====================================================== WARNING: possible circular locking dependency detected 6.1.72-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor208/4275 is trying to acquire lock: ffff0000c46f4350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_request net/nfc/nci/core.c:148 [inline] ffff0000c46f4350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_set_local_general_bytes net/nfc/nci/core.c:774 [inline] ffff0000c46f4350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_start_poll+0x498/0x1204 net/nfc/nci/core.c:838 but task is already holding lock: ffff0000c46f2520 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1a8/0x308 net/nfc/netlink.c:826 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&genl_data->genl_data_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 nfc_urelease_event_work+0xfc/0x2a8 net/nfc/netlink.c:1849 process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292 worker_thread+0x8e4/0xfec kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864 -> #2 (nfc_devlist_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 nfc_register_device+0x4c/0x310 net/nfc/core.c:1116 nci_register_device+0x6ac/0x7c4 net/nfc/nci/core.c:1261 virtual_ncidev_open+0x6c/0xd8 drivers/nfc/virtual_ncidev.c:146 misc_open+0x2f0/0x368 drivers/char/misc.c:143 chrdev_open+0x3e8/0x4fc fs/char_dev.c:414 do_dentry_open+0x734/0xfa0 fs/open.c:882 vfs_open+0x7c/0x90 fs/open.c:1013 do_open fs/namei.c:3634 [inline] path_openat+0x1e14/0x2548 fs/namei.c:3791 do_filp_open+0x1bc/0x3cc fs/namei.c:3818 do_sys_openat2+0x128/0x3d8 fs/open.c:1318 do_sys_open fs/open.c:1334 [inline] __do_sys_openat fs/open.c:1350 [inline] __se_sys_openat fs/open.c:1345 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #1 (nci_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 virtual_nci_close+0x28/0x58 drivers/nfc/virtual_ncidev.c:44 nci_open_device net/nfc/nci/core.c:544 [inline] nci_dev_up+0x754/0xb10 net/nfc/nci/core.c:631 nfc_dev_up+0x154/0x300 net/nfc/core.c:118 nfc_genl_dev_up+0x98/0xdc net/nfc/netlink.c:770 genl_family_rcv_msg_doit net/netlink/genetlink.c:756 [inline] genl_family_rcv_msg net/netlink/genetlink.c:833 [inline] genl_rcv_msg+0x948/0xc2c net/netlink/genetlink.c:850 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2508 genl_rcv+0x38/0x50 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x65c/0x898 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x55c/0x848 net/socket.c:2514 ___sys_sendmsg net/socket.c:2568 [inline] __sys_sendmsg+0x26c/0x33c net/socket.c:2597 __do_sys_sendmsg net/socket.c:2606 [inline] __se_sys_sendmsg net/socket.c:2604 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2604 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #0 (&ndev->req_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 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+0x498/0x1204 net/nfc/nci/core.c:838 nfc_start_poll+0x164/0x2a4 net/nfc/core.c:225 nfc_genl_start_poll+0x1b8/0x308 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+0x948/0xc2c net/netlink/genetlink.c:850 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2508 genl_rcv+0x38/0x50 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x65c/0x898 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x55c/0x848 net/socket.c:2514 ___sys_sendmsg net/socket.c:2568 [inline] __sys_sendmsg+0x26c/0x33c net/socket.c:2597 __do_sys_sendmsg net/socket.c:2606 [inline] __se_sys_sendmsg net/socket.c:2604 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2604 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 other info that might help us debug this: Chain exists of: &ndev->req_lock --> nfc_devlist_mutex --> &genl_data->genl_data_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&genl_data->genl_data_mutex); lock(nfc_devlist_mutex); lock(&genl_data->genl_data_mutex); lock(&ndev->req_lock); *** DEADLOCK *** 4 locks held by syz-executor208/4275: #0: ffff800017e66330 (cb_lock){++++}-{3:3}, at: genl_rcv+0x28/0x50 net/netlink/genetlink.c:860 #1: ffff800017e661e8 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffff800017e661e8 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x114/0xc2c net/netlink/genetlink.c:848 #2: ffff0000c46f2520 (&genl_data->genl_data_mutex){+.+.}-{3:3}, at: nfc_genl_start_poll+0x1a8/0x308 net/nfc/netlink.c:826 #3: ffff0000c46f2100 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:836 [inline] #3: ffff0000c46f2100 (&dev->mutex){....}-{3:3}, at: nfc_start_poll+0x60/0x2a4 net/nfc/core.c:208 stack backtrace: CPU: 0 PID: 4275 Comm: syz-executor208 Not tainted 6.1.72-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2048 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 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+0x498/0x1204 net/nfc/nci/core.c:838 nfc_start_poll+0x164/0x2a4 net/nfc/core.c:225 nfc_genl_start_poll+0x1b8/0x308 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+0x948/0xc2c net/netlink/genetlink.c:850 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2508 genl_rcv+0x38/0x50 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x65c/0x898 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x55c/0x848 net/socket.c:2514 ___sys_sendmsg net/socket.c:2568 [inline] __sys_sendmsg+0x26c/0x33c net/socket.c:2597 __do_sys_sendmsg net/socket.c:2606 [inline] __se_sys_sendmsg net/socket.c:2604 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2604 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 nci: __nci_request: wait_for_completion_interruptible_timeout failed -512 nci: nci_start_poll: failed to set local general bytes nci: __nci_request: wait_for_completion_interruptible_timeout failed 0