kobject_add_internal failed for hci0:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci0: failed to register connection device ================================================================== BUG: KASAN: use-after-free in l2cap_sock_new_connection_cb+0x1ef/0x2a0 net/bluetooth/l2cap_sock.c:1517 Read of size 8 at addr ffff888027f13540 by task kworker/u5:8/4266 CPU: 1 PID: 4266 Comm: kworker/u5:8 Not tainted 6.1.116-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci0 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 l2cap_sock_new_connection_cb+0x1ef/0x2a0 net/bluetooth/l2cap_sock.c:1517 l2cap_connect_cfm+0x36b/0x1270 net/bluetooth/l2cap_core.c:8326 hci_connect_cfm+0x9e/0x150 include/net/bluetooth/hci_core.h:1788 le_conn_complete_evt+0xd54/0x1320 net/bluetooth/hci_event.c:6008 hci_le_conn_complete_evt+0x188/0x410 net/bluetooth/hci_event.c:6034 hci_event_func net/bluetooth/hci_event.c:7533 [inline] hci_event_packet+0xa40/0x1510 net/bluetooth/hci_event.c:7588 hci_rx_work+0x3cd/0xce0 net/bluetooth/hci_core.c:4100 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 4266: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc+0xb2/0x230 mm/slab_common.c:949 kmalloc include/linux/slab.h:562 [inline] sk_prot_alloc+0xe0/0x200 net/core/sock.c:2047 sk_alloc+0x36/0x350 net/core/sock.c:2100 bt_sock_alloc+0x37/0x130 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1911 [inline] l2cap_sock_new_connection_cb+0xd8/0x2a0 net/bluetooth/l2cap_sock.c:1502 l2cap_connect_cfm+0x36b/0x1270 net/bluetooth/l2cap_core.c:8326 hci_connect_cfm+0x9e/0x150 include/net/bluetooth/hci_core.h:1788 le_conn_complete_evt+0xd54/0x1320 net/bluetooth/hci_event.c:6008 hci_le_conn_complete_evt+0x188/0x410 net/bluetooth/hci_event.c:6034 hci_event_func net/bluetooth/hci_event.c:7533 [inline] hci_event_packet+0xa40/0x1510 net/bluetooth/hci_event.c:7588 hci_rx_work+0x3cd/0xce0 net/bluetooth/hci_core.c:4100 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Freed by task 4771: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674 sk_prot_free net/core/sock.c:2083 [inline] __sk_destruct+0x473/0x5f0 net/core/sock.c:2169 l2cap_sock_cleanup_listen+0xd9/0x270 net/bluetooth/l2cap_sock.c:1482 l2cap_sock_release+0x59/0x1d0 net/bluetooth/l2cap_sock.c:1445 __sock_release net/socket.c:654 [inline] sock_close+0xcd/0x230 net/socket.c:1400 __fput+0x3f6/0x8d0 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:203 get_signal+0x15fc/0x17d0 kernel/signal.c:2647 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845 netlink_release+0x1554/0x19e0 net/netlink/af_netlink.c:815 __sock_release net/socket.c:654 [inline] sock_close+0xcd/0x230 net/socket.c:1400 __fput+0x3f6/0x8d0 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888027f13000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1344 bytes inside of 2048-byte region [ffff888027f13000, ffff888027f13800) The buggy address belongs to the physical page: page:ffffea00009fc400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27f10 head:ffffea00009fc400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017c42000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4249, tgid 4249 (syz-executor), ts 79468130346, free_ts 79456645603 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517 prep_new_page mm/page_alloc.c:2524 [inline] get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5589 alloc_slab_page+0x6a/0x150 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x84/0x2d0 mm/slub.c:1992 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa1/0x230 mm/slab_common.c:949 kmalloc include/linux/slab.h:562 [inline] sk_prot_alloc+0xe0/0x200 net/core/sock.c:2047 sk_alloc+0x36/0x350 net/core/sock.c:2100 __netlink_create+0x6b/0x2c0 net/netlink/af_netlink.c:647 netlink_create+0x3aa/0x540 net/netlink/af_netlink.c:710 __sock_create+0x488/0x930 net/socket.c:1550 sock_create net/socket.c:1606 [inline] __sys_socket_create net/socket.c:1643 [inline] __sys_socket+0x136/0x3a0 net/socket.c:1671 __do_sys_socket net/socket.c:1684 [inline] __se_sys_socket net/socket.c:1682 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1682 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1444 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 getname_flags+0xb8/0x4f0 fs/namei.c:139 user_path_at_empty+0x28/0x60 fs/namei.c:2904 user_path_at include/linux/namei.h:57 [inline] __do_sys_chdir fs/open.c:514 [inline] __se_sys_chdir+0xbb/0x220 fs/open.c:508 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888027f13400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027f13480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888027f13500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888027f13580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027f13600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================