syzbot

 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
kobject: kobject_add_internal failed for hci2:201 with -EEXIST, don't try to register things with the same name in the same directory.
Bluetooth: hci2: failed to register connection device
==================================================================
BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0xd7/0x140 net/bluetooth/l2cap_sock.c:1670
Read of size 8 at addr ffff888020ee7188 by task kworker/u9:4/5237

CPU: 0 UID: 0 PID: 5237 Comm: kworker/u9:4 Not tainted 6.12.0-rc1-syzkaller-00165-g360c1f1f24c6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: hci2 hci_rx_work
Call Trace:
 <TASK>
 __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:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 l2cap_sock_ready_cb+0xd7/0x140 net/bluetooth/l2cap_sock.c:1670
 l2cap_chan_ready net/bluetooth/l2cap_core.c:1256 [inline]
 l2cap_le_start+0x4e2/0x17d0 net/bluetooth/l2cap_core.c:1368
 l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline]
 l2cap_connect_cfm+0x6de/0x1220 net/bluetooth/l2cap_core.c:7278
 hci_connect_cfm+0xa4/0x150 include/net/bluetooth/hci_core.h:1960
 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5758
 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5784
 hci_event_func net/bluetooth/hci_event.c:7440 [inline]
 hci_event_packet+0xa57/0x1540 net/bluetooth/hci_event.c:7495
 hci_rx_work+0x3fe/0xd80 net/bluetooth/hci_core.c:4025
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 7244:
 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:257 [inline]
 __do_kmalloc_node mm/slub.c:4265 [inline]
 __kmalloc_noprof+0x1fc/0x400 mm/slub.c:4277
 kmalloc_noprof include/linux/slab.h:882 [inline]
 sk_prot_alloc+0xe0/0x210 net/core/sock.c:2164
 sk_alloc+0x38/0x370 net/core/sock.c:2217
 bt_sock_alloc+0x3c/0x340 net/bluetooth/af_bluetooth.c:148
 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1877 [inline]
 l2cap_sock_create+0x13f/0x2d0 net/bluetooth/l2cap_sock.c:1917
 bt_sock_create+0x163/0x230 net/bluetooth/af_bluetooth.c:132
 __sock_create+0x492/0x920 net/socket.c:1576
 sock_create net/socket.c:1627 [inline]
 __sys_socket_create net/socket.c:1664 [inline]
 __sys_socket+0x150/0x3c0 net/socket.c:1711
 __do_sys_socket net/socket.c:1725 [inline]
 __se_sys_socket net/socket.c:1723 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1723
 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

Freed by task 7247:
 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:579
 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:230 [inline]
 slab_free_hook mm/slub.c:2343 [inline]
 slab_free mm/slub.c:4580 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4728
 sk_prot_free net/core/sock.c:2200 [inline]
 __sk_destruct+0x479/0x5f0 net/core/sock.c:2292
 l2cap_sock_release+0x15b/0x1d0 net/bluetooth/l2cap_sock.c:1421
 __sock_release net/socket.c:658 [inline]
 sock_close+0xbe/0x240 net/socket.c:1426
 __fput+0x241/0x880 fs/file_table.c:431
 task_work_run+0x251/0x310 kernel/task_work.c:228
 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:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 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 ffff888020ee7000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 392 bytes inside of
 freed 2048-byte region [ffff888020ee7000, ffff888020ee7800)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20ee0
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 ffff88801ac42000 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000080008 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801ac42000 dead000000000100 dead000000000122
head: 0000000000000000 0000000000080008 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea000083b801 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 1, tgid 1 (swapper/0), ts 3565828828, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2413
 allocate_slab+0x5a/0x2f0 mm/slub.c:2579
 new_slab mm/slub.c:2632 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
 __slab_alloc+0x58/0xa0 mm/slub.c:3909
 __slab_alloc_node mm/slub.c:3962 [inline]
 slab_alloc_node mm/slub.c:4123 [inline]
 __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4291
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 acpi_add_single_object+0xe5/0x1e00 drivers/acpi/scan.c:1876
 acpi_bus_check_add+0x32b/0x980 drivers/acpi/scan.c:2181
 acpi_ns_walk_namespace+0x296/0x4f0
 acpi_walk_namespace+0xeb/0x130 drivers/acpi/acpica/nsxfeval.c:606
 acpi_bus_scan+0x4c1/0x560 drivers/acpi/scan.c:2595
 acpi_scan_init+0x267/0x730 drivers/acpi/scan.c:2747
 acpi_init+0x159/0x240 drivers/acpi/bus.c:1466
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888020ee7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020ee7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888020ee7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888020ee7200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020ee7280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================