============================================ WARNING: possible recursive locking detected 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0 Not tainted -------------------------------------------- syz.1.16/6532 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.1.16/6532: #0: ffffffff89b120e8 (chaoskey_list_lock){+.+.}-{3:3}, at: chaoskey_release+0x7f/0x2c0 drivers/usb/misc/chaoskey.c:299 stack backtrace: CPU: 1 UID: 0 PID: 6532 Comm: syz.1.16 Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #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 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x24e/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: 0033:0x7f35b167dff9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe690a74c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000001c363 RCX: 00007f35b167dff9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f35b1837a80 R08: 0000000000000001 R09: 00007ffe690a77bf R10: 00007f35b14fa000 R11: 0000000000000246 R12: 000000000001cf4f R13: 00007ffe690a75d0 R14: 0000000000000bea R15: ffffffffffffffff