==================================================================
BUG: KASAN: slab-use-after-free in cfusbl_device_notify+0x150/0x6a0 net/caif/caif_usb.c:142
Read of size 8 at addr ffff88804cd40c50 by task syz.2.600/8032

CPU: 0 UID: 0 PID: 8032 Comm: syz.2.600 Not tainted 6.15.0-syzkaller-07802-g558428921edd #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 cfusbl_device_notify+0x150/0x6a0 net/caif/caif_usb.c:142
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
 call_netdevice_notifiers net/core/dev.c:2282 [inline]
 register_netdevice+0x121c/0x1ae0 net/core/dev.c:11100
 register_netdev+0x40/0x60 net/core/dev.c:11221
 bnep_add_connection+0x6bf/0xbf0 net/bluetooth/bnep/core.c:624
 do_bnep_sock_ioctl+0x40e/0x640 net/bluetooth/bnep/sock.c:83
 sock_do_ioctl+0xdc/0x300 net/socket.c:1190
 sock_ioctl+0x576/0x790 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8d5d18e969
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8d5e093038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8d5d3b6080 RCX: 00007f8d5d18e969
RDX: 0000200000000540 RSI: 00000000400442c8 RDI: 000000000000000a
RBP: 00007f8d5d210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8d5d3b6080 R15: 00007ffc670928a8
 </TASK>

Allocated by task 5836:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 __hci_conn_add+0x233/0x1b30 net/bluetooth/hci_conn.c:939
 hci_conn_request_evt+0x53e/0xb60 net/bluetooth/hci_event.c:3316
 hci_event_func net/bluetooth/hci_event.c:7511 [inline]
 hci_event_packet+0x7e3/0x1200 net/bluetooth/hci_event.c:7565
 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4036
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 7988:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2380 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x18e/0x440 mm/slub.c:4841
 device_release+0x9c/0x1c0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22b/0x480 lib/kobject.c:737
 hci_conn_cleanup net/bluetooth/hci_conn.c:175 [inline]
 hci_conn_del+0x8ff/0xcb0 net/bluetooth/hci_conn.c:1173
 hci_conn_hash_flush+0x191/0x230 net/bluetooth/hci_conn.c:2544
 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5225
 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline]
 hci_unregister_dev+0x206/0x500 net/bluetooth/hci_core.c:2678
 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665
 __fput+0x44c/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x8d1/0x2550 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
 __do_sys_exit_group kernel/exit.c:1119 [inline]
 __se_sys_exit_group kernel/exit.c:1117 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1117
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
 insert_work+0x3d/0x330 kernel/workqueue.c:2183
 __queue_work+0xcfc/0xfe0 kernel/workqueue.c:2341
 queue_delayed_work_on+0x18b/0x280 kernel/workqueue.c:2561
 l2cap_chan_del+0x285/0x5e0 net/bluetooth/l2cap_core.c:671
 l2cap_conn_del+0x388/0x680 net/bluetooth/l2cap_core.c:1787
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2065 [inline]
 hci_conn_hash_flush+0x10a/0x230 net/bluetooth/hci_conn.c:2543
 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5225
 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline]
 hci_unregister_dev+0x206/0x500 net/bluetooth/hci_core.c:2678
 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665
 __fput+0x44c/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x8d1/0x2550 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
 __do_sys_exit_group kernel/exit.c:1119 [inline]
 __se_sys_exit_group kernel/exit.c:1117 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1117
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88804cd40000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 3152 bytes inside of
 freed 8192-byte region [ffff88804cd40000, ffff88804cd42000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4cd40
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 ffff88801a442280 ffffea00012fe200 0000000000000004
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a442280 ffffea00012fe200 0000000000000004
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001335001 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 7050, tgid 7048 (syz.3.345), ts 116974548303, free_ts 116968749681
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1710
 prep_new_page mm/page_alloc.c:1718 [inline]
 get_page_from_freelist+0x21e0/0x22c0 mm/page_alloc.c:3680
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2618
 new_slab mm/slub.c:2672 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858
 __slab_alloc mm/slub.c:3948 [inline]
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kmalloc_array_noprof include/linux/slab.h:948 [inline]
 batadv_hash_new+0x7b/0x290 net/batman-adv/hash.c:52
 batadv_tt_local_init net/batman-adv/translation-table.c:539 [inline]
 batadv_tt_init+0x54/0x2a0 net/batman-adv/translation-table.c:4107
 batadv_mesh_init+0x3a6/0x700 net/batman-adv/main.c:198
 batadv_meshif_init_late+0xa3a/0xee0 net/batman-adv/mesh-interface.c:813
 register_netdevice+0x6bf/0x1ae0 net/core/dev.c:11032
 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3823
 __rtnl_newlink net/core/rtnetlink.c:3940 [inline]
 rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944
 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534
page last free pid 5847 tgid 5847 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1254 [inline]
 __free_frozen_pages+0xc6e/0xe50 mm/page_alloc.c:2717
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203
 getname_flags+0xb8/0x540 fs/namei.c:146
 getname include/linux/fs.h:2879 [inline]
 getname_maybe_null include/linux/fs.h:2886 [inline]
 vfs_fstatat+0x43/0x170 fs/stat.c:370
 __do_sys_newfstatat fs/stat.c:542 [inline]
 __se_sys_newfstatat fs/stat.c:536 [inline]
 __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804cd40b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804cd40b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804cd40c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88804cd40c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804cd40d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================