usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 3-1: Product: syz
usb 3-1: Manufacturer: syz
usb 3-1: SerialNumber: syz
usb 3-1: 1:1 : UAC_AS_GENERAL descriptor not found
usb 3-1: selec
usb 3-1: selecting invalid altsetting 0
usb 3-1: USB disconnect, device number 2
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 1 UID: 0 PID: 40 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del lib/klist.c:230 [inline]
RIP: 0010:klist_remove+0x152/0x300 lib/klist.c:249
Code: 4d 89 f5 49 c1 ed 03 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 31 a4 61 fc 4d 8b 26 49 83 e4 fe 49 8d 7c 24 20 48 89 f8 48 c1 e8 03 <42> 80 3c 38 00 74 05 e8 12 a4 61 fc 49 8b 44 24 20 48 89 44 24 10
RSP: 0018:ffffc9000029f480 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffff88810827a380 RCX: ffffffff88e60701
RDX: 0000000000000001 RSI: ffffffff881c7620 RDI: 0000000000000020
RBP: ffffc9000029f580 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000053e80 R12: 0000000000000000
R13: 1ffff11022ad21c9 R14: ffff888115690e48 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88826defe000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561887921520 CR3: 000000010c324000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 __device_release_driver drivers/base/dd.c:1357 [inline]
 device_release_driver_internal+0x7aa/0x8c0 drivers/base/dd.c:1372
 device_release_driver+0x19/0x30 drivers/base/dd.c:1395
 bus_remove_device+0x44a/0x490 drivers/base/bus.c:664
 device_del+0x575/0xce0 drivers/base/core.c:3965
 usb_disable_device+0x3ab/0x770 drivers/usb/core/message.c:1478
 usb_disconnect+0x32c/0x950 drivers/usb/core/hub.c:2350
 hub_port_connect drivers/usb/core/hub.c:5420 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
 port_event drivers/usb/core/hub.c:5884 [inline]
 hub_event+0x1ad9/0x4290 drivers/usb/core/hub.c:5966
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0x8ab/0x1120 kernel/workqueue.c:3479
 worker_thread+0x9a7/0xde0 kernel/workqueue.c:3560
 kthread+0x35d/0x450 kernel/kthread.c:436
 ret_from_fork+0x2ce/0x680 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:klist_put lib/klist.c:212 [inline]
RIP: 0010:klist_del lib/klist.c:230 [inline]
RIP: 0010:klist_remove+0x152/0x300 lib/klist.c:249
Code: 4d 89 f5 49 c1 ed 03 43 80 7c 3d 00 00 74 08 4c 89 f7 e8 31 a4 61 fc 4d 8b 26 49 83 e4 fe 49 8d 7c 24 20 48 89 f8 48 c1 e8 03 <42> 80 3c 38 00 74 05 e8 12 a4 61 fc 49 8b 44 24 20 48 89 44 24 10
RSP: 0018:ffffc9000029f480 EFLAGS: 00010202
RAX: 0000000000000004 RBX: ffff88810827a380 RCX: ffffffff88e60701
RDX: 0000000000000001 RSI: ffffffff881c7620 RDI: 0000000000000020
RBP: ffffc9000029f580 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000053e80 R12: 0000000000000000
R13: 1ffff11022ad21c9 R14: ffff888115690e48 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88826defe000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561887921520 CR3: 000000010c324000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
   0:	4d 89 f5             	mov    %r14,%r13
   3:	49 c1 ed 03          	shr    $0x3,%r13
   7:	43 80 7c 3d 00 00    	cmpb   $0x0,0x0(%r13,%r15,1)
   d:	74 08                	je     0x17
   f:	4c 89 f7             	mov    %r14,%rdi
  12:	e8 31 a4 61 fc       	call   0xfc61a448
  17:	4d 8b 26             	mov    (%r14),%r12
  1a:	49 83 e4 fe          	and    $0xfffffffffffffffe,%r12
  1e:	49 8d 7c 24 20       	lea    0x20(%r12),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1) <-- trapping instruction
  2f:	74 05                	je     0x36
  31:	e8 12 a4 61 fc       	call   0xfc61a448
  36:	49 8b 44 24 20       	mov    0x20(%r12),%rax
  3b:	48 89 44 24 10       	mov    %rax,0x10(%rsp)