KASAN: slab-use-after-free Read in hci_conn_hash_flush
From: Sanan Hasanov
Date: Tue Sep 12 2023 - 19:02:38 EST
Good day, dear maintainers,
We found a bug using a modified kernel configuration file used by syzbot.
We enhanced the coverage of the configuration file using our tool, klocalizer.
Kernel Branch: 6.3.0-next-20230426
Kernel Config: https://drive.google.com/file/d/19nzVDVMtaTo8fv7RMtXDGYQzeRnNpp-r/view?usp=sharing
Reproducer: https://drive.google.com/file/d/1vzoYO_aW6XQqR6NAaJqvacOcJy9J6R-0/view?usp=sharing
Thank you!
Best regards,
Sanan Hasanov
==================================================================
BUG: KASAN: slab-use-after-free in hci_conn_hash_flush+0x1fa/0x230
Read of size 8 at addr ffff8880780da000 by task syz-executor.7/5990
CPU: 3 PID: 5990 Comm: syz-executor.7 Not tainted 6.3.0-next-20230426 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x178/0x260
print_report+0xc1/0x5e0
kasan_report+0xc0/0xf0
hci_conn_hash_flush+0x1fa/0x230
hci_dev_close_sync+0x5c2/0x1060
hci_unregister_dev+0x1ce/0x4a0
vhci_release+0x80/0xf0
__fput+0x27c/0xa90
task_work_run+0x168/0x260
do_exit+0xbd9/0x2b20
do_group_exit+0xd4/0x2a0
__x64_sys_exit_group+0x3e/0x50
do_syscall_64+0x39/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff463e8edcd
Code: Unable to access opcode bytes at 0x7ff463e8eda3.
RSP: 002b:00007ffde1873c18 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffde1874480 RCX: 00007ff463e8edcd
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000043
RBP: 0000000000000003 R08: 0000000000000026 R09: 00007ffde1874480
R10: 0000000000000026 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ff463eeba70 R14: 0000000000000002 R15: 00007ffde18744c0
</TASK>
Allocated by task 24391:
kasan_save_stack+0x22/0x40
kasan_set_track+0x25/0x30
__kasan_kmalloc+0x7c/0x90
hci_conn_add+0xa5/0x1570
hci_connect_sco+0x3e4/0xf50
sco_sock_connect+0x2c0/0x9c0
__sys_connect_file+0x153/0x1a0
__sys_connect+0x165/0x1a0
__x64_sys_connect+0x72/0xb0
do_syscall_64+0x39/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Freed by task 5990:
kasan_save_stack+0x22/0x40
kasan_set_track+0x25/0x30
kasan_save_free_info+0x2b/0x40
____kasan_slab_free+0x120/0x180
__kmem_cache_free+0xcf/0x280
device_release+0xa3/0x240
kobject_put+0x175/0x270
put_device+0x1f/0x30
hci_conn_del+0x2df/0x860
hci_conn_unlink+0x25b/0x3e0
hci_conn_unlink+0x2ef/0x3e0
hci_conn_hash_flush+0x18d/0x230
hci_dev_close_sync+0x5c2/0x1060
hci_unregister_dev+0x1ce/0x4a0
vhci_release+0x80/0xf0
__fput+0x27c/0xa90
task_work_run+0x168/0x260
do_exit+0xbd9/0x2b20
do_group_exit+0xd4/0x2a0
__x64_sys_exit_group+0x3e/0x50
do_syscall_64+0x39/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Last potentially related work creation:
kasan_save_stack+0x22/0x40
__kasan_record_aux_stack+0x60/0x70
insert_work+0x48/0x360
__queue_work+0x5bc/0xfe0
__queue_delayed_work+0x1c8/0x270
queue_delayed_work_on+0x162/0x1c0
sco_chan_del+0x1db/0x430
__sco_sock_close+0x11f/0x640
sco_sock_release+0x9f/0x2d0
__sock_release+0xcd/0x290
sock_close+0x1c/0x20
__fput+0x27c/0xa90
task_work_run+0x168/0x260
get_signal+0x1cb/0x2460
arch_do_signal_or_restart+0x79/0x5a0
exit_to_user_mode_prepare+0x128/0x1e0
syscall_exit_to_user_mode+0x1a/0x40
do_syscall_64+0x46/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The buggy address belongs to the object at ffff8880780da000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 0 bytes inside of
freed 4096-byte region [ffff8880780da000, ffff8880780db000)
The buggy address belongs to the physical page:
page:00000000fca63b13 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x780da
head:00000000fca63b13 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfffe0000010200(slab|head|node=0|zone=1|lastcpupid=0x3fff)
page_type: 0x1()
raw: 00fffe0000010200 ffff888100040900 ffffea000438c110 ffffea0001323210
raw: 0000000000000000 ffff8880780da000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880780d9f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8880780d9f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8880780da000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880780da080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880780da100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
general protection fault, probably for non-canonical address 0xe0b5dc4c800002ec: 0000 [#1] PREEMPT SMP KASAN
KASAN: maybe wild-memory-access in range [0x05af026400001760-0x05af026400001767]
CPU: 3 PID: 5990 Comm: syz-executor.7 Tainted: G B 6.3.0-next-20230426 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:__list_del_entry_valid+0x91/0x1b0
Code: de 48 39 c2 0f 84 80 00 00 00 48 b8 22 01 00 00 00 00 ad de 48 39 c1 74 7f 48 b8 00 00 00 00 00 fc ff df 48 89 cf 48 c1 ef 03 <80> 3c 07 00 0f 85 e7 00 00 00 4c 8b 01 49 39 f0 75 6d 48 8d 7a 08
RSP: 0018:ffffc9000d81fae0 EFLAGS: 00010213
RAX: dffffc0000000000 RBX: ffff8880780da000 RCX: 05af026400001766
RDX: ffff888046d06800 RSI: ffff8880780da000 RDI: 00b5e04c800002ec
RBP: ffff8880780da260 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff88e0008b R12: ffff8880780da008
R13: ffff8880780da260 R14: dffffc0000000000 R15: ffff88805f51c000
FS: 0000000000000000(0000) GS:ffff88811a180000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d74eb5c6a0 CR3: 000000010e5b2000 CR4: 0000000000350ee0
Call Trace:
<TASK>
hci_conn_cleanup+0x15d/0x7e0
hci_conn_del+0x2df/0x860
hci_conn_hash_flush+0x195/0x230
hci_dev_close_sync+0x5c2/0x1060
hci_unregister_dev+0x1ce/0x4a0
vhci_release+0x80/0xf0
__fput+0x27c/0xa90
task_work_run+0x168/0x260
do_exit+0xbd9/0x2b20
do_group_exit+0xd4/0x2a0
__x64_sys_exit_group+0x3e/0x50
do_syscall_64+0x39/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff463e8edcd
Code: Unable to access opcode bytes at 0x7ff463e8eda3.
RSP: 002b:00007ffde1873c18 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffde1874480 RCX: 00007ff463e8edcd
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000043
RBP: 0000000000000003 R08: 0000000000000026 R09: 00007ffde1874480
R10: 0000000000000026 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ff463eeba70 R14: 0000000000000002 R15: 00007ffde18744c0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del_entry_valid+0x91/0x1b0
Code: de 48 39 c2 0f 84 80 00 00 00 48 b8 22 01 00 00 00 00 ad de 48 39 c1 74 7f 48 b8 00 00 00 00 00 fc ff df 48 89 cf 48 c1 ef 03 <80> 3c 07 00 0f 85 e7 00 00 00 4c 8b 01 49 39 f0 75 6d 48 8d 7a 08
RSP: 0018:ffffc9000d81fae0 EFLAGS: 00010213
RAX: dffffc0000000000 RBX: ffff8880780da000 RCX: 05af026400001766
RDX: ffff888046d06800 RSI: ffff8880780da000 RDI: 00b5e04c800002ec
RBP: ffff8880780da260 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff88e0008b R12: ffff8880780da008
R13: ffff8880780da260 R14: dffffc0000000000 R15: ffff88805f51c000
FS: 0000000000000000(0000) GS:ffff88811a180000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d74eb5c6a0 CR3: 000000010e5b2000 CR4: 0000000000350ee0
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 48 39 c2 cmp %rax,%rdx
3: 0f 84 80 00 00 00 je 0x89
9: 48 b8 22 01 00 00 00 movabs $0xdead000000000122,%rax
10: 00 ad de
13: 48 39 c1 cmp %rax,%rcx
16: 74 7f je 0x97
18: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
1f: fc ff df
22: 48 89 cf mov %rcx,%rdi
25: 48 c1 ef 03 shr $0x3,%rdi
* 29: 80 3c 07 00 cmpb $0x0,(%rdi,%rax,1) <-- trapping instruction
2d: 0f 85 e7 00 00 00 jne 0x11a
33: 4c 8b 01 mov (%rcx),%r8
36: 49 39 f0 cmp %rsi,%r8
39: 75 6d jne 0xa8
3b: 48 8d 7a 08 lea 0x8(%rdx),%rdi