================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3671/0x4370 kernel/locking/lockdep.c:3828 Read of size 8 at addr ffff8881f2edf0a0 by task kworker/1:3/6253 CPU: 1 PID: 6253 Comm: kworker/1:3 Not tainted 5.4.0-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+0x128/0x182 lib/dump_stack.c:118 print_address_description.constprop.8.cold.10+0x9/0x317 mm/kasan/report.c:374 __kasan_report.cold.11+0x1c/0x37 mm/kasan/report.c:506 kasan_report+0xe/0x20 mm/kasan/common.c:634 __lock_acquire+0x3671/0x4370 kernel/locking/lockdep.c:3828 lock_acquire+0x19b/0x420 kernel/locking/lockdep.c:4487 __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:343 [inline] lock_sock_nested+0x35/0xf0 net/core/sock.c:2938 l2cap_sock_teardown_cb+0x7f/0x380 net/bluetooth/l2cap_sock.c:1331 l2cap_chan_del+0x9a/0x7e0 net/bluetooth/l2cap_core.c:603 l2cap_chan_close+0x34a/0x7d0 net/bluetooth/l2cap_core.c:761 l2cap_chan_timeout+0x115/0x1d0 net/bluetooth/l2cap_core.c:432 process_one_work+0x8d1/0x15c0 kernel/workqueue.c:2269 worker_thread+0x82/0xb50 kernel/workqueue.c:2415 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 9553: save_stack+0x19/0x80 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.13+0xc1/0xd0 mm/kasan/common.c:483 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x164/0x7b0 mm/slab.c:3664 kmalloc include/linux/slab.h:561 [inline] sk_prot_alloc+0x14d/0x260 net/core/sock.c:1605 sk_alloc+0x30/0xc80 net/core/sock.c:1659 __netlink_create+0x56/0x250 net/netlink/af_netlink.c:629 netlink_create+0x2f3/0x540 net/netlink/af_netlink.c:692 __sock_create+0x267/0x540 net/socket.c:1418 sock_create net/socket.c:1469 [inline] __sys_socket+0xd1/0x1a0 net/socket.c:1511 __do_sys_socket net/socket.c:1520 [inline] __se_sys_socket net/socket.c:1518 [inline] __x64_sys_socket+0x6a/0xb0 net/socket.c:1518 do_syscall_64+0xc6/0x5d0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9591: save_stack+0x19/0x80 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:471 __cache_free mm/slab.c:3425 [inline] kfree+0x107/0x2b0 mm/slab.c:3756 sk_prot_free net/core/sock.c:1642 [inline] __sk_destruct+0x451/0x600 net/core/sock.c:1726 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2157 [inline] rcu_core+0x52d/0x13f0 kernel/rcu/tree.c:2377 __do_softirq+0x26b/0x9a4 kernel/softirq.c:292 The buggy address belongs to the object at ffff8881f2edf000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 160 bytes inside of 2048-byte region [ffff8881f2edf000, ffff8881f2edf800) The buggy address belongs to the page: page:ffffea0007cbb7c0 refcount:1 mapcount:0 mapping:ffff8881f5400e00 index:0x0 raw: 017ffe0000000200 ffffea0007cb2908 ffffea00077e3348 ffff8881f5400e00 raw: 0000000000000000 ffff8881f2edf000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881f2edef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881f2edf000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881f2edf080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881f2edf100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881f2edf180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================