ref_ctr going negative. vaddr: 0x20ffa002, curr val: -12288, delta: 1 ref_ctr increment failed for inode: 0x3e8f offset: 0x0 ref_ctr_offset: 0x2 of mm: 0x00000000d43e9cb1 ====================================================== WARNING: possible circular locking dependency detected 5.10.204 #1 Not tainted ------------------------------------------------------ syz-executor.5/9755 is trying to acquire lock: ffff8880182acae8 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}, at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050 but task is already holding lock: ffff8880182acf40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 -> #3 (&hdev->req_lock){+.+.}-{3:3}: __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 CPU: 0 PID: 9752 Comm: syz-executor.0 Not tainted 5.10.204 #1 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 Call Trace: rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 vfs_write+0x29a/0xa70 fs/read_write.c:603 fail_dump lib/fault-inject.c:52 [inline] should_fail.cold+0x5/0xa lib/fault-inject.c:146 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 should_failslab+0x5/0x20 mm/slab_common.c:1193 entry_SYSCALL_64_after_hwframe+0x62/0xc7 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 -> #2 kmem_cache_zalloc include/linux/slab.h:654 [inline] ext4_mb_new_blocks+0x64d/0x45b0 fs/ext4/mballoc.c:5117 ( rfkill_global_mutex ){+.+.}-{3:3} : __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 ext4_ext_map_blocks+0x1d68/0x5850 fs/ext4/extents.c:4281 rfkill_register+0x36/0xa10 net/rfkill/core.c:1016 hci_register_dev+0x42e/0xc00 net/bluetooth/hci_core.c:3773 __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 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 ){+.+.}-{3:3} : __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 ext4_map_blocks+0x652/0x1940 fs/ext4/inode.c:645 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 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 -> #0 ( ext4_alloc_file_blocks.isra.0+0x2eb/0xb40 fs/ext4/extents.c:4469 (work_completion)(&hdev->tx_work) ){+.+.}-{0:0} : ext4_fallocate+0x415/0x3860 fs/ext4/extents.c:4754 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 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 vfs_fallocate+0x48f/0xd00 fs/open.c:309 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 ksys_fallocate fs/open.c:332 [inline] __do_sys_fallocate fs/open.c:340 [inline] __se_sys_fallocate fs/open.c:338 [inline] __x64_sys_fallocate+0xcf/0x140 fs/open.c:338 entry_SYSCALL_64_after_hwframe+0x62/0xc7 other info that might help us debug this: do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 Chain exists of: entry_SYSCALL_64_after_hwframe+0x62/0xc7 (work_completion)(&hdev->tx_work) RIP: 0033:0x7f6d60f48b19 --> 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_global_mutex RSP: 002b:00007f6d5e4be188 EFLAGS: 00000246 --> ORIG_RAX: 000000000000011d &hdev->req_lock RAX: ffffffffffffffda RBX: 00007f6d6105bf60 RCX: 00007f6d60f48b19 Possible unsafe locking scenario: RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 CPU0 CPU1 ---- ---- RBP: 00007f6d5e4be1d0 R08: 0000000000000000 R09: 0000000000000000 lock(&hdev->req_lock R10: 0000000008800000 R11: 0000000000000246 R12: 0000000000000002 ); R13: 00007ffdd1e974af R14: 00007f6d5e4be300 R15: 0000000000022000 lock(rfkill_global_mutex); lock(&hdev->req_lock); lock((work_completion)(&hdev->tx_work)); *** DEADLOCK *** 2 locks held by syz-executor.5/9755: #0: ffffffff85619628 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 #1: ffff8880182acf40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 stack backtrace: CPU: 1 PID: 9755 Comm: syz-executor.5 Not tainted 5.10.204 #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 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: 0033:0x7ff8a1fd3b19 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:00007ff89f549188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ff8a20e6f60 RCX: 00007ff8a1fd3b19 RDX: 0000000000000008 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00007ff8a202df6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdfe57838f R14: 00007ff89f549300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 9771 Comm: syz-executor.0 Not tainted 5.10.204 #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 should_failslab+0x5/0x20 mm/slab_common.c:1193 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 mem_pool_alloc mm/kmemleak.c:423 [inline] create_object.isra.0+0x3a/0xa20 mm/kmemleak.c:578 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] __kmalloc+0x16e/0x390 mm/slub.c:3967 kmalloc_array include/linux/slab.h:592 [inline] kcalloc include/linux/slab.h:603 [inline] ext4_find_extent+0xa3d/0xd30 fs/ext4/extents.c:906 ext4_ext_map_blocks+0x1c8/0x5850 fs/ext4/extents.c:4097 ext4_map_blocks+0x652/0x1940 fs/ext4/inode.c:645 ext4_alloc_file_blocks.isra.0+0x2eb/0xb40 fs/ext4/extents.c:4469 ext4_fallocate+0x415/0x3860 fs/ext4/extents.c:4754 vfs_fallocate+0x48f/0xd00 fs/open.c:309 ksys_fallocate fs/open.c:332 [inline] __do_sys_fallocate fs/open.c:340 [inline] __se_sys_fallocate fs/open.c:338 [inline] __x64_sys_fallocate+0xcf/0x140 fs/open.c:338 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x62/0xc7 RIP: 0033:0x7f6d60f48b19 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:00007f6d5e4be188 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007f6d6105bf60 RCX: 00007f6d60f48b19 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f6d5e4be1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008800000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffdd1e974af R14: 00007f6d5e4be300 R15: 0000000000022000 ref_ctr going negative. vaddr: 0x20ffa002, curr val: -12288, delta: 1 ref_ctr increment failed for inode: 0x3e8f offset: 0x0 ref_ctr_offset: 0x2 of mm: 0x00000000d43e9cb1 ---------------- 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