usb_create_quirk+0xa5/0xe0 sound/usb/quirks.c:562 usb_audio_probe+0x623/0x2ab0 sound/usb/card.c:795

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