==================================================================
BUG: KASAN: slab-use-after-free in hci_cmd_timeout+0x1d9/0x1e0 net/bluetooth/hci_core.c:1526
Read of size 2 at addr ffff8880345852b8 by task kworker/u9:5/5104

CPU: 1 PID: 5104 Comm: kworker/u9:5 Not tainted 6.9.0-syzkaller-02100-g4b95dc87362a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: hci0 hci_cmd_timeout
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 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
 hci_cmd_timeout+0x1d9/0x1e0 net/bluetooth/hci_core.c:1526
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 5109:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3871 [inline]
 slab_alloc_node mm/slub.c:3918 [inline]
 kmem_cache_alloc+0x174/0x350 mm/slub.c:3925
 skb_clone+0x20c/0x390 net/core/skbuff.c:2075
 hci_send_cmd_sync net/bluetooth/hci_core.c:4219 [inline]
 hci_cmd_work+0x29e/0x670 net/bluetooth/hci_core.c:4239
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 22823:
 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+0xa6/0xe0 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2121 [inline]
 slab_free mm/slub.c:4353 [inline]
 kmem_cache_free+0x10b/0x2d0 mm/slub.c:4417
 kfree_skb include/linux/skbuff.h:1268 [inline]
 __hci_req_sync+0x62f/0x950 net/bluetooth/hci_request.c:184
 hci_req_sync+0xa9/0xd0 net/bluetooth/hci_request.c:206
 hci_inquiry+0x44b/0x870 net/bluetooth/hci_core.c:425
 sock_do_ioctl+0x158/0x460 net/socket.c:1222
 sock_ioctl+0x629/0x8e0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888034585280
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 56 bytes inside of
 freed 240-byte region [ffff888034585280, ffff888034585370)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x34585
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888019a95780 dead000000000100 dead000000000122
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 11573, tgid 11573 (kworker/u8:13), ts 540273268279, free_ts 540172904341
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page+0x5f/0x160 mm/slub.c:2190
 allocate_slab mm/slub.c:2353 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2406
 ___slab_alloc+0xb07/0x12e0 mm/slub.c:3592
 __slab_alloc mm/slub.c:3682 [inline]
 __slab_alloc_node mm/slub.c:3735 [inline]
 slab_alloc_node mm/slub.c:3908 [inline]
 kmem_cache_alloc_node+0x24a/0x390 mm/slub.c:3961
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:658
 alloc_skb include/linux/skbuff.h:1319 [inline]
 nlmsg_new include/net/netlink.h:1010 [inline]
 rtmsg_ifinfo_build_skb+0x89/0x290 net/core/rtnetlink.c:4048
 unregister_netdevice_many_notify+0xe3e/0x16e0 net/core/dev.c:11109
 unregister_netdevice_many net/core/dev.c:11163 [inline]
 default_device_exit_batch+0xa0f/0xa90 net/core/dev.c:11640
 ops_exit_list net/core/net_namespace.c:178 [inline]
 cleanup_net+0x89d/0xcc0 net/core/net_namespace.c:640
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
page last free pid 11573 tgid 11573 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x97b/0xaa0 mm/page_alloc.c:2347
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
 discard_slab mm/slub.c:2452 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:2920
 put_cpu_partial+0x17c/0x250 mm/slub.c:2995
 __slab_free+0x2ea/0x3d0 mm/slub.c:4224
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x5e/0xc0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3871 [inline]
 slab_alloc_node mm/slub.c:3918 [inline]
 kmalloc_trace+0x16f/0x370 mm/slub.c:4065
 kmalloc include/linux/slab.h:628 [inline]
 kzalloc include/linux/slab.h:749 [inline]
 mld_add_delrec net/ipv6/mcast.c:742 [inline]
 igmp6_leave_group net/ipv6/mcast.c:2624 [inline]
 igmp6_group_dropped+0x3a6/0xef0 net/ipv6/mcast.c:722
 __ipv6_dev_mc_dec+0x2bd/0x340 net/ipv6/mcast.c:978
 addrconf_leave_solict net/ipv6/addrconf.c:2251 [inline]
 __ipv6_ifa_notify+0x912/0x11f0 net/ipv6/addrconf.c:6282
 addrconf_ifdown+0xeea/0x1bc0 net/ipv6/addrconf.c:3978
 addrconf_notify+0x3cb/0x1020
 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
 call_netdevice_notifiers net/core/dev.c:2002 [inline]
 dev_close_many+0x33c/0x4c0 net/core/dev.c:1543

Memory state around the buggy address:
 ffff888034585180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888034585200: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff888034585280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff888034585300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff888034585380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
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