syzbot


general protection fault in snd_scarlett2_controls_create

Status: upstream: reported C repro on 2026/04/10 02:21
Bug presence: origin:lts
[Documentation on labels]
Reported-by: syzbot+09c3f88d3038d4ed004b@syzkaller.appspotmail.com
First crash: 17d, last: 3d04h
Bug presence (2)
Date Name Commit Repro Result
2026/04/10 lts (merge base) f2ddafa93a25 C [report] general protection fault in snd_scarlett2_controls_create
2026/04/10 upstream (ToT) 9a9c8ce300cd C Didn't crash
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-12 general protection fault in snd_scarlett2_controls_create origin:upstream 2 C 9 2d22h 54d 0/1 premoderation: reported C repro on 2026/03/04 05:04
upstream general protection fault in snd_scarlett2_controls_create sound 2 C 5 54d 50d 28/29 upstream: reported C repro on 2026/03/07 23:59
Last patch testing requests (3)
Created Duration User Patch Repo Result
2026/04/24 10:40 12m retest repro android14-6.1 report log
2026/04/24 10:40 16m retest repro android14-6.1 report log
2026/04/24 10:40 13m retest repro android14-6.1 report log

Sample crash report:
usb 3-1: 1:1 : UAC_AS_GENERAL descriptor not found
usb 3-1: unit 5 not found!
usb 3-1: Focusrite Scarlett Gen 3 Mixer Driver enabled (pid=0x8214); report any issues to g@b4.vu
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 24 Comm: kworker/1:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:scarlett2_find_fc_interface sound/usb/mixer_scarlett2.c:3904 [inline]
RIP: 0010:scarlett2_init_private sound/usb/mixer_scarlett2.c:3938 [inline]
RIP: 0010:snd_scarlett2_controls_create+0x793/0x3ea0 sound/usb/mixer_scarlett2.c:4275
Code: 08 48 8d 9f 00 01 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 9b 31 00 00 44 88 33 49 8d 5f 02 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 9f 31 00 00 44 0f b6 33 41 80 e6 0f 48
RSP: 0018:ffffc90000196520 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000
RDX: ffff88810033e540 RSI: 00000000000000ff RDI: ffff888115925000
RBP: ffffc90000196880 R08: 0000000000000000 R09: ffff888115925058
R10: dffffc0000000000 R11: ffffed1022b24a0d R12: dffffc0000000000
R13: fffff52000032cb8 R14: 0000000000000002 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7661b85980 CR3: 000000010f373000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 snd_scarlett2_init+0x1d4/0x360 sound/usb/mixer_scarlett2.c:4395
 snd_usb_mixer_apply_create_quirk+0x190e/0x2b40 sound/usb/mixer_quirks.c:3724
 snd_usb_create_mixer+0x1a3a/0x2600 sound/usb/mixer.c:3637
 usb_audio_probe+0x1349/0x1da0 sound/usb/card.c:949
 usb_probe_interface+0x63f/0xb20 drivers/usb/core/driver.c:397
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2cb/0x960 drivers/base/dd.c:639
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:808
 driver_probe_device+0x54/0x3e0 drivers/base/dd.c:838
 __device_attach_driver+0x2e9/0x4a0 drivers/base/dd.c:966
 bus_for_each_drv+0x192/0x220 drivers/base/bus.c:429
 __device_attach+0x2b0/0x420 drivers/base/dd.c:1038
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:1087
 bus_probe_device+0xc0/0x1f0 drivers/base/bus.c:489
 device_add+0xb4d/0xef0 drivers/base/core.c:3698
 usb_set_configuration+0x19c2/0x1f10 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x91/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x159/0x270 drivers/usb/core/driver.c:294
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2cb/0x960 drivers/base/dd.c:639
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:808
 driver_probe_device+0x54/0x3e0 drivers/base/dd.c:838
 __device_attach_driver+0x2e9/0x4a0 drivers/base/dd.c:966
 bus_for_each_drv+0x192/0x220 drivers/base/bus.c:429
 __device_attach+0x2b0/0x420 drivers/base/dd.c:1038
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:1087
 bus_probe_device+0xc0/0x1f0 drivers/base/bus.c:489
 device_add+0xb4d/0xef0 drivers/base/core.c:3698
 usb_new_device+0xa81/0x1550 drivers/usb/core/hub.c:2684
 hub_port_connect drivers/usb/core/hub.c:5594 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5734 [inline]
 port_event drivers/usb/core/hub.c:5898 [inline]
 hub_event+0x2aca/0x46b0 drivers/usb/core/hub.c:5980
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302
 worker_thread+0xa29/0x11e0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:scarlett2_find_fc_interface sound/usb/mixer_scarlett2.c:3904 [inline]
RIP: 0010:scarlett2_init_private sound/usb/mixer_scarlett2.c:3938 [inline]
RIP: 0010:snd_scarlett2_controls_create+0x793/0x3ea0 sound/usb/mixer_scarlett2.c:4275
Code: 08 48 8d 9f 00 01 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 9b 31 00 00 44 88 33 49 8d 5f 02 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 9f 31 00 00 44 0f b6 33 41 80 e6 0f 48
RSP: 0018:ffffc90000196520 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000
RDX: ffff88810033e540 RSI: 00000000000000ff RDI: ffff888115925000
RBP: ffffc90000196880 R08: 0000000000000000 R09: ffff888115925058
R10: dffffc0000000000 R11: ffffed1022b24a0d R12: dffffc0000000000
R13: fffff52000032cb8 R14: 0000000000000002 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7661b85980 CR3: 00000001101db000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	08 48 8d             	or     %cl,-0x73(%rax)
   3:	9f                   	lahf
   4:	00 01                	add    %al,(%rcx)
   6:	00 00                	add    %al,(%rax)
   8:	48 89 d8             	mov    %rbx,%rax
   b:	48 c1 e8 03          	shr    $0x3,%rax
   f:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax
  14:	84 c0                	test   %al,%al
  16:	0f 85 9b 31 00 00    	jne    0x31b7
  1c:	44 88 33             	mov    %r14b,(%rbx)
  1f:	49 8d 5f 02          	lea    0x2(%r15),%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 9f 31 00 00    	jne    0x31d6
  37:	44 0f b6 33          	movzbl (%rbx),%r14d
  3b:	41 80 e6 0f          	and    $0xf,%r14b
  3f:	48                   	rex.W

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/10 03:07 android14-6.1 b1e92db6a41f 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in snd_scarlett2_controls_create
2026/04/10 02:40 android14-6.1 b1e92db6a41f 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in snd_scarlett2_controls_create
2026/04/10 02:14 android14-6.1 b1e92db6a41f 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in snd_scarlett2_controls_create
2026/04/10 01:49 android14-6.1 b1e92db6a41f 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in snd_scarlett2_controls_create
* Struck through repros no longer work on HEAD.