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_sock_new_connection_cb+0x1f8/0x2b0 net/bluetooth/l2cap_sock.c:1484 Read of size 8 at addr ffff88806005d580 by task kworker/u9:7/5850 CPU: 1 UID: 0 PID: 5850 Comm: kworker/u9:7 Not tainted 6.14.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: hci0 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+0x338/0x1090 net/bluetooth/l2cap_core.c:7223 hci_connect_cfm+0x164/0x240 include/net/bluetooth/hci_core.h:2051 le_conn_complete_evt+0xda8/0x1360 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+0xa56/0x1540 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+0xac0/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5850: 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:4294 [inline] __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [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+0x338/0x1090 net/bluetooth/l2cap_core.c:7223 hci_connect_cfm+0x164/0x240 include/net/bluetooth/hci_core.h:2051 le_conn_complete_evt+0xda8/0x1360 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+0xa56/0x1540 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+0xac0/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 10855: 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:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x196/0x430 mm/slub.c:4757 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+0xbe/0x240 net/socket.c:1398 __fput+0x3eb/0x9f0 fs/file_table.c:464 task_work_run+0x251/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/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 ffff88806005d000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1408 bytes inside of freed 2048-byte region [ffff88806005d000, ffff88806005d800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x60058 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b042000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b042000 0000000000000000 dead000000000001 head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001801601 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 5834, tgid 5834 (syz-executor), ts 74653557098, free_ts 21055664572 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2587 new_slab mm/slub.c:2640 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826 __slab_alloc+0x58/0xa0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_noprof+0x2e6/0x4c0 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] rfkill_alloc+0xb0/0x2e0 net/rfkill/core.c:1002 hci_register_dev+0x3d2/0x8b0 net/bluetooth/hci_core.c:2592 __vhci_create_device drivers/bluetooth/hci_vhci.c:428 [inline] vhci_create_device+0x35b/0x6b0 drivers/bluetooth/hci_vhci.c:470 vhci_get_user drivers/bluetooth/hci_vhci.c:527 [inline] vhci_write+0x3cf/0x490 drivers/bluetooth/hci_vhci.c:607 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xad1/0xd10 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 free_contig_range+0x14c/0x430 mm/page_alloc.c:6678 destroy_args+0x94/0x4b0 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x551/0x590 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x24a/0x930 init/main.c:1257 do_initcall_level+0x157/0x210 init/main.c:1319 do_initcalls+0x71/0xd0 init/main.c:1335 kernel_init_freeable+0x435/0x5d0 init/main.c:1568 kernel_init+0x1d/0x2b0 init/main.c:1457 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff88806005d480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806005d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806005d580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806005d600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806005d680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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