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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 75887e88 Merge branch '40GbE' of git://git.kernel.org/pub/..
git tree: net
console output: https://syzkaller.appspot.com/x/log.txt?x=12d6bb06d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=5adab0bdee099d7a
dashboard link: https://syzkaller.appspot.com/bug?extid=8b7c5fc0cfb74afee8d1
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15c2db21d00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1091d4bed00000

The issue was bisected to:

commit 997acaf6b4b59c6a9c259740312a69ea549cc684
Author: Mark Rutland <mark.r...@arm.com>
Date: Mon Jan 11 15:37:07 2021 +0000

lockdep: report broken irq restoration

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12636d06d00000
final oops: https://syzkaller.appspot.com/x/report.txt?x=11636d06d00000
console output: https://syzkaller.appspot.com/x/log.txt?x=16636d06d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8b7c5f...@syzkaller.appspotmail.com
Fixes: 997acaf6b4b5 ("lockdep: report broken irq restoration")

==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x3e6f/0x54c0 kernel/locking/lockdep.c:4770
Read of size 8 at addr ffff888144614468 by task syz-executor242/8422

CPU: 0 PID: 8422 Comm: syz-executor242 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x141/0x1d7 lib/dump_stack.c:120
print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
__kasan_report mm/kasan/report.c:399 [inline]
kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
__lock_acquire+0x3e6f/0x54c0 kernel/locking/lockdep.c:4770
lock_acquire kernel/locking/lockdep.c:5510 [inline]
lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5475
__raw_write_lock include/linux/rwlock_api_smp.h:210 [inline]
_raw_write_lock+0x2a/0x40 kernel/locking/spinlock.c:295
nfc_llcp_sock_unlink+0x1d/0x1c0 net/nfc/llcp_core.c:32
llcp_sock_release+0x286/0x580 net/nfc/llcp_sock.c:640
__sock_release+0xcd/0x280 net/socket.c:599
sock_close+0x18/0x20 net/socket.c:1258
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:140
exit_task_work include/linux/task_work.h:30 [inline]
do_exit+0xbfc/0x2a60 kernel/exit.c:825
do_group_exit+0x125/0x310 kernel/exit.c:922
__do_sys_exit_group kernel/exit.c:933 [inline]
__se_sys_exit_group kernel/exit.c:931 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43db99
Code: Unable to access opcode bytes at RIP 0x43db6f.
RSP: 002b:00007ffdd4d753e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00000000004ae230 RCX: 000000000043db99
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000400488
R10: 0000000000400488 R11: 0000000000000246 R12: 00000000004ae230
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001

Allocated by task 1:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:427 [inline]
____kasan_kmalloc mm/kasan/common.c:506 [inline]
____kasan_kmalloc mm/kasan/common.c:465 [inline]
__kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
kmalloc include/linux/slab.h:554 [inline]
kzalloc include/linux/slab.h:684 [inline]
nfc_llcp_register_device+0x45/0x9d0 net/nfc/llcp_core.c:1572
nfc_register_device+0x6d/0x360 net/nfc/core.c:1124
nfcsim_device_new+0x345/0x5c1 drivers/nfc/nfcsim.c:408
nfcsim_init+0x71/0x14d drivers/nfc/nfcsim.c:455
do_one_initcall+0x103/0x650 init/main.c:1226
do_initcall_level init/main.c:1299 [inline]
do_initcalls init/main.c:1315 [inline]
do_basic_setup init/main.c:1335 [inline]
kernel_init_freeable+0x63e/0x6c2 init/main.c:1537
kernel_init+0xd/0x1b8 init/main.c:1424
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Freed by task 8422:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
____kasan_slab_free mm/kasan/common.c:360 [inline]
____kasan_slab_free mm/kasan/common.c:325 [inline]
__kasan_slab_free+0xf5/0x130 mm/kasan/common.c:367
kasan_slab_free include/linux/kasan.h:199 [inline]
slab_free_hook mm/slub.c:1562 [inline]
slab_free_freelist_hook+0x92/0x210 mm/slub.c:1600
slab_free mm/slub.c:3161 [inline]
kfree+0xe5/0x7f0 mm/slub.c:4213
local_release net/nfc/llcp_core.c:175 [inline]
kref_put include/linux/kref.h:65 [inline]
nfc_llcp_local_put net/nfc/llcp_core.c:183 [inline]
nfc_llcp_local_put+0x194/0x200 net/nfc/llcp_core.c:178
llcp_sock_destruct+0x81/0x150 net/nfc/llcp_sock.c:950
__sk_destruct+0x4b/0x900 net/core/sock.c:1795
sk_destruct+0xbd/0xe0 net/core/sock.c:1839
__sk_free+0xef/0x3d0 net/core/sock.c:1850
sk_free+0x78/0xa0 net/core/sock.c:1861
sock_put include/net/sock.h:1803 [inline]
llcp_sock_release+0x3c9/0x580 net/nfc/llcp_sock.c:644
__sock_release+0xcd/0x280 net/socket.c:599
sock_close+0x18/0x20 net/socket.c:1258
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:140
exit_task_work include/linux/task_work.h:30 [inline]
do_exit+0xbfc/0x2a60 kernel/exit.c:825
do_group_exit+0x125/0x310 kernel/exit.c:922
__do_sys_exit_group kernel/exit.c:933 [inline]
__se_sys_exit_group kernel/exit.c:931 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888144614000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1128 bytes inside of
2048-byte region [ffff888144614000, ffff888144614800)
The buggy address belongs to the page:
page:ffffea0005118400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888144616000 pfn:0x144610
head:ffffea0005118400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x57ff00000010200(slab|head)
raw: 057ff00000010200 ffffea00050f2008 ffffea00050f1e08 ffff888010842000
raw: ffff888144616000 0000000000080006 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff888144614300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888144614380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888144614400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888144614480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888144614500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: use-after-free Read in nfc_llcp_sock_unlink

==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x3e6f/0x54c0 kernel/locking/lockdep.c:4770

Read of size 8 at addr ffff888144303468 by task syz-executor.0/10162

CPU: 0 PID: 10162 Comm: syz-executor.0 Not tainted 5.12.0-rc4-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x141/0x1d7 lib/dump_stack.c:120
print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
__kasan_report mm/kasan/report.c:399 [inline]
kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
__lock_acquire+0x3e6f/0x54c0 kernel/locking/lockdep.c:4770
lock_acquire kernel/locking/lockdep.c:5510 [inline]
lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5475
__raw_write_lock include/linux/rwlock_api_smp.h:210 [inline]
_raw_write_lock+0x2a/0x40 kernel/locking/spinlock.c:295
nfc_llcp_sock_unlink+0x1d/0x1c0 net/nfc/llcp_core.c:32

llcp_sock_release+0x297/0x5b0 net/nfc/llcp_sock.c:643

__sock_release+0xcd/0x280 net/socket.c:599
sock_close+0x18/0x20 net/socket.c:1258
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:140

tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:208
__syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x41926b
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
RSP: 002b:00007fff384ce5d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 000000000041926b
RDX: ffffffffffffffbc RSI: 0000000000000001 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b32a20070
R10: 00007fff384ce6c0 R11: 0000000000000293 R12: 0000000000019bbe
R13: 00000000000003e8 R14: 000000000056bf60 R15: 0000000000019ba9

Allocated by task 1:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:427 [inline]
____kasan_kmalloc mm/kasan/common.c:506 [inline]
____kasan_kmalloc mm/kasan/common.c:465 [inline]
__kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
kmalloc include/linux/slab.h:554 [inline]
kzalloc include/linux/slab.h:684 [inline]
nfc_llcp_register_device+0x45/0x9d0 net/nfc/llcp_core.c:1572
nfc_register_device+0x6d/0x360 net/nfc/core.c:1124
nfcsim_device_new+0x345/0x5c1 drivers/nfc/nfcsim.c:408
nfcsim_init+0x71/0x14d drivers/nfc/nfcsim.c:455
do_one_initcall+0x103/0x650 init/main.c:1226
do_initcall_level init/main.c:1299 [inline]
do_initcalls init/main.c:1315 [inline]
do_basic_setup init/main.c:1335 [inline]
kernel_init_freeable+0x63e/0x6c2 init/main.c:1537
kernel_init+0xd/0x1b8 init/main.c:1424
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Freed by task 10162:

kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
____kasan_slab_free mm/kasan/common.c:360 [inline]
____kasan_slab_free mm/kasan/common.c:325 [inline]
__kasan_slab_free+0xf5/0x130 mm/kasan/common.c:367
kasan_slab_free include/linux/kasan.h:199 [inline]
slab_free_hook mm/slub.c:1562 [inline]
slab_free_freelist_hook+0x92/0x210 mm/slub.c:1600
slab_free mm/slub.c:3161 [inline]
kfree+0xe5/0x7f0 mm/slub.c:4213
local_release net/nfc/llcp_core.c:175 [inline]
kref_put include/linux/kref.h:65 [inline]
nfc_llcp_local_put net/nfc/llcp_core.c:183 [inline]
nfc_llcp_local_put+0x194/0x200 net/nfc/llcp_core.c:178

llcp_sock_destruct+0x81/0x150 net/nfc/llcp_sock.c:955

__sk_destruct+0x4b/0x900 net/core/sock.c:1795
sk_destruct+0xbd/0xe0 net/core/sock.c:1839
__sk_free+0xef/0x3d0 net/core/sock.c:1850
sk_free+0x78/0xa0 net/core/sock.c:1861

sock_put include/net/sock.h:1807 [inline]
llcp_sock_release+0x3ea/0x5b0 net/nfc/llcp_sock.c:647

__sock_release+0xcd/0x280 net/socket.c:599
sock_close+0x18/0x20 net/socket.c:1258
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:140

tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:208
__syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888144303000

which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1128 bytes inside of

2048-byte region [ffff888144303000, ffff888144303800)

The buggy address belongs to the page:

page:ffffea000510c000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x144300
head:ffffea000510c000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x57ff00000010200(slab|head)
raw: 057ff00000010200 dead000000000100 dead000000000122 ffff888010042000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000

page dumped because: kasan: bad access detected

Memory state around the buggy address:

ffff888144303300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888144303380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888144303400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888144303480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888144303500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


Tested on:

commit: a14d273b net: macb: restore cmp registers on resume path
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=140c88fcd00000
kernel config: https://syzkaller.appspot.com/x/.config?x=4b6433fa3370faed
dashboard link: https://syzkaller.appspot.com/bug?extid=8b7c5fc0cfb74afee8d1
compiler:
patch: https://syzkaller.appspot.com/x/patch.diff?x=16b488fcd00000

[syzbot]

syzbot suspects this issue was fixed by commit:

commit f567d6ef8606fb427636e824c867229ecb5aefab
Author: Maxim Mikityanskiy <maxt...@gmail.com>
Date: Sun Feb 7 14:47:40 2021 +0000

HID: plantronics: Workaround for double volume key presses

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14e41588300000
start commit: bbd6f0a9 bnxt_en: Fix RX consumer index logic in the error..
git tree: net
kernel config: https://syzkaller.appspot.com/x/.config?x=339c2ecce8fdd1d0
dashboard link: https://syzkaller.appspot.com/bug?extid=8b7c5fc0cfb74afee8d1
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1712a893d00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1298b469d00000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: HID: plantronics: Workaround for double volume key presses

[Maxim Mikityanskiy]

On Mon, Jun 7, 2021 at 2:27 AM syzbot
<syzbot+8b7c5f...@syzkaller.appspotmail.com> wrote:
>
> syzbot suspects this issue was fixed by commit:
>
> commit f567d6ef8606fb427636e824c867229ecb5aefab
> Author: Maxim Mikityanskiy <maxt...@gmail.com>
> Date: Sun Feb 7 14:47:40 2021 +0000
>
> HID: plantronics: Workaround for double volume key presses

Dear syzbot,

I highly doubt my commit could fix any use-after-free bug in NFC. It's
not related to NFC, and it's not a bugfix. Probably the repro isn't
100% stable, so the bisect results are invalid.

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.