INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 1 PID: 10000 Comm: kworker/1:16 Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 assign_lock_key kernel/locking/lockdep.c:894 [inline] register_lock_class+0x157d/0x1630 kernel/locking/lockdep.c:1206 __lock_acquire+0xf9/0x5640 kernel/locking/lockdep.c:4305 lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:5005 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:359 [inline] lock_sock_nested+0x3b/0x110 net/core/sock.c:3034 l2cap_sock_teardown_cb+0x88/0x400 net/bluetooth/l2cap_sock.c:1520 l2cap_chan_del+0xad/0x1300 net/bluetooth/l2cap_core.c:618 l2cap_chan_close+0x118/0xb10 net/bluetooth/l2cap_core.c:823 l2cap_chan_timeout+0x173/0x450 net/bluetooth/l2cap_core.c:436 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 ================================================================== BUG: KASAN: use-after-free in l2cap_sock_teardown_cb+0x3d9/0x400 net/bluetooth/l2cap_sock.c:1522 Read of size 8 at addr ffff8880958394c8 by task kworker/1:16/10000 CPU: 1 PID: 10000 Comm: kworker/1:16 Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 l2cap_sock_teardown_cb+0x3d9/0x400 net/bluetooth/l2cap_sock.c:1522 l2cap_chan_del+0xad/0x1300 net/bluetooth/l2cap_core.c:618 l2cap_chan_close+0x118/0xb10 net/bluetooth/l2cap_core.c:823 l2cap_chan_timeout+0x173/0x450 net/bluetooth/l2cap_core.c:436 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 6874: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 kmalloc_node include/linux/slab.h:577 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:574 kvmalloc include/linux/mm.h:750 [inline] kvmalloc_array include/linux/mm.h:768 [inline] alloc_fdtable+0xcd/0x280 fs/file.c:118 dup_fd+0x726/0xc90 fs/file.c:323 copy_files kernel/fork.c:1460 [inline] copy_process+0x1d99/0x6920 kernel/fork.c:2057 _do_fork+0xe8/0xb10 kernel/fork.c:2428 __do_sys_clone+0xc8/0x110 kernel/fork.c:2545 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 15124: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kfree+0x103/0x2c0 mm/slab.c:3756 kvfree+0x42/0x50 mm/util.c:603 __free_fdtable fs/file.c:34 [inline] put_files_struct fs/file.c:433 [inline] put_files_struct+0x267/0x350 fs/file.c:426 exit_files+0x7e/0xa0 fs/file.c:458 do_exit+0xb43/0x29f0 kernel/exit.c:801 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x428/0x1f00 kernel/signal.c:2757 arch_do_signal+0x82/0x2520 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:136 [inline] exit_to_user_mode_prepare+0x15d/0x1c0 kernel/entry/common.c:167 syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:242 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:287 Last call_rcu(): kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2894 [inline] call_rcu+0x14f/0x7e0 kernel/rcu/tree.c:2968 netlink_release+0xd43/0x1cf0 net/netlink/af_netlink.c:802 __sock_release+0xcd/0x280 net/socket.c:596 sock_close+0x18/0x20 net/socket.c:1277 __fput+0x285/0x920 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:140 [inline] exit_to_user_mode_prepare+0x195/0x1c0 kernel/entry/common.c:167 syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:242 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888095839000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1224 bytes inside of 2048-byte region [ffff888095839000, ffff888095839800) The buggy address belongs to the page: page:00000000332b1d1c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x95839 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00028be608 ffffea00029e37c8 ffff8880aa040800 raw: 0000000000000000 ffff888095839000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888095839380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888095839400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888095839480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888095839500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888095839580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================