kobject: kobject_add_internal failed for hci4:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci4: failed to register connection device ================================================================== BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xe47/0x1010 net/bluetooth/l2cap_core.c:7305 Read of size 8 at addr ffff88807aa47480 by task kworker/u9:0/11292 CPU: 0 UID: 0 PID: 11292 Comm: kworker/u9:0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: hci4 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline] l2cap_connect_cfm+0xe47/0x1010 net/bluetooth/l2cap_core.c:7305 hci_connect_cfm include/net/bluetooth/hci_core.h:2131 [inline] le_conn_complete_evt+0x1991/0x1fa0 net/bluetooth/hci_event.c:5821 hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5847 hci_le_meta_evt+0x357/0x610 net/bluetooth/hci_event.c:7408 hci_event_func net/bluetooth/hci_event.c:7716 [inline] hci_event_packet+0x685/0x1210 net/bluetooth/hci_event.c:7773 hci_rx_work+0x2c9/0x1020 net/bluetooth/hci_core.c:4076 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 11292: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] l2cap_chan_create+0x44/0x930 net/bluetooth/l2cap_core.c:445 l2cap_sock_alloc.constprop.0+0xf5/0x1d0 net/bluetooth/l2cap_sock.c:1906 l2cap_sock_new_connection_cb+0x101/0x240 net/bluetooth/l2cap_sock.c:1485 l2cap_connect_cfm+0x4f0/0x1010 net/bluetooth/l2cap_core.c:7288 hci_connect_cfm include/net/bluetooth/hci_core.h:2131 [inline] le_conn_complete_evt+0x1991/0x1fa0 net/bluetooth/hci_event.c:5821 hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5847 hci_le_meta_evt+0x357/0x610 net/bluetooth/hci_event.c:7408 hci_event_func net/bluetooth/hci_event.c:7716 [inline] hci_event_packet+0x685/0x1210 net/bluetooth/hci_event.c:7773 hci_rx_work+0x2c9/0x1020 net/bluetooth/hci_core.c:4076 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Freed by task 20212: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6668 [inline] kfree+0x2f8/0x6e0 mm/slub.c:6876 l2cap_chan_destroy net/bluetooth/l2cap_core.c:491 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_chan_put+0x1bb/0x310 net/bluetooth/l2cap_core.c:516 l2cap_sock_cleanup_listen+0x4d/0x2f0 net/bluetooth/l2cap_sock.c:1468 l2cap_sock_release+0x69/0x280 net/bluetooth/l2cap_sock.c:1426 __sock_release+0xb3/0x270 net/socket.c:662 sock_close+0x1c/0x30 net/socket.c:1455 __fput+0x402/0xb70 fs/file_table.c:468 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xfb/0x540 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807aa47000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1152 bytes inside of freed 2048-byte region [ffff88807aa47000, ffff88807aa47800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7aa40 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 ffff88813ff27000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff27000 dead000000000100 dead000000000122 head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001ea9001 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 994, tgid 994 (kworker/u8:5), ts 416570070813, free_ts 409172414534 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4656 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_noprof+0x4fc/0x910 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ieee802_11_parse_elems_full+0x1db/0x3780 net/mac80211/parse.c:1031 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2469 [inline] ieee80211_inform_bss+0x15a/0x1150 net/mac80211/scan.c:79 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline] cfg80211_inform_single_bss_data+0x8e9/0x1d30 net/wireless/scan.c:2373 cfg80211_inform_bss_data+0x22b/0x3be0 net/wireless/scan.c:3228 cfg80211_inform_bss_frame_data+0x26f/0x720 net/wireless/scan.c:3319 ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:230 ieee80211_scan_rx+0x4cf/0xb30 net/mac80211/scan.c:359 __ieee80211_rx_handle_packet net/mac80211/rx.c:5282 [inline] ieee80211_rx_list+0x1c40/0x2ed0 net/mac80211/rx.c:5539 page last free pid 9033 tgid 9018 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943 discard_slab mm/slub.c:3346 [inline] __put_partials+0x130/0x170 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x25e/0x770 mm/slub.c:5270 ptlock_alloc+0x1f/0x70 mm/memory.c:7377 ptlock_init include/linux/mm.h:3280 [inline] pagetable_pte_ctor include/linux/mm.h:3334 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:79 [inline] pte_alloc_one+0x84/0x3d0 arch/x86/mm/pgtable.c:18 do_fault_around mm/memory.c:5707 [inline] do_read_fault mm/memory.c:5746 [inline] do_fault+0x8b8/0x1ad0 mm/memory.c:5889 do_pte_missing mm/memory.c:4401 [inline] handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 Memory state around the buggy address: ffff88807aa47380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807aa47400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807aa47480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807aa47500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807aa47580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================