ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 kobject: kobject_add_internal failed for hci1:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci1: failed to register connection device ================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_new_connection_cb+0x1f9/0x2b0 net/bluetooth/l2cap_sock.c:1497 Read of size 8 at addr ffff888143f86588 by task kworker/u9:2/5836 CPU: 1 UID: 0 PID: 5836 Comm: kworker/u9:2 Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: hci1 hci_rx_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 l2cap_sock_new_connection_cb+0x1f9/0x2b0 net/bluetooth/l2cap_sock.c:1497 l2cap_connect_cfm+0x37a/0x1040 net/bluetooth/l2cap_core.c:7264 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2051 le_conn_complete_evt+0xcd3/0x1220 net/bluetooth/hci_event.c:5791 hci_le_conn_complete_evt+0x187/0x450 net/bluetooth/hci_event.c:5817 hci_event_func net/bluetooth/hci_event.c:7508 [inline] hci_event_packet+0x78f/0x1200 net/bluetooth/hci_event.c:7565 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4030 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5836: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] sk_prot_alloc+0xe7/0x220 net/core/sock.c:2247 sk_alloc+0x3a/0x370 net/core/sock.c:2303 bt_sock_alloc+0x3b/0x310 net/bluetooth/af_bluetooth.c:151 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1891 [inline] l2cap_sock_new_connection_cb+0xe2/0x2b0 net/bluetooth/l2cap_sock.c:1482 l2cap_connect_cfm+0x37a/0x1040 net/bluetooth/l2cap_core.c:7264 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2051 le_conn_complete_evt+0xcd3/0x1220 net/bluetooth/hci_event.c:5791 hci_le_conn_complete_evt+0x187/0x450 net/bluetooth/hci_event.c:5817 hci_event_func net/bluetooth/hci_event.c:7508 [inline] hci_event_packet+0x78f/0x1200 net/bluetooth/hci_event.c:7565 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4030 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 7925: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 sk_prot_free net/core/sock.c:2286 [inline] __sk_destruct+0x4e1/0x660 net/core/sock.c:2381 l2cap_sock_cleanup_listen+0xda/0x3e0 net/bluetooth/l2cap_sock.c:1462 l2cap_sock_release+0x5d/0x1d0 net/bluetooth/l2cap_sock.c:1425 __sock_release net/socket.c:647 [inline] sock_close+0xc0/0x240 net/socket.c:1391 __fput+0x44c/0xa70 fs/file_table.c:467 task_work_run+0x1d1/0x260 kernel/task_work.c:227 get_signal+0x11ed/0x1340 kernel/signal.c:2807 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888143f86000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1416 bytes inside of freed 2048-byte region [ffff888143f86000, ffff888143f86800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x143f80 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 057ff00000000040 ffff88801a442000 ffffea00050eba00 dead000000000002 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 057ff00000000040 ffff88801a442000 ffffea00050eba00 dead000000000002 head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 057ff00000000003 ffffea00050fe001 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 11059359965, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] __tty_alloc_driver+0x2d5/0x410 drivers/tty/tty_io.c:3366 hso_init+0x20/0x360 drivers/net/usb/hso.c:3233 do_one_initcall+0x233/0x820 init/main.c:1273 do_initcall_level+0x137/0x1f0 init/main.c:1335 do_initcalls+0x69/0xd0 init/main.c:1351 kernel_init_freeable+0x3d9/0x570 init/main.c:1583 kernel_init+0x1d/0x1d0 init/main.c:1473 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page_owner free stack trace missing Memory state around the buggy address: ffff888143f86480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888143f86500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888143f86580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888143f86600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888143f86680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================