kobject_add_internal failed for hci2:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci2: failed to register connection device ================================================================== BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xc4/0x130 net/bluetooth/l2cap_sock.c:1659 Read of size 8 at addr ffff0000dc6874c8 by task kworker/u5:3/4028 CPU: 1 PID: 4028 Comm: kworker/u5:3 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci2 hci_rx_work Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x174/0x1e4 mm/kasan/report.c:451 __asan_report_load8_noabort+0x44/0x50 mm/kasan/report_generic.c:309 l2cap_sock_ready_cb+0xc4/0x130 net/bluetooth/l2cap_sock.c:1659 l2cap_chan_ready net/bluetooth/l2cap_core.c:1385 [inline] l2cap_le_start+0x59c/0x19dc net/bluetooth/l2cap_core.c:1497 l2cap_conn_ready net/bluetooth/l2cap_core.c:1766 [inline] l2cap_connect_cfm+0x5a8/0xe5c net/bluetooth/l2cap_core.c:8298 hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline] le_conn_complete_evt+0xa30/0x1228 net/bluetooth/hci_event.c:5432 hci_le_conn_complete_evt net/bluetooth/hci_event.c:5457 [inline] hci_le_meta_evt+0x234/0x31c0 net/bluetooth/hci_event.c:6178 hci_event_packet+0xd34/0x12b4 net/bluetooth/hci_event.c:6527 hci_rx_work+0x1c0/0x7c4 net/bluetooth/hci_core.c:5155 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Allocated by task 5905: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xbc/0xfc mm/kasan/common.c:513 __kasan_kmalloc+0x10/0x1c mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] __kmalloc+0x29c/0x4c8 mm/slub.c:4407 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0xc4/0x1f0 net/core/sock.c:1863 sk_alloc+0x40/0x3e0 net/core/sock.c:1916 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1861 [inline] l2cap_sock_create+0x140/0x33c net/bluetooth/l2cap_sock.c:1907 bt_sock_create+0x14c/0x248 net/bluetooth/af_bluetooth.c:130 __sock_create+0x43c/0x8a0 net/socket.c:1486 sock_create net/socket.c:1542 [inline] __sys_socket+0x168/0x310 net/socket.c:1584 __do_sys_socket net/socket.c:1593 [inline] __se_sys_socket net/socket.c:1591 [inline] __arm64_sys_socket+0x7c/0x94 net/socket.c:1591 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 5905: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0x128/0x1ec mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0x178/0x410 mm/slub.c:4559 sk_prot_free net/core/sock.c:1899 [inline] __sk_destruct+0x418/0x600 net/core/sock.c:1985 sk_destruct net/core/sock.c:2000 [inline] __sk_free+0x37c/0x4e8 net/core/sock.c:2011 sk_free+0x68/0xdc net/core/sock.c:2022 sock_put include/net/sock.h:1923 [inline] l2cap_sock_kill+0x114/0x228 net/bluetooth/l2cap_sock.c:1258 l2cap_sock_release+0x138/0x1b4 net/bluetooth/l2cap_sock.c:1429 __sock_release net/socket.c:649 [inline] sock_close+0xb8/0x1fc net/socket.c:1336 __fput+0x1c4/0x800 fs/file_table.c:280 ____fput+0x20/0x30 fs/file_table.c:308 task_work_run+0x130/0x1e4 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x670/0x20bc kernel/exit.c:874 do_group_exit+0x110/0x268 kernel/exit.c:996 get_signal+0x634/0x1550 kernel/signal.c:2900 do_signal arch/arm64/kernel/signal.c:890 [inline] do_notify_resume+0x3d0/0x32b8 arch/arm64/kernel/signal.c:943 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xd4/0x11c mm/kasan/generic.c:348 kvfree_call_rcu+0xb8/0x684 kernel/rcu/tree.c:3596 drop_sysctl_table+0x274/0x3a0 fs/proc/proc_sysctl.c:1678 unregister_sysctl_table+0x94/0x130 fs/proc/proc_sysctl.c:1716 unregister_net_sysctl_table+0x20/0x30 net/sysctl_net.c:175 __devinet_sysctl_unregister net/ipv4/devinet.c:2626 [inline] devinet_sysctl_unregister net/ipv4/devinet.c:2654 [inline] inetdev_destroy net/ipv4/devinet.c:326 [inline] inetdev_event+0x534/0x1234 net/ipv4/devinet.c:1611 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2018 [inline] call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] unregister_netdevice_many+0xec4/0x189c net/core/dev.c:11102 default_device_exit_batch+0x4c0/0x520 net/core/dev.c:11635 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x5e0/0x9bc net/core/net_namespace.c:599 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 The buggy address belongs to the object at ffff0000dc687000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1224 bytes inside of 2048-byte region [ffff0000dc687000, ffff0000dc687800) The buggy address belongs to the page: page:00000000caabca20 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11c680 head:00000000caabca20 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 0000000000000000 0000000100000001 ffff0000c0002900 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000dc687380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000dc687400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000dc687480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000dc687500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000dc687580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================