================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x2c57/0x3f20 kernel/locking/lockdep.c:3369 Read of size 8 at addr ffff888051bb69a0 by task syz-executor.0/11726 CPU: 0 PID: 11726 Comm: syz-executor.0 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 __lock_acquire+0x2c57/0x3f20 kernel/locking/lockdep.c:3369 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:176 spin_lock_bh include/linux/spinlock.h:322 [inline] lock_sock_nested+0x39/0x100 net/core/sock.c:2788 l2cap_sock_teardown_cb+0x93/0x650 net/bluetooth/l2cap_sock.c:1341 l2cap_chan_del+0xaf/0x950 net/bluetooth/l2cap_core.c:599 l2cap_conn_del+0x36e/0x690 net/bluetooth/l2cap_core.c:1729 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7441 [inline] l2cap_disconn_cfm+0x7c/0xb0 net/bluetooth/l2cap_core.c:7434 hci_disconn_cfm include/net/bluetooth/hci_core.h:1226 [inline] hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1393 hci_dev_do_close+0x535/0xca0 net/bluetooth/hci_core.c:1622 hci_unregister_dev+0x17f/0x8c0 net/bluetooth/hci_core.c:3193 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xa44/0x2850 kernel/exit.c:868 do_group_exit+0x100/0x2e0 kernel/exit.c:965 get_signal+0x38d/0x1ca0 kernel/signal.c:2423 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665f9 RSP: 002b:00007f8ef5d4a218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000056c160 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c160 RBP: 000000000056c158 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c164 R13: 00007ffce881e74f R14: 00007f8ef5d4a300 R15: 0000000000022000 Allocated by task 11232: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15a/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] sk_prot_alloc+0x1ba/0x290 net/core/sock.c:1467 sk_alloc+0x36/0xcd0 net/core/sock.c:1521 l2cap_sock_alloc.constprop.0+0x31/0x210 net/bluetooth/l2cap_sock.c:1618 l2cap_sock_create+0xf0/0x1a0 net/bluetooth/l2cap_sock.c:1664 bt_sock_create+0x13b/0x280 net/bluetooth/af_bluetooth.c:130 __sock_create+0x303/0x620 net/socket.c:1275 sock_create net/socket.c:1315 [inline] SYSC_socket net/socket.c:1345 [inline] SyS_socket+0xd1/0x1b0 net/socket.c:1325 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 11230: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 sk_prot_free net/core/sock.c:1504 [inline] __sk_destruct+0x5e3/0x760 net/core/sock.c:1582 sk_destruct net/core/sock.c:1597 [inline] __sk_free+0xd9/0x2d0 net/core/sock.c:1605 sk_free+0x2b/0x40 net/core/sock.c:1616 sock_put include/net/sock.h:1662 [inline] l2cap_sock_kill.part.0+0x106/0x130 net/bluetooth/l2cap_sock.c:1056 l2cap_sock_kill net/bluetooth/l2cap_sock.c:1047 [inline] l2cap_sock_release+0x1cd/0x280 net/bluetooth/l2cap_sock.c:1210 __sock_release+0xcd/0x2b0 net/socket.c:602 sock_close+0x15/0x20 net/socket.c:1139 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff888051bb6900 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 160 bytes inside of 2048-byte region [ffff888051bb6900, ffff888051bb7100) The buggy address belongs to the page: page:ffffea000146ed80 count:1 mapcount:0 mapping:ffff888051bb6080 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffff888051bb6080 0000000000000000 0000000100000003 raw: ffffea000146a5a0 ffffea0001451aa0 ffff88813fe80c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888051bb6880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888051bb6900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888051bb6980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888051bb6a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051bb6a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================