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:1616 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xe57/0x1050 net/bluetooth/l2cap_core.c:7323 Read of size 8 at addr ffff8880276b3480 by task kworker/u9:0/51 CPU: 1 UID: 0 PID: 51 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 02/12/2026 Workqueue: hci0 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 l2cap_conn_ready net/bluetooth/l2cap_core.c:1616 [inline] l2cap_connect_cfm+0xe57/0x1050 net/bluetooth/l2cap_core.c:7323 hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline] le_conn_complete_evt+0x195c/0x1f40 net/bluetooth/hci_event.c:5847 hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5873 hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7473 hci_event_func net/bluetooth/hci_event.c:7781 [inline] hci_event_packet+0x682/0x11c0 net/bluetooth/hci_event.c:7838 hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 51: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:962 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] l2cap_chan_create+0x44/0x940 net/bluetooth/l2cap_core.c:445 l2cap_sock_alloc.constprop.0+0xf5/0x1e0 net/bluetooth/l2cap_sock.c:1924 l2cap_sock_new_connection_cb+0x101/0x260 net/bluetooth/l2cap_sock.c:1503 l2cap_connect_cfm+0x4e2/0x1050 net/bluetooth/l2cap_core.c:7306 hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline] le_conn_complete_evt+0x195c/0x1f40 net/bluetooth/hci_event.c:5847 hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5873 hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7473 hci_event_func net/bluetooth/hci_event.c:7781 [inline] hci_event_packet+0x682/0x11c0 net/bluetooth/hci_event.c:7838 hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 10842: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2670 [inline] slab_free mm/slub.c:6082 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6399 l2cap_chan_destroy net/bluetooth/l2cap_core.c:491 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_chan_put+0x235/0x300 net/bluetooth/l2cap_core.c:516 l2cap_sock_cleanup_listen+0x4d/0x2d0 net/bluetooth/l2cap_sock.c:1486 l2cap_sock_release+0x69/0x280 net/bluetooth/l2cap_sock.c:1444 __sock_release+0xb3/0x260 net/socket.c:662 sock_close+0x1c/0x30 net/socket.c:1455 __fput+0x3ff/0xb40 fs/file_table.c:469 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:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __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 include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880276b3000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1152 bytes inside of freed 2048-byte region [ffff8880276b3000, ffff8880276b3800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x276b0 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 ffff88813fe3a000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe3a000 dead000000000100 dead000000000122 head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea00009dac01 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 3559415531, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1888 prep_new_page mm/page_alloc.c:1896 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249 alloc_slab_page mm/slub.c:3238 [inline] allocate_slab mm/slub.c:3411 [inline] new_slab+0xa6/0x6e0 mm/slub.c:3469 refill_objects+0x26b/0x400 mm/slub.c:7091 refill_sheaf mm/slub.c:2787 [inline] alloc_full_sheaf mm/slub.c:2808 [inline] __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4546 alloc_from_pcs mm/slub.c:4639 [inline] slab_alloc_node mm/slub.c:4773 [inline] __do_kmalloc_node mm/slub.c:5176 [inline] __kmalloc_noprof+0x688/0x850 mm/slub.c:5189 kmalloc_noprof include/linux/slab.h:966 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] serdev_controller_alloc+0x37/0x2a0 drivers/tty/serdev/core.c:471 serdev_tty_port_register+0x60/0x290 drivers/tty/serdev/serdev-ttyport.c:277 tty_port_register_device_attr_serdev+0xd5/0x150 drivers/tty/tty_port.c:187 serial_core_add_one_port drivers/tty/serial/serial_core.c:3107 [inline] serial_core_register_port+0xd41/0x17a0 drivers/tty/serial/serial_core.c:3305 serial8250_register_8250_port+0x155a/0x2260 drivers/tty/serial/8250/8250_core.c:822 serial_pnp_probe+0x436/0x930 drivers/tty/serial/8250/8250_pnp.c:480 pnp_device_probe+0x2b3/0x4a0 drivers/pnp/driver.c:111 call_driver_probe drivers/base/dd.c:583 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:661 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:803 page_owner free stack trace missing Memory state around the buggy address: ffff8880276b3380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880276b3400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880276b3480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880276b3500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880276b3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================