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BUG: KASAN: slab-use-after-free in __hci_acl_create_connection_sync+0x6e4/0x9c0 net/bluetooth/hci_sync.c:6518
Write of size 2 at addr ffff888037f6c036 by task kworker/u9:5/5107

CPU: 1 PID: 5107 Comm: kworker/u9:5 Not tainted 6.8.0-rc4-next-20240214-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: hci4 hci_cmd_sync_work
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_acl_create_connection_sync+0x6e4/0x9c0 net/bluetooth/hci_sync.c:6518
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:306
 process_one_work kernel/workqueue.c:3146 [inline]
 process_scheduled_works+0x9d7/0x1730 kernel/workqueue.c:3226
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3307
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

Allocated by task 8585:
 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:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x1d9/0x360 mm/slub.c:4013
 kmalloc include/linux/slab.h:590 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 hci_conn_add+0xc7/0x13a0 net/bluetooth/hci_conn.c:914
 hci_conn_add_unset net/bluetooth/hci_conn.c:1016 [inline]
 hci_connect_acl+0x166/0x4b0 net/bluetooth/hci_conn.c:1632
 hci_connect_sco+0x47/0x350 net/bluetooth/hci_conn.c:1694
 sco_connect net/bluetooth/sco.c:266 [inline]
 sco_sock_connect+0x2fc/0x990 net/bluetooth/sco.c:592
 __sys_connect_file net/socket.c:2048 [inline]
 __sys_connect+0x2df/0x310 net/socket.c:2065
 __do_sys_connect net/socket.c:2075 [inline]
 __se_sys_connect net/socket.c:2072 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2072
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Freed by task 5107:
 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:586
 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:2122 [inline]
 slab_free mm/slub.c:4296 [inline]
 kfree+0x14a/0x380 mm/slub.c:4406
 device_release+0x99/0x1c0
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22f/0x480 lib/kobject.c:737
 hci_conn_cleanup net/bluetooth/hci_conn.c:176 [inline]
 hci_conn_del+0x8f0/0xc70 net/bluetooth/hci_conn.c:1126
 hci_abort_conn_sync+0x583/0xde0 net/bluetooth/hci_sync.c:5361
 __hci_acl_create_connection_sync+0x622/0x9c0 net/bluetooth/hci_sync.c:6554
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:306
 process_one_work kernel/workqueue.c:3146 [inline]
 process_scheduled_works+0x9d7/0x1730 kernel/workqueue.c:3226
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3307
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242

The buggy address belongs to the object at ffff888037f6c000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 54 bytes inside of
 freed 4096-byte region [ffff888037f6c000, ffff888037f6d000)

The buggy address belongs to the physical page:
page:ffffea0000dfda00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x37f68
head:ffffea0000dfda00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000840 ffff888014c42140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 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 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1786, tgid 1786 (kworker/1:2), ts 322727451185, free_ts 322715548751
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
 prep_new_page mm/page_alloc.c:1540 [inline]
 get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
 __alloc_pages+0x256/0x6a0 mm/page_alloc.c:4567
 __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:2191
 allocate_slab mm/slub.c:2354 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2407
 ___slab_alloc+0xc73/0x1260 mm/slub.c:3541
 __slab_alloc mm/slub.c:3626 [inline]
 __slab_alloc_node mm/slub.c:3679 [inline]
 slab_alloc_node mm/slub.c:3851 [inline]
 __do_kmalloc_node mm/slub.c:3981 [inline]
 __kmalloc_node_track_caller+0x2d4/0x4e0 mm/slub.c:4002
 kmalloc_reserve+0xf3/0x260 net/core/skbuff.c:582
 __alloc_skb+0x1b1/0x420 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1296 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x254/0xaa0 drivers/net/netdevsim/dev.c:850
 process_one_work kernel/workqueue.c:3146 [inline]
 process_scheduled_works+0x9d7/0x1730 kernel/workqueue.c:3226
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3307
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242
page last free pid 7891 tgid 7891 stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1140 [inline]
 free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486
 discard_slab mm/slub.c:2453 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:2922
 put_cpu_partial+0x17c/0x250 mm/slub.c:2997
 __slab_free+0x2e8/0x3d0 mm/slub.c:4167
 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:3814 [inline]
 slab_alloc_node mm/slub.c:3861 [inline]
 kmem_cache_alloc+0x172/0x350 mm/slub.c:3868
 getname_flags+0xbd/0x4f0 fs/namei.c:140
 user_path_at_empty+0x2c/0x60 fs/namei.c:2917
 user_path_at include/linux/namei.h:57 [inline]
 __do_sys_chdir fs/open.c:559 [inline]
 __se_sys_chdir+0xbf/0x220 fs/open.c:553
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Memory state around the buggy address:
 ffff888037f6bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888037f6bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888037f6c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888037f6c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888037f6c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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