syzbot

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BUG: KASAN: slab-use-after-free in hci_conn_hash_flush+0x89/0x220
Read of size 8 at addr ffff8880733dc000 by task syz-executor386/5007

CPU: 1 PID: 5007 Comm: syz-executor386 Not tainted 6.3.0-syzkaller-12049-g58390c8ce1bd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:351 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:462
 kasan_report+0x176/0x1b0 mm/kasan/report.c:572
 hci_conn_hash_flush+0x89/0x220
 hci_dev_close_sync+0xa35/0x1020 net/bluetooth/hci_sync.c:4941
 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline]
 hci_unregister_dev+0x1ca/0x480 net/bluetooth/hci_core.c:2703
 vhci_release+0x83/0xd0 drivers/bluetooth/hci_vhci.c:669
 __fput+0x3b7/0x890 fs/file_table.c:321
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x68f/0x2290 kernel/exit.c:871
 do_group_exit+0x206/0x2c0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f905be26519
Code: Unable to access opcode bytes at 0x7f905be264ef.
RSP: 002b:00007ffd7fa2a1d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f905beaf150 RCX: 00007f905be26519
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000007
RBP: 0000000000000007 R08: ffffffffffffffb8 R09: 001d00000000000c
R10: 00007ffd7fa2a260 R11: 0000000000000246 R12: 00007f905beaf150
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
 </TASK>

Allocated by task 5027:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 hci_conn_add+0xc3/0x13a0 net/bluetooth/hci_conn.c:986
 hci_connect_sco+0x8e/0x2b0 net/bluetooth/hci_conn.c:1663
 sco_connect net/bluetooth/sco.c:264 [inline]
 sco_sock_connect+0x2b9/0x990 net/bluetooth/sco.c:610
 __sys_connect_file net/socket.c:2003 [inline]
 __sys_connect+0x2cd/0x300 net/socket.c:2020
 __do_sys_connect net/socket.c:2030 [inline]
 __se_sys_connect net/socket.c:2027 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2027
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 5007:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:162 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook mm/slub.c:1807 [inline]
 slab_free mm/slub.c:3786 [inline]
 __kmem_cache_free+0x264/0x3c0 mm/slub.c:3799
 device_release+0x95/0x1c0
 kobject_cleanup lib/kobject.c:683 [inline]
 kobject_release lib/kobject.c:714 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x228/0x470 lib/kobject.c:731
 hci_conn_del+0x321/0x5a0 net/bluetooth/hci_conn.c:1162
 hci_conn_unlink+0x1e1/0x320 net/bluetooth/hci_conn.c:1087
 hci_conn_hash_flush+0x198/0x220 net/bluetooth/hci_conn.c:2479
 hci_dev_close_sync+0xa35/0x1020 net/bluetooth/hci_sync.c:4941
 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline]
 hci_unregister_dev+0x1ca/0x480 net/bluetooth/hci_core.c:2703
 vhci_release+0x83/0xd0 drivers/bluetooth/hci_vhci.c:669
 __fput+0x3b7/0x890 fs/file_table.c:321
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x68f/0x2290 kernel/exit.c:871
 do_group_exit+0x206/0x2c0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff8880733dc000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 0 bytes inside of
 freed 4096-byte region [ffff8880733dc000, ffff8880733dd000)

The buggy address belongs to the physical page:
page:ffffea0001ccf600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x733d8
head:ffffea0001ccf600 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000010200 ffff888012442140 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5027, tgid 5027 (syz-executor386), ts 60010982894, free_ts 12760290779
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1722
 prep_new_page mm/page_alloc.c:1729 [inline]
 get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3493
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4759
 alloc_slab_page+0x6a/0x160 mm/slub.c:1851
 allocate_slab mm/slub.c:1998 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2051
 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192
 __slab_alloc mm/slub.c:3291 [inline]
 __slab_alloc_node mm/slub.c:3344 [inline]
 slab_alloc_node mm/slub.c:3441 [inline]
 __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490
 __do_kmalloc_node mm/slab_common.c:965 [inline]
 __kmalloc+0xa8/0x230 mm/slab_common.c:979
 kmalloc include/linux/slab.h:563 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x254/0x4e0 security/tomoyo/file.c:771
 security_file_open+0x63/0xa0 security/security.c:2797
 do_dentry_open+0x308/0x10f0 fs/open.c:907
 do_open fs/namei.c:3636 [inline]
 path_openat+0x27b3/0x3170 fs/namei.c:3791
 do_filp_open+0x234/0x490 fs/namei.c:3818
 do_sys_openat2+0x13f/0x500 fs/open.c:1356
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x247/0x290 fs/open.c:1383
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1302 [inline]
 free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2555
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2650
 free_contig_range+0x9e/0x150 mm/page_alloc.c:6985
 destroy_args+0x102/0x9a0 mm/debug_vm_pgtable.c:1023
 debug_vm_pgtable+0x405/0x490 mm/debug_vm_pgtable.c:1403
 do_one_initcall+0x23d/0x7d0 init/main.c:1246
 do_initcall_level+0x157/0x210 init/main.c:1319
 do_initcalls+0x3f/0x80 init/main.c:1335
 kernel_init_freeable+0x43b/0x5d0 init/main.c:1571
 kernel_init+0x1d/0x2a0 init/main.c:1462
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Memory state around the buggy address:
 ffff8880733dbf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880733dbf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880733dc000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8880733dc080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880733dc100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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