====================================================== WARNING: possible circular locking dependency detected 6.1.15-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/4187 is trying to acquire lock: ffffffff8d7c4128 (nci_mutex){+.+.}-{3:3}, at: virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44 but task is already holding lock: ffff8880587b9350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_close_device+0x106/0x5f0 net/nfc/nci/core.c:560 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ndev->req_lock){+.+.}-{3:3}: lock_acquire+0x231/0x620 kernel/locking/lockdep.c:5668 __mutex_lock_common+0x1d4/0x2520 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 nci_request net/nfc/nci/core.c:148 [inline] nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline] nci_start_poll+0x59f/0xf20 net/nfc/nci/core.c:838 nfc_start_poll+0x184/0x2f0 net/nfc/core.c:225 nfc_genl_start_poll+0x1e7/0x350 net/nfc/netlink.c:828 genl_family_rcv_msg_doit net/netlink/genetlink.c:756 [inline] genl_family_rcv_msg net/netlink/genetlink.c:833 [inline] genl_rcv_msg+0xc1a/0xf70 net/netlink/genetlink.c:850 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2550 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline] netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354 netlink_sendmsg+0x9fe/0xd10 net/netlink/af_netlink.c:1931 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2485 ___sys_sendmsg net/socket.c:2539 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&genl_data->genl_data_mutex){+.+.}-{3:3}: lock_acquire+0x231/0x620 kernel/locking/lockdep.c:5668 __mutex_lock_common+0x1d4/0x2520 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 nfc_urelease_event_work+0x113/0x2f0 net/nfc/netlink.c:1835 process_one_work+0x8ee/0x1350 kernel/workqueue.c:2289 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436 kthread+0x268/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 -> #1 (nfc_devlist_mutex){+.+.}-{3:3}: lock_acquire+0x231/0x620 kernel/locking/lockdep.c:5668 __mutex_lock_common+0x1d4/0x2520 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 nfc_register_device+0x38/0x310 net/nfc/core.c:1116 nci_register_device+0x7be/0x900 net/nfc/nci/core.c:1256 virtual_ncidev_open+0x55/0xc0 drivers/nfc/virtual_ncidev.c:146 misc_open+0x304/0x380 drivers/char/misc.c:143 chrdev_open+0x54a/0x630 fs/char_dev.c:414 do_dentry_open+0x7f9/0x10f0 fs/open.c:882 do_open fs/namei.c:3557 [inline] path_openat+0x263f/0x2e60 fs/namei.c:3714 do_filp_open+0x230/0x480 fs/namei.c:3741 do_sys_openat2+0x13b/0x500 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (nci_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3831 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5055 lock_acquire+0x231/0x620 kernel/locking/lockdep.c:5668 __mutex_lock_common+0x1d4/0x2520 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44 nci_close_device+0x3a8/0x5f0 net/nfc/nci/core.c:592 nci_unregister_device+0x3c/0x230 net/nfc/nci/core.c:1291 virtual_ncidev_close+0x55/0x90 drivers/nfc/virtual_ncidev.c:166 __fput+0x3b7/0x890 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:179 get_signal+0x15fc/0x17d0 kernel/signal.c:2635 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x60/0x2c0 kernel/entry/common.c:296 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: nci_mutex --> &genl_data->genl_data_mutex --> &ndev->req_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ndev->req_lock); lock(&genl_data->genl_data_mutex); lock(&ndev->req_lock); lock(nci_mutex); *** DEADLOCK *** 1 lock held by syz-executor.4/4187: #0: ffff8880587b9350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_close_device+0x106/0x5f0 net/nfc/nci/core.c:560 stack backtrace: CPU: 1 PID: 4187 Comm: syz-executor.4 Not tainted 6.1.15-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3831 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5055 lock_acquire+0x231/0x620 kernel/locking/lockdep.c:5668 __mutex_lock_common+0x1d4/0x2520 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44 nci_close_device+0x3a8/0x5f0 net/nfc/nci/core.c:592 nci_unregister_device+0x3c/0x230 net/nfc/nci/core.c:1291 virtual_ncidev_close+0x55/0x90 drivers/nfc/virtual_ncidev.c:166 __fput+0x3b7/0x890 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:179 get_signal+0x15fc/0x17d0 kernel/signal.c:2635 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x60/0x2c0 kernel/entry/common.c:296 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fed02a8c0f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fed0370d168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffff2 RBX: 00007fed02babf80 RCX: 00007fed02a8c0f9 RDX: 0000000000000064 RSI: 0000000020000840 RDI: 0000000000000003 RBP: 00007fed02ae7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff58fd3d0f R14: 00007fed0370d300 R15: 0000000000022000