do_loop_readv_writev fs/read_write.c:761 [inline] do_loop_readv_writev fs/read_write.c:748 [inline] do_iter_read+0x4fa/0x760 fs/read_write.c:803 vfs_readv+0xe5/0x160 fs/read_write.c:921 ====================================================== WARNING: possible circular locking dependency detected 5.10.245 #1 Not tainted ------------------------------------------------------ syz-executor.4/8663 is trying to acquire lock: ffff88800e50cb78 ( (work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0} , at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050 but task is already holding lock: do_readv+0x139/0x300 fs/read_write.c:958 ffffffff85620a68 ( rfkill_global_mutex){+.+.}-{3:3} , at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 ( entry_SYSCALL_64_after_hwframe+0x67/0xd1 rfkill_global_mutex){+.+.}-{3:3} RIP: 0033:0x7f8d670bbb19 : __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 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 bc ff ff ff f7 d8 64 89 01 48 rfkill_register+0x36/0xa10 net/rfkill/core.c:1016 hci_register_dev+0x42e/0xc00 net/bluetooth/hci_core.c:3774 RSP: 002b:00007f8d64631188 EFLAGS: 00000246 __vhci_create_device+0x2c8/0x5c0 drivers/bluetooth/hci_vhci.c:129 vhci_create_device drivers/bluetooth/hci_vhci.c:153 [inline] vhci_open_timeout+0x38/0x50 drivers/bluetooth/hci_vhci.c:310 ORIG_RAX: 0000000000000013 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 RAX: ffffffffffffffda RBX: 00007f8d671cef60 RCX: 00007f8d670bbb19 kthread+0x38f/0x470 kernel/kthread.c:328 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:298 RDX: 0000000000000001 RSI: 00000000200015c0 RDI: 0000000000000003 -> #3 ( RBP: 00007f8d646311d0 R08: 0000000000000000 R09: 0000000000000000 &data->open_mutex){+.+.}-{3:3} R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 : __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 R13: 00007ffef5aea2bf R14: 00007f8d64631300 R15: 0000000000022000 vhci_send_frame+0x63/0xa0 drivers/bluetooth/hci_vhci.c:71 hci_send_frame+0x1b9/0x320 net/bluetooth/hci_core.c:4065 hci_sched_acl_pkt net/bluetooth/hci_core.c:4590 [inline] hci_sched_acl net/bluetooth/hci_core.c:4675 [inline] hci_tx_work+0xfb4/0x15d0 net/bluetooth/hci_core.c:4741 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:328 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:298 -> #2 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}: __flush_work+0x105/0xa90 kernel/workqueue.c:3053 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 hci_unregister_dev+0x179/0x460 net/bluetooth/hci_core.c:3854 vhci_release+0x70/0xf0 drivers/bluetooth/hci_vhci.c:345 __fput+0x285/0x9f0 fs/file_table.c:281 task_work_run+0xe2/0x1a0 kernel/task_work.c:185 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xb77/0x2600 kernel/exit.c:869 do_group_exit+0x125/0x310 kernel/exit.c:983 __do_sys_exit_group kernel/exit.c:994 [inline] __se_sys_exit_group kernel/exit.c:992 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:992 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 -> #1 (&hdev->req_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 hci_req_sync net/bluetooth/hci_request.c:277 [inline] bg_scan_update+0x82/0x500 net/bluetooth/hci_request.c:2897 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:328 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:298 -> #0 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3729 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955 lock_acquire kernel/locking/lockdep.c:5566 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3440 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 vfs_write+0x29a/0xb10 fs/read_write.c:603 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 other info that might help us debug this: Chain exists of: (work_completion)(&hdev->bg_scan_update) --> &data->open_mutex --> rfkill_global_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rfkill_global_mutex); lock(&data->open_mutex); lock(rfkill_global_mutex); lock((work_completion)(&hdev->bg_scan_update)); *** DEADLOCK *** 1 lock held by syz-executor.4/8663: #0: ffffffff85620a68 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 stack backtrace: CPU: 0 PID: 8663 Comm: syz-executor.4 Not tainted 5.10.245 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 check_noncircular+0x263/0x2e0 kernel/locking/lockdep.c:2123 check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3729 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955 lock_acquire kernel/locking/lockdep.c:5566 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3440 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 vfs_write+0x29a/0xb10 fs/read_write.c:603 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x7fcc51283b19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcc4e7f9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fcc51396f60 RCX: 00007fcc51283b19 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007fcc512ddf6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc55a6aaef R14: 00007fcc4e7f9300 R15: 0000000000022000 netlink: 248 bytes leftover after parsing attributes in process `syz-executor.1'. ieee80211 €˜§°ÇÛ ”uòQÇC !: Selected rate control algorithm 'minstrel_ht' debugfs: Directory '€˜§°ÇÛ ”uòQÇC !' with parent 'ieee80211' already present! audit: type=1326 audit(1760780410.812:138): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8666 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 audit: type=1326 audit(1760780410.819:139): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8666 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=435 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 audit: type=1326 audit(1760780410.830:140): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8666 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 FAULT_INJECTION: forcing a failure. name fail_page_alloc, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 8675 Comm: syz-executor.2 Not tainted 5.10.245 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 fail_dump lib/fault-inject.c:52 [inline] should_fail.cold+0x5/0xa lib/fault-inject.c:146 prepare_alloc_pages mm/page_alloc.c:4963 [inline] __alloc_pages_nodemask+0x182/0x600 mm/page_alloc.c:5005 alloc_pages_vma+0xbb/0x410 mm/mempolicy.c:2229 alloc_zeroed_user_highpage_movable include/linux/highmem.h:277 [inline] do_anonymous_page mm/memory.c:3635 [inline] handle_pte_fault mm/memory.c:4495 [inline] __handle_mm_fault mm/memory.c:4632 [inline] handle_mm_fault+0x152f/0x3500 mm/memory.c:4730 do_user_addr_fault+0x56e/0xc60 arch/x86/mm/fault.c:1345 handle_page_fault arch/x86/mm/fault.c:1402 [inline] exc_page_fault+0xa2/0x1a0 arch/x86/mm/fault.c:1458 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:571 RIP: 0010:copy_user_generic_string+0x2c/0x40 arch/x86/lib/copy_user_64.S:169 Code: cb 83 fa 08 72 27 89 f9 83 e1 07 74 15 83 e9 08 f7 d9 29 ca 8a 06 88 07 48 ff c6 48 ff c7 ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 48 a5 89 d1 f3 a4 31 c0 0f 01 ca e9 33 4a 1d 02 0f 1f 00 0f 01 RSP: 0018:ffff88801e06fb50 EFLAGS: 00050246 RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000010 RDX: 0000000000000000 RSI: ffff888037afcf80 RDI: 000000002000a000 RBP: 0000000020009080 R08: 0000000000000000 R09: ffff888037afcfff R10: ffffed1006f5f9ff R11: 0000000000000001 R12: 000000002000a080 R13: ffff888037afc000 R14: 00007ffffffff000 R15: 0000000000000000 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] _copy_to_user lib/usercopy.c:40 [inline] _copy_to_user+0x13d/0x180 lib/usercopy.c:33 copy_to_user include/linux/uaccess.h:200 [inline] pagemap_read+0x333/0x590 fs/proc/task_mmu.c:1667 do_loop_readv_writev fs/read_write.c:761 [inline] do_loop_readv_writev fs/read_write.c:748 [inline] do_iter_read+0x4fa/0x760 fs/read_write.c:803 vfs_readv+0xe5/0x160 fs/read_write.c:921 do_readv+0x139/0x300 fs/read_write.c:958 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x7f8d670bbb19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8d64631188 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 00007f8d671cef60 RCX: 00007f8d670bbb19 RDX: 0000000000000001 RSI: 00000000200015c0 RDI: 0000000000000003 RBP: 00007f8d646311d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffef5aea2bf R14: 00007f8d64631300 R15: 0000000000022000 audit: type=1326 audit(1760780410.841:142): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8672 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 audit: type=1326 audit(1760780410.835:141): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8666 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=322 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 audit: type=1326 audit(1760780410.932:143): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8672 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=257 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 audit: type=1326 audit(1760780410.946:144): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8672 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 audit: type=1326 audit(1760780410.946:145): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8672 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 netlink: 248 bytes leftover after parsing attributes in process `syz-executor.1'. ieee80211 €˜§°ÇÛ ”uòQÇC !: Selected rate control algorithm 'minstrel_ht' audit: type=1326 audit(1760780410.948:146): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8672 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=257 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 sysfs: cannot create duplicate filename '/class/ieee80211/€˜§°ÇÛ ”uòQÇC !' CPU: 0 PID: 8662 Comm: syz-executor.1 Not tainted 5.10.245 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 sysfs_warn_dup.cold+0x1c/0x29 fs/sysfs/dir.c:30 sysfs_do_create_link_sd+0x122/0x140 fs/sysfs/symlink.c:51 sysfs_do_create_link fs/sysfs/symlink.c:80 [inline] sysfs_create_link+0x5f/0xc0 fs/sysfs/symlink.c:92 device_add_class_symlinks drivers/base/core.c:2751 [inline] device_add+0x703/0x1c50 drivers/base/core.c:2959 wiphy_register+0x1da6/0x2850 net/wireless/core.c:915 ieee80211_register_hw+0x23c5/0x38b0 net/mac80211/main.c:1295 mac80211_hwsim_new_radio+0x1d04/0x4290 drivers/net/wireless/mac80211_hwsim.c:3300 audit: type=1326 audit(1760780410.958:147): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=8672 comm="syz-executor.0" exe="/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7feb7b512b19 code=0x7ffc0000 hwsim_new_radio_nl+0x991/0x1080 drivers/net/wireless/mac80211_hwsim.c:3881 genl_family_rcv_msg_doit+0x22d/0x330 net/netlink/genetlink.c:739 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] genl_rcv_msg+0x36a/0x5a0 net/netlink/genetlink.c:800 netlink_rcv_skb+0x14b/0x430 net/netlink/af_netlink.c:2503 genl_rcv+0x24/0x40 net/netlink/genetlink.c:811 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x6ce/0xa00 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x90f/0xe00 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:651 [inline] __sock_sendmsg+0x154/0x190 net/socket.c:663 ____sys_sendmsg+0x70d/0x870 net/socket.c:2378 ___sys_sendmsg+0xf3/0x170 net/socket.c:2432 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2461 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x7f8ea386fb19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8ea0de5188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8ea3982f60 RCX: 00007f8ea386fb19 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000005 RBP: 00007f8ea38c9f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdc79a353f R14: 00007f8ea0de5300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff c3 inc %ebx 2: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 9: 00 00 00 c: 0f 1f 40 00 nopl 0x0(%rax) 10: 48 89 f8 mov %rdi,%rax 13: 48 89 f7 mov %rsi,%rdi 16: 48 89 d6 mov %rdx,%rsi 19: 48 89 ca mov %rcx,%rdx 1c: 4d 89 c2 mov %r8,%r10 1f: 4d 89 c8 mov %r9,%r8 22: 4c 8b 4c 24 08 mov 0x8(%rsp),%r9 27: 0f 05 syscall * 29: 48 3d 01 f0 ff ff cmp $0xfffffffffffff001,%rax <-- trapping instruction 2f: 73 01 jae 0x32 31: c3 retq 32: 48 c7 c1 bc ff ff ff mov $0xffffffffffffffbc,%rcx 39: f7 d8 neg %eax 3b: 64 89 01 mov %eax,%fs:(%rcx) 3e: 48 rex.W