dummy_hcd dummy_hcd.0: remove, state 4 usb usb1: USB disconnect, device number 1 dummy_hcd dummy_hcd.0: stopped dummy_hcd dummy_hcd.0: USB bus 1 deregistered Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 5854 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:dummy_udc_start+0xd0/0x1f0 drivers/usb/gadget/udc/dummy_hcd.c:1004 Code: 41 83 ff 03 74 18 41 83 ff 05 0f 85 93 00 00 00 e8 a5 09 8c fa eb 0c e8 9e 09 8c fa eb 05 e8 97 09 8c fa 4c 89 f0 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 f7 e8 61 60 f8 fa 4d 8b 36 4c 89 f7 e8 RSP: 0018:ffffc9000471f810 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88802a3a4090 RCX: ffff888033d91f40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888024f7d000 R08: ffff888033d91f40 R09: 0000000000000004 R10: 0000000000000100 R11: 0000000000000005 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003 FS: 000055556f17d500(0000) GS:ffff888125af2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3f3f1b7000 CR3: 0000000046364000 CR4: 00000000003526f0 Call Trace: usb_gadget_udc_start_locked drivers/usb/gadget/udc/core.c:1237 [inline] gadget_bind_driver+0x3a8/0x9e0 drivers/usb/gadget/udc/core.c:1667 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __driver_attach+0x339/0x600 drivers/base/dd.c:1292 bus_for_each_dev+0x23e/0x2c0 drivers/base/bus.c:383 bus_add_driver+0x348/0x670 drivers/base/bus.c:763 driver_register+0x23a/0x320 drivers/base/driver.c:174 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1752 raw_ioctl_run drivers/usb/gadget/legacy/raw_gadget.c:596 [inline] raw_ioctl+0x1503/0x40d0 drivers/usb/gadget/legacy/raw_gadget.c:1307 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3f3f1cdb2b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007ffe5fbb6120 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f3f3f1cdb2b RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000004 RBP: 00007ffe5fbb71f0 R08: 0000000000000001 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00002000000000c0 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:dummy_udc_start+0xd0/0x1f0 drivers/usb/gadget/udc/dummy_hcd.c:1004 Code: 41 83 ff 03 74 18 41 83 ff 05 0f 85 93 00 00 00 e8 a5 09 8c fa eb 0c e8 9e 09 8c fa eb 05 e8 97 09 8c fa 4c 89 f0 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 f7 e8 61 60 f8 fa 4d 8b 36 4c 89 f7 e8 RSP: 0018:ffffc9000471f810 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88802a3a4090 RCX: ffff888033d91f40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888024f7d000 R08: ffff888033d91f40 R09: 0000000000000004 R10: 0000000000000100 R11: 0000000000000005 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003 FS: 000055556f17d500(0000) GS:ffff888125af2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3f3f1b7000 CR3: 0000000046364000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 41 83 ff 03 cmp $0x3,%r15d 4: 74 18 je 0x1e 6: 41 83 ff 05 cmp $0x5,%r15d a: 0f 85 93 00 00 00 jne 0xa3 10: e8 a5 09 8c fa call 0xfa8c09ba 15: eb 0c jmp 0x23 17: e8 9e 09 8c fa call 0xfa8c09ba 1c: eb 05 jmp 0x23 1e: e8 97 09 8c fa call 0xfa8c09ba 23: 4c 89 f0 mov %r14,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 f7 mov %r14,%rdi 34: e8 61 60 f8 fa call 0xfaf8609a 39: 4d 8b 36 mov (%r14),%r14 3c: 4c 89 f7 mov %r14,%rdi 3f: e8 .byte 0xe8