====================================================== FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 WARNING: possible circular locking dependency detected 5.10.199 #1 Not tainted CPU: 0 PID: 5484 Comm: syz-executor.2 Not tainted 5.10.199 #1 ------------------------------------------------------ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 syz-executor.7/5460 is trying to acquire lock: ffff888017d84ae8 Call Trace: ((work_completion)(&hdev->tx_work) __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 ){+.+.}-{0:0} fail_dump lib/fault-inject.c:52 [inline] should_fail.cold+0x5/0xa lib/fault-inject.c:146 , at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050 but task is already holding lock: ffff888017d84f40 ( should_failslab+0x5/0x20 mm/slab_common.c:1193 &hdev->req_lock){+.+.}-{3:3} slab_pre_alloc_hook mm/slab.h:515 [inline] slab_alloc_node mm/slub.c:2821 [inline] slab_alloc mm/slub.c:2904 [inline] kmem_cache_alloc+0x5b/0x310 mm/slub.c:2909 , at: hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 which lock already depends on the new lock. mem_pool_alloc mm/kmemleak.c:423 [inline] create_object.isra.0+0x3a/0xa20 mm/kmemleak.c:578 the existing dependency chain (in reverse order) is: -> #3 (&hdev->req_lock kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] slab_post_alloc_hook mm/slab.h:534 [inline] slab_alloc_node mm/slub.c:2896 [inline] slab_alloc mm/slub.c:2904 [inline] kmem_cache_alloc+0x159/0x310 mm/slub.c:2909 ){+.+.}-{3:3}: kmem_cache_zalloc include/linux/slab.h:654 [inline] lsm_inode_alloc security/security.c:592 [inline] security_inode_alloc+0x34/0x160 security/security.c:988 __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 inode_init_always+0xa4e/0xd10 fs/inode.c:204 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/0xa70 fs/read_write.c:603 alloc_inode+0x84/0x240 fs/inode.c:240 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 new_inode_pseudo fs/inode.c:929 [inline] new_inode+0x23/0x250 fs/inode.c:958 entry_SYSCALL_64_after_hwframe+0x62/0xc7 -> #2 shmem_get_inode+0x15e/0xbc0 mm/shmem.c:2294 (rfkill_global_mutex shmem_mknod+0x5a/0x1f0 mm/shmem.c:2931 ){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 rfkill_register+0x36/0xa10 net/rfkill/core.c:1016 vfs_create fs/namei.c:2872 [inline] vfs_create+0x3f7/0x640 fs/namei.c:2858 hci_register_dev+0x42e/0xc00 net/bluetooth/hci_core.c:3773 __vhci_create_device+0x2c8/0x5c0 drivers/bluetooth/hci_vhci.c:129 do_mknodat+0x438/0x4b0 fs/namei.c:3661 vhci_create_device drivers/bluetooth/hci_vhci.c:153 [inline] vhci_open_timeout+0x38/0x50 drivers/bluetooth/hci_vhci.c:310 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:313 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299 -> #1 (&data->open_mutex do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 ){+.+.}-{3:3}: entry_SYSCALL_64_after_hwframe+0x62/0xc7 __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 vhci_send_frame+0x63/0xa0 drivers/bluetooth/hci_vhci.c:71 RIP: 0033:0x7f1b55aa8b19 hci_send_frame+0x1b9/0x320 net/bluetooth/hci_core.c:4060 hci_sched_acl_pkt net/bluetooth/hci_core.c:4585 [inline] hci_sched_acl net/bluetooth/hci_core.c:4670 [inline] hci_tx_work+0x10af/0x1660 net/bluetooth/hci_core.c:4741 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 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 RSP: 002b:00007f1b5301e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000103 kthread+0x38f/0x470 kernel/kthread.c:313 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299 RAX: ffffffffffffffda RBX: 00007f1b55bbbf60 RCX: 00007f1b55aa8b19 -> #0 ( RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 (work_completion)(&hdev->tx_work)){+.+.}-{0:0} RBP: 00007f1b5301e1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000705 R11: 0000000000000246 R12: 0000000000000001 : check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3728 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4954 R13: 00007ffff2d6657f R14: 00007f1b5301e300 R15: 0000000000022000 lock_acquire kernel/locking/lockdep.c:5565 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5530 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 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/0xa70 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+0x62/0xc7 other info that might help us debug this: Chain exists of: (work_completion)(&hdev->tx_work) --> rfkill_global_mutex --> &hdev->req_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&hdev->req_lock); lock(rfkill_global_mutex); lock(&hdev->req_lock); lock((work_completion)(&hdev->tx_work)); *** DEADLOCK *** 2 locks held by syz-executor.7/5460: #0: ffffffff85619468 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 #1: ffff888017d84f40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 stack backtrace: CPU: 1 PID: 5460 Comm: syz-executor.7 Not tainted 5.10.199 #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:3728 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4954 lock_acquire kernel/locking/lockdep.c:5565 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5530 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 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/0xa70 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+0x62/0xc7 RIP: 0033:0x7fe97d677b19 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:00007fe97abed188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe97d78af60 RCX: 00007fe97d677b19 RDX: 0000000000000008 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00007fe97d6d1f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcee48d76f R14: 00007fe97abed300 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