============================================ WARNING: possible recursive locking detected 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53 #0 Not tainted -------------------------------------------- syz.0.821/7796 is trying to acquire lock: ffffffff89b120e8 (chaoskey_list_lock){+.+.}-{3:3}, at: chaoskey_release+0x15d/0x2c0 drivers/usb/misc/chaoskey.c:322 but task is already holding lock: ffffffff89b120e8 (chaoskey_list_lock){+.+.}-{3:3} , at: chaoskey_release+0x7f/0x2c0 drivers/usb/misc/chaoskey.c:299 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(chaoskey_list_lock); lock(chaoskey_list_lock); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by syz.0.821/7796: #0: ffffffff89b120e8 (chaoskey_list_lock){+.+.}-{3:3} , at: chaoskey_release+0x7f/0x2c0 drivers/usb/misc/chaoskey.c:299 stack backtrace: CPU: 0 UID: 0 PID: 7796 Comm: syz.0.821 Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_deadlock_bug+0x2e3/0x410 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain kernel/locking/lockdep.c:3891 [inline] __lock_acquire+0x2185/0x3ce0 kernel/locking/lockdep.c:5202 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 chaoskey_release+0x15d/0x2c0 drivers/usb/misc/chaoskey.c:322 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xadd/0x2ce0 kernel/exit.c:939 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f89267ddbfb Code: Unable to access opcode bytes at 0x7f89267ddbd1. RSP: 002b:00007f8925454f60 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007f89267ddbfb RDX: 00007f8925455ff0 RSI: 0000000080085502 RDI: 0000000000000003 RBP: 00007f8926850296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8926995f80 R15: 00007ffd56717aa8