==================================================================
BUG: KASAN: use-after-free in hci_cmd_timeout+0x1c3/0x1f0 net/bluetooth/hci_core.c:1495
Read of size 2 at addr ffff888039981008 by task kworker/u5:2/3666

CPU: 0 PID: 3666 Comm: kworker/u5:2 Not tainted 6.1.0-rc5-syzkaller-00307-gfe24a97cf254 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: hci6 hci_cmd_timeout
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x220 mm/kasan/report.c:395
 kasan_report+0x139/0x170 mm/kasan/report.c:495
 hci_cmd_timeout+0x1c3/0x1f0 net/bluetooth/hci_core.c:1495
 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Allocated by task 3664:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:371 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:380
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:955 [inline]
 __kmalloc_node_track_caller+0xad/0x190 mm/slab_common.c:975
 kmalloc_reserve net/core/skbuff.c:437 [inline]
 __alloc_skb+0x11d/0x620 net/core/skbuff.c:509
 alloc_skb include/linux/skbuff.h:1267 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:469 [inline]
 hci_cmd_sync_alloc+0x39/0x340 net/bluetooth/hci_sync.c:54
 hci_cmd_sync_add+0xaa/0x240 net/bluetooth/hci_sync.c:95
 __hci_cmd_sync_sk+0xdf/0x680 net/bluetooth/hci_sync.c:157
 __hci_cmd_sync+0x33/0x40 net/bluetooth/hci_sync.c:206
 btintel_enter_mfg+0x2a/0x80 drivers/bluetooth/btintel.c:79
 ag6xx_setup+0x193/0xe40 drivers/bluetooth/hci_ag6xx.c:165
 hci_uart_setup+0x380/0x780 drivers/bluetooth/hci_ldisc.c:423
 hci_dev_setup_sync+0x174/0x7e0 net/bluetooth/hci_sync.c:4490
 hci_dev_init_sync+0xcd/0x6b0 net/bluetooth/hci_sync.c:4566
 hci_dev_open_sync+0x34e/0x8e0 net/bluetooth/hci_sync.c:4664
 hci_dev_do_open net/bluetooth/hci_core.c:483 [inline]
 hci_power_on+0x16a/0x610 net/bluetooth/hci_core.c:984
 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

Freed by task 3664:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:511
 ____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+0x12e/0x1a0 mm/slub.c:1750
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x71/0x110 mm/slub.c:3674
 skb_free_head net/core/skbuff.c:760 [inline]
 skb_release_data+0x536/0x6d0 net/core/skbuff.c:789
 skb_release_all net/core/skbuff.c:854 [inline]
 __kfree_skb net/core/skbuff.c:868 [inline]
 kfree_skb_reason+0xd3/0x290 net/core/skbuff.c:891
 kfree_skb include/linux/skbuff.h:1216 [inline]
 hci_dev_open_sync+0x622/0x8e0 net/bluetooth/hci_sync.c:4699
 hci_dev_do_open net/bluetooth/hci_core.c:483 [inline]
 hci_power_on+0x16a/0x610 net/bluetooth/hci_core.c:984
 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

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:481
 insert_work+0x54/0x3e0 kernel/workqueue.c:1358
 __queue_work+0xaaa/0xd60 kernel/workqueue.c:1517
 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1514 [inline]
 __run_timers+0x7a2/0x980 kernel/time/timer.c:1790
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
 __do_softirq+0x277/0x75b kernel/softirq.c:571

Second to 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:481
 insert_work+0x54/0x3e0 kernel/workqueue.c:1358
 __queue_work+0xaaa/0xd60 kernel/workqueue.c:1517
 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1514 [inline]
 __run_timers+0x7a2/0x980 kernel/time/timer.c:1790
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
 __do_softirq+0x277/0x75b kernel/softirq.c:571

The buggy address belongs to the object at ffff888039981000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 512-byte region [ffff888039981000, ffff888039981200)

The buggy address belongs to the physical page:
page:ffffea0000e66000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x39980
head:ffffea0000e66000 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888012841c80
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 154, tgid 154 (kworker/0:2), ts 221624800504, free_ts 0
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x72b/0x7a0 mm/page_alloc.c:4288
 __alloc_pages+0x259/0x560 mm/page_alloc.c:5555
 alloc_slab_page+0x70/0xf0 mm/slub.c:1794
 allocate_slab+0x5e/0x4b0 mm/slub.c:1939
 new_slab mm/slub.c:1992 [inline]
 ___slab_alloc+0x7f4/0xeb0 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x252/0x310 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc+0x9e/0x1a0 mm/slab_common.c:968
 kmalloc include/linux/slab.h:558 [inline]
 kzalloc include/linux/slab.h:689 [inline]
 fib6_info_alloc+0x2c/0xd0 net/ipv6/ip6_fib.c:156
 ip6_route_info_create+0x43d/0x12e0 net/ipv6/route.c:3749
 addrconf_f6i_alloc+0x473/0x810 net/ipv6/route.c:4571
 ipv6_add_addr+0x456/0xe50 net/ipv6/addrconf.c:1105
 addrconf_add_linklocal+0x2ff/0x630 net/ipv6/addrconf.c:3215
 addrconf_addr_gen+0x2c6/0x410 net/ipv6/addrconf.c:3346
 addrconf_notify+0xb48/0xfe0 net/ipv6/addrconf.c:3635
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455
 call_netdevice_notifiers_info net/core/dev.c:1945 [inline]
 netdev_state_change+0x1ba/0x280 net/core/dev.c:1334
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888039980f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888039980f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888039981000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888039981080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888039981100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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