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hid-u2fzero 0003:10C4:8ACF.0001: unknown main item tag 0x6
hid-u2fzero 0003:10C4:8ACF.0001: hidraw0: USB HID v0.00 Device [HID 10c4:8acf] on usb-dummy_hcd.0-1/input0
hid-u2fzero 0003:10C4:8ACF.0001: U2F Zero LED initialised
general protection fault, probably for non-canonical address 0xdffffc0000000015: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000a8-0x00000000000000af]
CPU: 0 PID: 5815 Comm: kworker/0:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:u2fzero_recv drivers/hid/hid-u2fzero.c:137 [inline]
RIP: 0010:u2fzero_rng_read+0x241/0x630 drivers/hid/hid-u2fzero.c:223
Code: 24 18 80 3c 01 00 74 08 4c 89 ef e8 d9 92 f8 f9 bb a8 00 00 00 49 03 5d 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 51 93 f8 f9 48 8d 44 24 60 48 89 03
RSP: 0018:ffffc900046ee780 EFLAGS: 00010202
RAX: 0000000000000015 RBX: 00000000000000a8 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffc900046ee8a0 RDI: ffff8880774cff68
RBP: ffffc900046ee998 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88807bcae300
R13: ffff88807bcae030 R14: 1ffff1100f795c83 R15: 1ffff920008ddcf8
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4db0fe20c0 CR3: 00000000302ea000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 rng_get_data drivers/char/hw_random/core.c:198 [inline]
 add_early_randomness+0x7a/0x1a0 drivers/char/hw_random/core.c:72
 hwrng_register+0x3db/0x4a0 drivers/char/hw_random/core.c:593
 devm_hwrng_register+0x47/0xb0 drivers/char/hw_random/core.c:665
 u2fzero_probe+0x348/0x460 drivers/hid/hid-u2fzero.c:358
 __hid_device_probe drivers/hid/hid-core.c:2649 [inline]
 hid_device_probe+0x293/0x5b0 drivers/hid/hid-core.c:2686
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 hid_add_device+0x38d/0x530 drivers/hid/hid-core.c:2832
 usbhid_probe+0xe02/0x1220 drivers/hid/usbhid/hid-core.c:1432
 usb_probe_interface+0x5a4/0xb00 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x13d/0x280 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 usb_new_device+0xa31/0x1630 drivers/usb/core/hub.c:2660
 hub_port_connect drivers/usb/core/hub.c:5529 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
 port_event drivers/usb/core/hub.c:5833 [inline]
 hub_event+0x2962/0x49c0 drivers/usb/core/hub.c:5915
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:u2fzero_recv drivers/hid/hid-u2fzero.c:137 [inline]
RIP: 0010:u2fzero_rng_read+0x241/0x630 drivers/hid/hid-u2fzero.c:223
Code: 24 18 80 3c 01 00 74 08 4c 89 ef e8 d9 92 f8 f9 bb a8 00 00 00 49 03 5d 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 51 93 f8 f9 48 8d 44 24 60 48 89 03
RSP: 0018:ffffc900046ee780 EFLAGS: 00010202
RAX: 0000000000000015 RBX: 00000000000000a8 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffc900046ee8a0 RDI: ffff8880774cff68
RBP: ffffc900046ee998 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88807bcae300
R13: ffff88807bcae030 R14: 1ffff1100f795c83 R15: 1ffff920008ddcf8
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4db0fb6ad8 CR3: 000000002e0a1000 CR4: 00000000003506f0
----------------
Code disassembly (best guess):
   0:	24 18                	and    $0x18,%al
   2:	80 3c 01 00          	cmpb   $0x0,(%rcx,%rax,1)
   6:	74 08                	je     0x10
   8:	4c 89 ef             	mov    %r13,%rdi
   b:	e8 d9 92 f8 f9       	call   0xf9f892e9
  10:	bb a8 00 00 00       	mov    $0xa8,%ebx
  15:	49 03 5d 00          	add    0x0(%r13),%rbx
  19:	48 89 d8             	mov    %rbx,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	48 89 df             	mov    %rbx,%rdi
  33:	e8 51 93 f8 f9       	call   0xf9f89389
  38:	48 8d 44 24 60       	lea    0x60(%rsp),%rax
  3d:	48 89 03             	mov    %rax,(%rbx)