[syzbot] KASAN: use-after-free Read in mgmt_pending_remove

From: syzbot
Date: Wed Aug 17 2022 - 06:42:41 EST


Hello,

syzbot found the following issue on:

HEAD commit: 40b4ac880e21 net: lan966x: fix checking for return value o..
git tree: net
console+strace: https://syzkaller.appspot.com/x/log.txt?x=14d10915080000
kernel config: https://syzkaller.appspot.com/x/.config?x=924833c12349a8c0
dashboard link: https://syzkaller.appspot.com/bug?extid=915a8416bf15895b8e07
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=115e3d15080000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12917dc3080000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+915a8416bf15895b8e07@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: use-after-free in __list_del_entry_valid+0xde/0x110 lib/list_debug.c:46
Read of size 8 at addr ffff888020a29408 by task syz-executor378/3646

CPU: 1 PID: 3646 Comm: syz-executor378 Not tainted 5.19.0-syzkaller-13938-g40b4ac880e21 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:317 [inline]
print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
__list_del_entry_valid+0xde/0x110 lib/list_debug.c:46
__list_del_entry include/linux/list.h:134 [inline]
list_del include/linux/list.h:148 [inline]
mgmt_pending_remove+0x1a/0x160 net/bluetooth/mgmt_util.c:314
remove_adv_monitor+0x1b9/0x1c0 net/bluetooth/mgmt.c:5057
hci_mgmt_cmd net/bluetooth/hci_sock.c:1619 [inline]
hci_sock_sendmsg+0x1dee/0x2490 net/bluetooth/hci_sock.c:1739
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
sock_write_iter+0x291/0x3d0 net/socket.c:1108
call_write_iter include/linux/fs.h:2192 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x1e8/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f90195b9779
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffc4302508 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f90195b9779
RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007fffc4302570 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000011 R14: 00007fffc4302580 R15: 0000000000000000
</TASK>

Allocated by task 3646:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:437 [inline]
____kasan_kmalloc mm/kasan/common.c:516 [inline]
____kasan_kmalloc mm/kasan/common.c:475 [inline]
__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525
kmalloc include/linux/slab.h:600 [inline]
kzalloc include/linux/slab.h:733 [inline]
mgmt_pending_new+0x57/0x290 net/bluetooth/mgmt_util.c:269
mgmt_pending_add+0x34/0x160 net/bluetooth/mgmt_util.c:296
remove_adv_monitor+0x120/0x1c0 net/bluetooth/mgmt.c:5040
hci_mgmt_cmd net/bluetooth/hci_sock.c:1619 [inline]
hci_sock_sendmsg+0x1dee/0x2490 net/bluetooth/hci_sock.c:1739
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
sock_write_iter+0x291/0x3d0 net/socket.c:1108
call_write_iter include/linux/fs.h:2192 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x1e8/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 3646:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:45
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:367 [inline]
____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329
kasan_slab_free include/linux/kasan.h:200 [inline]
slab_free_hook mm/slub.c:1754 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1780
slab_free mm/slub.c:3534 [inline]
kfree+0xe2/0x580 mm/slub.c:4562
remove_adv_monitor+0x18b/0x1c0 net/bluetooth/mgmt.c:5050
hci_mgmt_cmd net/bluetooth/hci_sock.c:1619 [inline]
hci_sock_sendmsg+0x1dee/0x2490 net/bluetooth/hci_sock.c:1739
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
sock_write_iter+0x291/0x3d0 net/socket.c:1108
call_write_iter include/linux/fs.h:2192 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x1e8/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff888020a29400
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 8 bytes inside of
96-byte region [ffff888020a29400, ffff888020a29460)

The buggy address belongs to the physical page:
page:ffffea0000828a40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20a29
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea0000953600 dead000000000004 ffff888011841780
raw: 0000000000000000 0000000080200020 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 0x12c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY), pid 2976, tgid 2976 (udevd), ts 23016454578, free_ts 23008667437
prep_new_page mm/page_alloc.c:2532 [inline]
get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283
__alloc_pages+0x1c7/0x510 mm/page_alloc.c:5515
alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270
alloc_slab_page mm/slub.c:1824 [inline]
allocate_slab+0x27e/0x3d0 mm/slub.c:1969
new_slab mm/slub.c:2029 [inline]
___slab_alloc+0x7f1/0xe10 mm/slub.c:3031
__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118
slab_alloc_node mm/slub.c:3209 [inline]
slab_alloc mm/slub.c:3251 [inline]
__kmalloc+0x32b/0x340 mm/slub.c:4420
kmalloc include/linux/slab.h:605 [inline]
kzalloc include/linux/slab.h:733 [inline]
tomoyo_encode2.part.0+0xe9/0x3a0 security/tomoyo/realpath.c:45
tomoyo_encode2 security/tomoyo/realpath.c:31 [inline]
tomoyo_encode+0x28/0x50 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x186/0x620 security/tomoyo/realpath.c:288
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822
security_inode_getattr+0xcf/0x140 security/security.c:1345
vfs_getattr fs/stat.c:157 [inline]
vfs_statx+0x16a/0x390 fs/stat.c:232
vfs_fstatat+0x8c/0xb0 fs/stat.c:255
__do_sys_newfstatat+0x91/0x110 fs/stat.c:425
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1449 [inline]
free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499
free_unref_page_prepare mm/page_alloc.c:3380 [inline]
free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447
kasan_slab_alloc include/linux/kasan.h:224 [inline]
slab_post_alloc_hook mm/slab.h:727 [inline]
slab_alloc_node mm/slub.c:3243 [inline]
slab_alloc mm/slub.c:3251 [inline]
__kmem_cache_alloc_lru mm/slub.c:3258 [inline]
kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3268
getname_flags.part.0+0x50/0x4f0 fs/namei.c:139
getname_flags include/linux/audit.h:321 [inline]
getname+0x8e/0xd0 fs/namei.c:218
do_sys_openat2+0xf5/0x4c0 fs/open.c:1305
do_sys_open fs/open.c:1327 [inline]
__do_sys_openat fs/open.c:1343 [inline]
__se_sys_openat fs/open.c:1338 [inline]
__x64_sys_openat+0x13f/0x1f0 fs/open.c:1338
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
ffff888020a29300: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
ffff888020a29380: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
>ffff888020a29400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff888020a29480: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
ffff888020a29500: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
==================================================================


---
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