[alsa-devel] general protection fault in snd_usb_create_mixer

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    46178223 usb: gadget: add raw-gadget interface
git tree:       https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=176f9836e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=99c88c44660624e7
dashboard link: https://syzkaller.appspot.com/bug?extid=a36ab65c6653d7ccdd62
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1447d3bae00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17ef3a86e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+a36ab65c6653d7ccdd62 at syzkaller.appspotmail.com

usb 1-1: 208:241 : does not exist
usb 1-1: 208:242 : does not exist
usb 1-1: 208:243 : does not exist
usb 1-1: 208:244 : does not exist
usb 1-1: 208:245 : does not exist
usb 1-1: 208:246 : does not exist
usb 1-1: 208:247 : does not exist
usb 1-1: 208:248 : does not exist
usb 1-1: 208:249 : does not exist
usb 1-1: 208:250 : does not exist
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 1 PID: 22 Comm: kworker/1:1 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: usb_hub_wq hub_event
RIP: 0010:snd_usb_mixer_controls_badd sound/usb/mixer.c:2931 [inline]
RIP: 0010:snd_usb_create_mixer+0xbb9/0x1890 sound/usb/mixer.c:3441
Code: ee e8 9b 23 a6 fc 41 39 ee 74 a4 e8 a1 22 a6 fc 48 8b 7c 24 28 89 ee  
e8 25 59 b4 fe 48 8d 78 10 48 89 c3 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28  
84 c0 74 08 3c 03 0f 8e 2f 09 00 00 8b 6b 10 bf 01
RSP: 0018:ffff8881d932f0a0 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffffff834c5dac
RDX: 0000000000000000 RSI: ffffffff834c5e1b RDI: 0000000000000010
RBP: 0000000000000021 R08: ffff8881da24e000 R09: fffffbfff11aadb5
R10: fffffbfff11aadb4 R11: ffffffff88d56da7 R12: 00000000000000da
R13: dffffc0000000000 R14: 00000000000000d0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000043f100 CR3: 0000000006c21000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  usb_audio_probe+0xc76/0x2010 sound/usb/card.c:653
  usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
  really_probe+0x281/0x6d0 drivers/base/dd.c:548
  driver_probe_device+0x104/0x210 drivers/base/dd.c:721
  __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
  bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
  __device_attach+0x217/0x360 drivers/base/dd.c:894
  bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
  device_add+0xae6/0x16f0 drivers/base/core.c:2202
  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+0x281/0x6d0 drivers/base/dd.c:548
  driver_probe_device+0x104/0x210 drivers/base/dd.c:721
  __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
  bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
  __device_attach+0x217/0x360 drivers/base/dd.c:894
  bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
  device_add+0xae6/0x16f0 drivers/base/core.c:2202
  usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2537
  hub_port_connect drivers/usb/core/hub.c:5184 [inline]
  hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
  port_event drivers/usb/core/hub.c:5470 [inline]
  hub_event+0x1df8/0x3800 drivers/usb/core/hub.c:5552
  process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
  worker_thread+0x96/0xe20 kernel/workqueue.c:2415
  kthread+0x318/0x420 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace 1d30a29898ec11e8 ]---
RIP: 0010:snd_usb_mixer_controls_badd sound/usb/mixer.c:2931 [inline]
RIP: 0010:snd_usb_create_mixer+0xbb9/0x1890 sound/usb/mixer.c:3441
Code: ee e8 9b 23 a6 fc 41 39 ee 74 a4 e8 a1 22 a6 fc 48 8b 7c 24 28 89 ee  
e8 25 59 b4 fe 48 8d 78 10 48 89 c3 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28  
84 c0 74 08 3c 03 0f 8e 2f 09 00 00 8b 6b 10 bf 01
RSP: 0018:ffff8881d932f0a0 EFLAGS: 00010202
RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffffff834c5dac
RDX: 0000000000000000 RSI: ffffffff834c5e1b RDI: 0000000000000010
RBP: 0000000000000021 R08: ffff8881da24e000 R09: fffffbfff11aadb5
R10: fffffbfff11aadb4 R11: ffffffff88d56da7 R12: 00000000000000da
R13: dffffc0000000000 R14: 00000000000000d0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000043f100 CR3: 0000000006c21000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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