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: 6440 Comm: syz.0.172 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:435 Code: 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 50 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 90 79 cd fa 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 5b f1 25 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc900033d7b00 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88802c853c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200067af4c R12: 0000000000000a06 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 000055557a785500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d31fff8 CR3: 0000000066fdb000 CR4: 00000000003506e0 Call Trace: dummy_pullup+0xc1/0x120 drivers/usb/gadget/udc/dummy_hcd.c:914 usb_gadget_disconnect_locked+0x120/0x440 drivers/usb/gadget/udc/core.c:780 gadget_unbind_driver+0xc2/0x3e0 drivers/usb/gadget/udc/core.c:1669 device_remove drivers/base/dd.c:627 [inline] __device_release_driver drivers/base/dd.c:1352 [inline] device_release_driver_internal+0x408/0x6f0 drivers/base/dd.c:1375 driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1438 bus_remove_driver+0x221/0x2f0 drivers/base/bus.c:792 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1735 raw_release+0xda/0x260 drivers/usb/gadget/legacy/raw_gadget.c:416 __fput+0x221/0x940 fs/file_table.c:418 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff3aaf9de99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc3a620f68 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ff3ab227da0 RCX: 00007ff3aaf9de99 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ff3ab227da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00000000003fb9b0 R11: 0000000000000246 R12: 000000000001ead2 R13: 00007ff3ab225fac R14: 000000000001df14 R15: 00007ffc3a621070 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:435 Code: 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 50 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 90 79 cd fa 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 5b f1 25 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc900033d7b00 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88802c853c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200067af4c R12: 0000000000000a06 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 000055557a785500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d31fff8 CR3: 0000000066fdb000 CR4: 00000000003506e0 ---------------- Code disassembly (best guess): 0: 0f 1f 00 nopl (%rax) 3: 55 push %rbp 4: 41 57 push %r15 6: 41 56 push %r14 8: 41 55 push %r13 a: 41 54 push %r12 c: 53 push %rbx d: 48 83 ec 50 sub $0x50,%rsp 11: 49 89 fe mov %rdi,%r14 14: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 1b: fc ff df 1e: e8 90 79 cd fa call 0xfacd79b3 23: 4c 89 f0 mov %r14,%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 f7 mov %r14,%rdi 33: e8 5b f1 25 fb call 0xfb25f193 38: 4d 8b 26 mov (%r14),%r12 3b: 4c 89 74 24 10 mov %r14,0x10(%rsp)