WARNING in sysfs_create_file_ns

[syzbot <syzbot+5b9bba68c833c84a1135@syzkaller.appspotmail.com>]

Hello,

syzbot found the following crash on:

HEAD commit:    7829a896 usb-fuzzer: main usb gadget fuzzer driver
git tree:       https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=12119440600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f6d4561982f71f63
dashboard link: https://syzkaller.appspot.com/bug?extid=5b9bba68c833c84a1135
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1486787fa00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11aa97d8600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+5b9bba68c833c84a1135@syzkaller.appspotmail.com

usbvision_audio_off: can't write reg
usb 1-1: usbvision_write_reg: failed: error -2
usb 1-1: usbvision_write_reg: failed: error -2
usb 1-1: usbvision_write_reg: failed: error -2
usb 1-1: usbvision_write_reg: failed: error -2
usb 1-1: usbvision_write_reg: failed: error -2
usbvision_i2c_register: can't write reg
videodev: could not get a free minor
usb 1-1: USBVision[129]: video_register_device() failed
WARNING: CPU: 1 PID: 22 at fs/sysfs/file.c:327  
sysfs_create_file_ns+0x13c/0x1c0 fs/sysfs/file.c:327
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 22 Comm: kworker/1:1 Not tainted 5.2.0-rc6+ #13
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:77 [inline]
  dump_stack+0xca/0x13e lib/dump_stack.c:113
  panic+0x292/0x6c9 kernel/panic.c:219
  __warn.cold+0x20/0x4b kernel/panic.c:576
  report_bug+0x262/0x2a0 lib/bug.c:186
  fixup_bug arch/x86/kernel/traps.c:179 [inline]
  fixup_bug arch/x86/kernel/traps.c:174 [inline]
  do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272
  do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291
  invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:986
RIP: 0010:sysfs_create_file_ns+0x13c/0x1c0 fs/sysfs/file.c:327
Code: 85 82 00 00 00 41 55 48 8b 7b 30 31 d2 48 89 ee 44 8b 4c 24 50 44 8b  
44 24 40 e8 af f9 ff ff 41 89 c5 58 eb 0d e8 54 85 b6 ff <0f> 0b 41 bd ea  
ff ff ff e8 47 85 b6 ff 44 89 e8 48 ba 00 00 00 00
RSP: 0018:ffff8881d9f97130 EFLAGS: 00010293
RAX: ffff8881d9f88000 RBX: ffff8881cbb0a490 RCX: ffffffff8266f244
RDX: 0000000000000000 RSI: ffffffff8186565c RDI: ffff8881cbb0a490
RBP: ffffffff8779e1a0 R08: ffff8881d9f88000 R09: ffffed103b665d30
R10: ffffed103b665d2f R11: ffff8881db32e97f R12: 1ffff1103b3f2e27
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8881cbb0a4c0
  sysfs_create_file include/linux/sysfs.h:513 [inline]
  device_create_file+0xe6/0x1d0 drivers/base/core.c:1559
  usbvision_create_sysfs drivers/media/usb/usbvision/usbvision-video.c:252  
[inline]
  usbvision_probe.cold+0x1a73/0x1d69  
drivers/media/usb/usbvision/usbvision-video.c:1530
  usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
  really_probe+0x281/0x660 drivers/base/dd.c:509
  driver_probe_device+0x104/0x210 drivers/base/dd.c:670
  __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
  bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
  __device_attach+0x217/0x360 drivers/base/dd.c:843
  bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
  device_add+0xae6/0x16f0 drivers/base/core.c:2111
  usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
  generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
  usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
  really_probe+0x281/0x660 drivers/base/dd.c:509
  driver_probe_device+0x104/0x210 drivers/base/dd.c:670
  __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
  bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
  __device_attach+0x217/0x360 drivers/base/dd.c:843
  bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
  device_add+0xae6/0x16f0 drivers/base/core.c:2111
  usb_new_device.cold+0x8c1/0x1016 drivers/usb/core/hub.c:2534
  hub_port_connect drivers/usb/core/hub.c:5089 [inline]
  hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
  port_event drivers/usb/core/hub.c:5350 [inline]
  hub_event+0x1ada/0x3590 drivers/usb/core/hub.c:5432
  process_one_work+0x905/0x1570 kernel/workqueue.c:2269
  worker_thread+0x96/0xe20 kernel/workqueue.c:2415
  kthread+0x30b/0x410 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..


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