list_add double add: new=ffff88803427a418, prev=ffff88803427a418, next=ffff888011092078. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:37! Oops: invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 7525 Comm: syz.1.582 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:__list_add_valid_or_report+0xa5/0x130 lib/list_debug.c:35 Code: 74 12 b0 01 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 c7 60 79 a6 8b 4c 89 fe 4c 89 f2 48 89 d9 e8 ec ec 7e fc 90 <0f> 0b 48 c7 c7 40 77 a6 8b e8 dd ec 7e fc 90 0f 0b 48 c7 c7 00 78 RSP: 0018:ffffc90003dcf310 EFLAGS: 00010246 RAX: 0000000000000058 RBX: ffff888011092078 RCX: d3093efb27a85800 RDX: ffffc9000e291000 RSI: 0000000000021419 RDI: 000000000002141a RBP: 1ffff11002212410 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff520007b9e11 R12: 1ffff1100684f483 R13: dffffc0000000000 R14: ffff88803427a418 R15: ffff88803427a418 FS: 00007f94626ce6c0(0000) GS:ffff888126336000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556d9aa28 CR3: 000000005c006000 CR4: 00000000003526f0 Call Trace: __list_add_valid include/linux/list.h:96 [inline] __list_add include/linux/list.h:158 [inline] list_add_tail include/linux/list.h:191 [inline] usb_hcd_link_urb_to_ep+0x1d2/0x330 drivers/usb/core/hcd.c:1154 dummy_urb_enqueue+0x290/0x760 drivers/usb/gadget/udc/dummy_hcd.c:1288 usb_hcd_submit_urb+0x323/0x1b50 drivers/usb/core/hcd.c:1542 cm109_submit_buzz_toggle drivers/input/misc/cm109.c:351 [inline] cm109_toggle_buzzer_async drivers/input/misc/cm109.c:484 [inline] cm109_input_ev+0x1e4/0x400 drivers/input/misc/cm109.c:615 input_event_dispose+0x80/0x6b0 drivers/input/input.c:322 input_inject_event+0x1d8/0x330 drivers/input/input.c:424 kd_sound_helper+0x101/0x210 drivers/tty/vt/keyboard.c:256 input_handler_for_each_handle+0x101/0x1c0 drivers/input/input.c:2520 kd_mksound+0x96/0x130 drivers/tty/vt/keyboard.c:280 handle_ascii drivers/tty/vt/vt.c:2329 [inline] do_con_trol drivers/tty/vt/vt.c:2646 [inline] do_con_write+0x335b/0x5360 drivers/tty/vt/vt.c:3230 con_write+0x31/0x2e0 drivers/tty/vt/vt.c:3566 process_output_block drivers/tty/n_tty.c:557 [inline] n_tty_write+0xd8a/0x12b0 drivers/tty/n_tty.c:2366 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write+0x562/0xa30 drivers/tty/tty_io.c:1081 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x629/0xba0 fs/read_write.c:688 ksys_write+0x156/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f946447c819 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:00007f94626ce028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f94646f5fa0 RCX: 00007f946447c819 RDX: 0000000000001006 RSI: 0000200000002140 RDI: 0000000000000005 RBP: 00007f9464512c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f94646f6038 R14: 00007f94646f5fa0 R15: 00007fff3b140978 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__list_add_valid_or_report+0xa5/0x130 lib/list_debug.c:35 Code: 74 12 b0 01 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 c7 60 79 a6 8b 4c 89 fe 4c 89 f2 48 89 d9 e8 ec ec 7e fc 90 <0f> 0b 48 c7 c7 40 77 a6 8b e8 dd ec 7e fc 90 0f 0b 48 c7 c7 00 78 RSP: 0018:ffffc90003dcf310 EFLAGS: 00010246 RAX: 0000000000000058 RBX: ffff888011092078 RCX: d3093efb27a85800 RDX: ffffc9000e291000 RSI: 0000000000021419 RDI: 000000000002141a RBP: 1ffff11002212410 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff520007b9e11 R12: 1ffff1100684f483 R13: dffffc0000000000 R14: ffff88803427a418 R15: ffff88803427a418 FS: 00007f94626ce6c0(0000) GS:ffff888126336000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556d9aa28 CR3: 000000005c006000 CR4: 00000000003526f0