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: 4343 Comm: syz.0.27 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:432 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 60 88 42 fb 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 0b ab 87 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc90005467c58 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88807ab19dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000a8cf78 R12: 0000000000000a06 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000555582100500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32714ff8 CR3: 000000002b5a5000 CR4: 00000000003506f0 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:911 usb_gadget_disconnect+0xd0/0x3a0 drivers/usb/gadget/udc/core.c:763 usb_gadget_remove_driver+0x4a/0x350 drivers/usb/gadget/udc/core.c:1491 usb_gadget_unregister_driver+0x15d/0x4c0 drivers/usb/gadget/udc/core.c:1654 raw_release+0xd6/0x260 drivers/usb/gadget/legacy/raw_gadget.c:416 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f789b343019 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:00007ffee4bc3418 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ffee4bc3500 RCX: 00007f789b343019 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00000000000127d0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000001b31520000 R11: 0000000000000246 R12: 00007ffee4bc3540 R13: 00007f789b5cafac R14: 0000000000012ef4 R15: 00007f789b5cafa0 Modules linked in: ---[ end trace 14014c8d13f7616d ]--- RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:432 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 60 88 42 fb 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 0b ab 87 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc90005467c58 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88807ab19dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000a8cf78 R12: 0000000000000a06 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000555582100500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32714ff8 CR3: 000000002b5a5000 CR4: 00000000003506f0 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 60 88 42 fb call 0xfb428882 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 0b ab 87 fb call 0xfb87ab42 37: 4d 8b 26 mov (%r14),%r12 3a: 4c 89 74 24 10 mov %r14,0x10(%rsp)