ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 kobject: 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: 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+0x6d0/0x10e0 net/bluetooth/l2cap_core.c:7305 Read of size 8 at addr ffff888028ea0500 by task kworker/u9:2/5805 CPU: 1 UID: 0 PID: 5805 Comm: kworker/u9:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: hci0 hci_rx_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline] l2cap_connect_cfm+0x6d0/0x10e0 net/bluetooth/l2cap_core.c:7305 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2131 le_conn_complete_evt+0xf65/0x1420 net/bluetooth/hci_event.c:5821 hci_le_conn_complete_evt+0x187/0x480 net/bluetooth/hci_event.c:5847 hci_event_func net/bluetooth/hci_event.c:7716 [inline] hci_event_packet+0x78f/0x1260 net/bluetooth/hci_event.c:7773 hci_rx_work+0x3ee/0x1060 net/bluetooth/hci_core.c:4076 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 5805: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __kmalloc_cache_noprof+0x1fb/0x6d0 mm/slub.c:5776 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] l2cap_chan_create+0x51/0x7a0 net/bluetooth/l2cap_core.c:445 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1906 [inline] l2cap_sock_new_connection_cb+0x182/0x2e0 net/bluetooth/l2cap_sock.c:1485 l2cap_connect_cfm+0x367/0x10e0 net/bluetooth/l2cap_core.c:7288 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2131 le_conn_complete_evt+0xf65/0x1420 net/bluetooth/hci_event.c:5821 hci_le_conn_complete_evt+0x187/0x480 net/bluetooth/hci_event.c:5847 hci_event_func net/bluetooth/hci_event.c:7716 [inline] hci_event_packet+0x78f/0x1260 net/bluetooth/hci_event.c:7773 hci_rx_work+0x3ee/0x1060 net/bluetooth/hci_core.c:4076 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Freed by task 6380: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/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+0x1bd/0x900 mm/slub.c:6876 l2cap_sock_cleanup_listen+0xf0/0x450 net/bluetooth/l2cap_sock.c:1468 l2cap_sock_release+0x6e/0x270 net/bluetooth/l2cap_sock.c:1426 __sock_release net/socket.c:662 [inline] sock_close+0xc3/0x240 net/socket.c:1455 __fput+0x45b/0xa80 fs/file_table.c:468 task_work_run+0x1d4/0x260 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+0xff/0x4f0 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+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888028ea0000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1280 bytes inside of freed 2048-byte region [ffff888028ea0000, ffff888028ea0800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28ea0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813ff27000 ffffea0000a1bc00 dead000000000002 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813ff27000 ffffea0000a1bc00 dead000000000002 head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 0080000000000003 ffffea0000a3a801 00000000ffffffff 00000000ffffffff head: 0000000000000000 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 815, tgid 815 (kworker/u8:6), ts 15560210005, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xb10/0x1400 mm/slub.c:4656 __slab_alloc+0xc6/0x1f0 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+0x15f/0x7e0 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] scsi_alloc_target+0x138/0xbb0 drivers/scsi/scsi_scan.c:508 __scsi_scan_target+0x15b/0xd10 drivers/scsi/scsi_scan.c:1772 scsi_scan_channel drivers/scsi/scsi_scan.c:1877 [inline] scsi_scan_host_selected+0x375/0x690 drivers/scsi/scsi_scan.c:1906 do_scsi_scan_host drivers/scsi/scsi_scan.c:2045 [inline] do_scan_async+0x124/0x760 drivers/scsi/scsi_scan.c:2055 async_run_entry_fn+0xa8/0x450 kernel/async.c:129 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 page_owner free stack trace missing Memory state around the buggy address: ffff888028ea0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028ea0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888028ea0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888028ea0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028ea0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================