kobject: kobject_add_internal failed for hci3:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci3: failed to register connection device ================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_new_connection_cb+0x1f8/0x2b0 net/bluetooth/l2cap_sock.c:1484 Read of size 8 at addr ffff88802d7f1580 by task kworker/u9:2/5837 CPU: 1 UID: 0 PID: 5837 Comm: kworker/u9:2 Not tainted 6.14.0-rc2-next-20250210-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: hci3 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 l2cap_sock_new_connection_cb+0x1f8/0x2b0 net/bluetooth/l2cap_sock.c:1484 l2cap_connect_cfm+0x336/0x1090 net/bluetooth/l2cap_core.c:7223 hci_connect_cfm+0x162/0x240 include/net/bluetooth/hci_core.h:2051 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5763 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5789 hci_event_func net/bluetooth/hci_event.c:7470 [inline] hci_event_packet+0xa55/0x1540 net/bluetooth/hci_event.c:7525 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4015 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5837: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4308 [inline] __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:906 [inline] sk_prot_alloc+0xe0/0x210 net/core/sock.c:2181 sk_alloc+0x38/0x370 net/core/sock.c:2234 bt_sock_alloc+0x3c/0x340 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1878 [inline] l2cap_sock_new_connection_cb+0xe1/0x2b0 net/bluetooth/l2cap_sock.c:1469 l2cap_connect_cfm+0x336/0x1090 net/bluetooth/l2cap_core.c:7223 hci_connect_cfm+0x162/0x240 include/net/bluetooth/hci_core.h:2051 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5763 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5789 hci_event_func net/bluetooth/hci_event.c:7470 [inline] hci_event_packet+0xa55/0x1540 net/bluetooth/hci_event.c:7525 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4015 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 6119: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2367 [inline] slab_free mm/slub.c:4623 [inline] kfree+0x196/0x430 mm/slub.c:4816 sk_prot_free net/core/sock.c:2217 [inline] __sk_destruct+0x479/0x5f0 net/core/sock.c:2309 l2cap_sock_cleanup_listen+0xdd/0x3c0 net/bluetooth/l2cap_sock.c:1449 l2cap_sock_release+0x5d/0x1d0 net/bluetooth/l2cap_sock.c:1412 __sock_release net/socket.c:647 [inline] sock_close+0xbc/0x240 net/socket.c:1398 __fput+0x3e9/0x9f0 fs/file_table.c:464 task_work_run+0x24f/0x310 kernel/task_work.c:227 get_signal+0x15f7/0x1750 kernel/signal.c:2809 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802d7f1000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1408 bytes inside of freed 2048-byte region [ffff88802d7f1000, ffff88802d7f1800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802d7f5000 pfn:0x2d7f0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac42000 ffffea0000a86800 0000000000000002 raw: ffff88802d7f5000 0000000080080004 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac42000 ffffea0000a86800 0000000000000002 head: ffff88802d7f5000 0000000080080004 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000b5fc01 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5884, tgid 5884 (kworker/1:3), ts 99331400940, free_ts 99231087271 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1629 prep_new_page mm/page_alloc.c:1637 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3555 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4817 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2437 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2601 new_slab mm/slub.c:2654 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3840 __slab_alloc+0x58/0xa0 mm/slub.c:3930 __slab_alloc_node mm/slub.c:4005 [inline] slab_alloc_node mm/slub.c:4166 [inline] __do_kmalloc_node mm/slub.c:4307 [inline] __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4327 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:534 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:603 alloc_skb include/linux/skbuff.h:1331 [inline] alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6519 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2897 sock_alloc_send_skb include/net/sock.h:1804 [inline] mld_newpack+0x1c3/0xaf0 net/ipv6/mcast.c:1790 add_grhead net/ipv6/mcast.c:1893 [inline] add_grec+0x1492/0x19a0 net/ipv6/mcast.c:2031 mld_send_cr net/ipv6/mcast.c:2157 [inline] mld_ifc_work+0x691/0xd90 net/ipv6/mcast.c:2697 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 page last free pid 5929 tgid 5928 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1205 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2738 discard_slab mm/slub.c:2698 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3167 put_cpu_partial+0x17c/0x250 mm/slub.c:3242 __slab_free+0x290/0x380 mm/slub.c:4493 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4129 [inline] slab_alloc_node mm/slub.c:4178 [inline] __do_kmalloc_node mm/slub.c:4307 [inline] __kmalloc_node_track_caller_noprof+0x237/0x4c0 mm/slub.c:4327 kmemdup_noprof+0x2a/0x60 mm/util.c:136 mpls_dev_sysctl_register+0xd1/0x280 net/mpls/af_mpls.c:1390 mpls_add_dev net/mpls/af_mpls.c:1460 [inline] mpls_dev_notify+0x33f/0x7a0 net/mpls/af_mpls.c:1600 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2180 [inline] call_netdevice_notifiers net/core/dev.c:2194 [inline] register_netdevice+0x1696/0x1b10 net/core/dev.c:10921 __ip_tunnel_create+0x2b4/0x380 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x21c/0x720 net/ipv4/ip_tunnel.c:1160 ops_init+0x31e/0x590 net/core/net_namespace.c:138 Memory state around the buggy address: ffff88802d7f1480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802d7f1500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802d7f1580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802d7f1600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802d7f1680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================