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Bluetooth: hci2: failed to register connection device
==================================================================
BUG: KASAN: use-after-free in l2cap_sock_new_connection_cb+0x1ef/0x2a0 net/bluetooth/l2cap_sock.c:1517
Read of size 8 at addr ffff8880755d3540 by task kworker/u5:5/4262

CPU: 1 PID: 4262 Comm: kworker/u5:5 Not tainted 6.1.117-syzkaller #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:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 l2cap_sock_new_connection_cb+0x1ef/0x2a0 net/bluetooth/l2cap_sock.c:1517
 l2cap_connect_cfm+0x36b/0x1270 net/bluetooth/l2cap_core.c:8326
 hci_connect_cfm+0x9e/0x150 include/net/bluetooth/hci_core.h:1788
 le_conn_complete_evt+0xd54/0x1320 net/bluetooth/hci_event.c:6008
 hci_le_conn_complete_evt+0x188/0x410 net/bluetooth/hci_event.c:6034
 hci_event_func net/bluetooth/hci_event.c:7533 [inline]
 hci_event_packet+0xa40/0x1510 net/bluetooth/hci_event.c:7588
 hci_rx_work+0x3cd/0xce0 net/bluetooth/hci_core.c:4100
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 4262:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:936 [inline]
 __kmalloc+0xb2/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:562 [inline]
 sk_prot_alloc+0xe0/0x200 net/core/sock.c:2047
 sk_alloc+0x36/0x350 net/core/sock.c:2100
 bt_sock_alloc+0x37/0x130 net/bluetooth/af_bluetooth.c:148
 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1911 [inline]
 l2cap_sock_new_connection_cb+0xd8/0x2a0 net/bluetooth/l2cap_sock.c:1502
 l2cap_connect_cfm+0x36b/0x1270 net/bluetooth/l2cap_core.c:8326
 hci_connect_cfm+0x9e/0x150 include/net/bluetooth/hci_core.h:1788
 le_conn_complete_evt+0xd54/0x1320 net/bluetooth/hci_event.c:6008
 hci_le_conn_complete_evt+0x188/0x410 net/bluetooth/hci_event.c:6034
 hci_event_func net/bluetooth/hci_event.c:7533 [inline]
 hci_event_packet+0xa40/0x1510 net/bluetooth/hci_event.c:7588
 hci_rx_work+0x3cd/0xce0 net/bluetooth/hci_core.c:4100
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 5682:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 sk_prot_free net/core/sock.c:2083 [inline]
 __sk_destruct+0x473/0x5f0 net/core/sock.c:2169
 l2cap_sock_cleanup_listen+0xd9/0x270 net/bluetooth/l2cap_sock.c:1482
 l2cap_sock_release+0x59/0x1d0 net/bluetooth/l2cap_sock.c:1445
 __sock_release net/socket.c:654 [inline]
 sock_close+0xcd/0x230 net/socket.c:1400
 __fput+0x3f6/0x8d0 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:203
 get_signal+0x15fc/0x17d0 kernel/signal.c:2648
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845
 netdev_for_each_tx_queue include/linux/netdevice.h:2453 [inline]
 dev_shutdown+0x9d/0x440 net/sched/sch_generic.c:1489
 unregister_netdevice_many+0xaac/0x17a0 net/core/dev.c:10881
 unregister_netdevice_queue+0x2e6/0x350 net/core/dev.c:10821
 unregister_netdevice include/linux/netdevice.h:3045 [inline]
 __tun_detach+0x6b6/0x1600 drivers/net/tun.c:685
 tun_detach drivers/net/tun.c:701 [inline]
 tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3492
 __fput+0x3f6/0x8d0 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff8880755d3000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1344 bytes inside of
 2048-byte region [ffff8880755d3000, ffff8880755d3800)

The buggy address belongs to the physical page:
page:ffffea0001d57400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x755d0
head:ffffea0001d57400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001677a00 dead000000000002 ffff888017c42000
raw: 0000000000000000 0000000000080008 00000001ffffffff 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4256, tgid 4256 (syz-executor), ts 67947371868, free_ts 67896159961
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4313
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5589
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc_node_track_caller+0xa0/0x220 mm/slab_common.c:956
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 pskb_expand_head+0x18c/0x10e0 net/core/skbuff.c:1848
 netlink_trim+0x183/0x220 net/netlink/af_netlink.c:1308
 netlink_broadcast+0x5b/0x10b0 net/netlink/af_netlink.c:1502
 nlmsg_multicast include/net/netlink.h:1071 [inline]
 nlmsg_notify+0xfb/0x1c0 net/netlink/af_netlink.c:2551
 __dev_notify_flags+0xdd/0x610 net/core/dev.c:8627
 rtnl_newlink_create net/core/rtnetlink.c:3427 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3639 [inline]
 rtnl_newlink+0x1946/0x2050 net/core/rtnetlink.c:3652
 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6150
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3464
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x137/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa1/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:562 [inline]
 load_elf_phdrs fs/binfmt_elf.c:481 [inline]
 load_elf_binary+0x2ec/0x2720 fs/binfmt_elf.c:861
 search_binary_handler fs/exec.c:1741 [inline]
 exec_binprm fs/exec.c:1782 [inline]
 bprm_execve+0x96a/0x18a0 fs/exec.c:1851
 kernel_execve+0x8e6/0xa10 fs/exec.c:2016
 call_usermodehelper_exec_async+0x22f/0x370 kernel/umh.c:113
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff8880755d3400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880755d3480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880755d3500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff8880755d3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880755d3600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================