dummy_hcd dummy_hcd.0: stopped dummy_hcd dummy_hcd.0: USB bus 1 deregistered general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 5377 Comm: syz.0.445 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: ff ff 90 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 7c 02 fb 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 3b a9 53 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc90003607640 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88802f5b3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520006c0eb4 R12: 0000000000000a02 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f86c59556b8 CR3: 000000005ca69000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dummy_pullup+0xbd/0x120 drivers/usb/gadget/udc/dummy_hcd.c:914 usb_gadget_disconnect_locked+0x123/0x4d0 drivers/usb/gadget/udc/core.c:782 gadget_unbind_driver+0xbe/0x3d0 drivers/usb/gadget/udc/core.c:1696 device_remove drivers/base/dd.c:547 [inline] __device_release_driver drivers/base/dd.c:1279 [inline] device_release_driver_internal+0x47d/0x7c0 drivers/base/dd.c:1305 driver_detach+0x1ef/0x2d0 drivers/base/dd.c:1368 bus_remove_driver+0x11c/0x230 drivers/base/bus.c:679 usb_gadget_unregister_driver+0x4a/0x70 drivers/usb/gadget/udc/core.c:1762 raw_release+0xd6/0x260 drivers/usb/gadget/legacy/raw_gadget.c:416 __fput+0x20a/0x8b0 fs/file_table.c:320 task_work_run+0x1d0/0x260 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x9d5/0x2570 kernel/exit.c:881 do_group_exit+0x229/0x2e0 kernel/exit.c:1024 get_signal+0x1259/0x1340 kernel/signal.c:2872 arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f769c19de99 Code: Unable to access opcode bytes at 0x7f769c19de6f. RSP: 002b:00007f769d01e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 000000000000000b RBX: 00007f769c425fa0 RCX: 00007f769c19de99 RDX: 000000000000000b RSI: 0000200000000200 RDI: 0000000000000004 RBP: 00007f769c233eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f769c426038 R14: 00007f769c425fa0 R15: 00007fff3e16f8b8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:435 Code: ff ff 90 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 7c 02 fb 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 3b a9 53 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc90003607640 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88802f5b3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520006c0eb4 R12: 0000000000000a02 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f86c59556b8 CR3: 000000005ca69000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff 90 55 41 57 41 call *0x41574155(%rax) 6: 56 push %rsi 7: 41 55 push %r13 9: 41 54 push %r12 b: 53 push %rbx c: 48 83 ec 50 sub $0x50,%rsp 10: 49 89 fe mov %rdi,%r14 13: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 1a: fc ff df 1d: e8 90 7c 02 fb call 0xfb027cb2 22: 4c 89 f0 mov %r14,%rax 25: 48 c1 e8 03 shr $0x3,%rax * 29: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction 2d: 74 08 je 0x37 2f: 4c 89 f7 mov %r14,%rdi 32: e8 3b a9 53 fb call 0xfb53a972 37: 4d 8b 26 mov (%r14),%r12 3a: 4c 89 74 24 10 mov %r14,0x10(%rsp)