hid-u2fzero 0003:10C4:8ACF.0028: unknown main item tag 0x0 hid-u2fzero 0003:10C4:8ACF.0028: unknown main item tag 0x0 hid-u2fzero 0003:10C4:8ACF.0028: hidraw0: USB HID vff.7f Device [HID 10c4:8acf] on usb-dummy_hcd.2-1/input0 hid-u2fzero 0003:10C4:8ACF.0028: 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: 4350 Comm: kworker/0:5 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:u2fzero_recv drivers/hid/hid-u2fzero.c:137 [inline] RIP: 0010:u2fzero_rng_read+0x281/0x700 drivers/hid/hid-u2fzero.c:223 Code: 49 c1 ee 03 41 80 3c 1e 00 74 08 4c 89 ff e8 a6 24 0e fa 4c 89 f8 41 bf a8 00 00 00 48 89 04 24 4c 03 38 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 01 25 0e fa 48 8d 44 24 60 49 89 07 RSP: 0018:ffffc900041168c0 EFLAGS: 00010202 RAX: 0000000000000015 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 000000000000003b RSI: 0000000000000000 RDI: ffff88805379bd69 RBP: ffffc90004116a60 R08: 0000000000000000 R09: ffff88805379bd2e R10: dffffc0000000000 R11: ffffed100a6f37ad R12: ffff88805808a3e0 R13: 1ffff92000822d20 R14: 1ffff1100b011406 R15: 00000000000000a8 FS: 0000000000000000(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe640ca6e80 CR3: 000000007c981000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rng_get_data drivers/char/hw_random/core.c:201 [inline] add_early_randomness+0x7a/0x150 drivers/char/hw_random/core.c:73 hwrng_register+0x398/0x440 drivers/char/hw_random/core.c:593 devm_hwrng_register+0x43/0xb0 drivers/char/hw_random/core.c:665 u2fzero_probe+0x35e/0x470 drivers/hid/hid-u2fzero.c:359 __hid_device_probe drivers/hid/hid-core.c:2678 [inline] hid_device_probe+0x2b8/0x520 drivers/hid/hid-core.c:2717 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x24a/0xb40 drivers/base/dd.c:638 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:804 driver_probe_device+0x4f/0x420 drivers/base/dd.c:834 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:962 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a7/0x480 drivers/base/dd.c:1034 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489 device_add+0xbcf/0x1050 drivers/base/core.c:3712 hid_add_device+0x361/0x500 drivers/hid/hid-core.c:2863 usbhid_probe+0xc3f/0x1010 drivers/hid/usbhid/hid-core.c:1442 usb_probe_interface+0x6e7/0xcf0 drivers/usb/core/driver.c:395 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x24a/0xb40 drivers/base/dd.c:638 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:804 driver_probe_device+0x4f/0x420 drivers/base/dd.c:834 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:962 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a7/0x480 drivers/base/dd.c:1034 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489 device_add+0xbcf/0x1050 drivers/base/core.c:3712 usb_set_configuration+0x19d5/0x2030 drivers/usb/core/message.c:2223 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x126/0x250 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x24a/0xb40 drivers/base/dd.c:638 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:804 driver_probe_device+0x4f/0x420 drivers/base/dd.c:834 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:962 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a7/0x480 drivers/base/dd.c:1034 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489 device_add+0xbcf/0x1050 drivers/base/core.c:3712 usb_new_device+0xa01/0x15e0 drivers/usb/core/hub.c:2664 hub_port_connect drivers/usb/core/hub.c:5522 [inline] hub_port_connect_change drivers/usb/core/hub.c:5662 [inline] port_event drivers/usb/core/hub.c:5822 [inline] hub_event+0x2b2f/0x5200 drivers/usb/core/hub.c:5904 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:u2fzero_recv drivers/hid/hid-u2fzero.c:137 [inline] RIP: 0010:u2fzero_rng_read+0x281/0x700 drivers/hid/hid-u2fzero.c:223 Code: 49 c1 ee 03 41 80 3c 1e 00 74 08 4c 89 ff e8 a6 24 0e fa 4c 89 f8 41 bf a8 00 00 00 48 89 04 24 4c 03 38 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 01 25 0e fa 48 8d 44 24 60 49 89 07 RSP: 0018:ffffc900041168c0 EFLAGS: 00010202 RAX: 0000000000000015 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 000000000000003b RSI: 0000000000000000 RDI: ffff88805379bd69 RBP: ffffc90004116a60 R08: 0000000000000000 R09: ffff88805379bd2e R10: dffffc0000000000 R11: ffffed100a6f37ad R12: ffff88805808a3e0 R13: 1ffff92000822d20 R14: 1ffff1100b011406 R15: 00000000000000a8 FS: 0000000000000000(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005623d2254000 CR3: 000000000d88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 49 c1 ee 03 shr $0x3,%r14 4: 41 80 3c 1e 00 cmpb $0x0,(%r14,%rbx,1) 9: 74 08 je 0x13 b: 4c 89 ff mov %r15,%rdi e: e8 a6 24 0e fa call 0xfa0e24b9 13: 4c 89 f8 mov %r15,%rax 16: 41 bf a8 00 00 00 mov $0xa8,%r15d 1c: 48 89 04 24 mov %rax,(%rsp) 20: 4c 03 38 add (%rax),%r15 23: 4c 89 f8 mov %r15,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 ff mov %r15,%rdi 33: e8 01 25 0e fa call 0xfa0e2539 38: 48 8d 44 24 60 lea 0x60(%rsp),%rax 3d: 49 89 07 mov %rax,(%r15)