INFO: trying to register non-static key in hci_uart_flush (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 6d028043 Add linux-next specific files for 20190830
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=141d6cae600000
kernel config: https://syzkaller.appspot.com/x/.config?x=82a6bec43ab0cb69
dashboard link: https://syzkaller.appspot.com/bug?extid=576dfca25381fb6fbc5f
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+576dfc...@syzkaller.appspotmail.com

INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 0 PID: 31436 Comm: syz-executor.2 Not tainted 5.3.0-rc6-next-20190830
#75
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
assign_lock_key kernel/locking/lockdep.c:881 [inline]
register_lock_class+0x179e/0x1850 kernel/locking/lockdep.c:1190
__lock_acquire+0xf4/0x4a00 kernel/locking/lockdep.c:3837
lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487
percpu_down_read include/linux/percpu-rwsem.h:40 [inline]
hci_uart_flush+0x110/0x510 drivers/bluetooth/hci_ldisc.c:241
hci_uart_close drivers/bluetooth/hci_ldisc.c:267 [inline]
hci_uart_tty_close+0x8e/0x280 drivers/bluetooth/hci_ldisc.c:534
tty_ldisc_close.isra.0+0x119/0x1a0 drivers/tty/tty_ldisc.c:494
tty_ldisc_kill+0x9c/0x160 drivers/tty/tty_ldisc.c:642
tty_ldisc_release+0xe9/0x2b0 drivers/tty/tty_ldisc.c:814
tty_release_struct+0x1b/0x50 drivers/tty/tty_io.c:1612
tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1785
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
get_signal+0x2078/0x2500 kernel/signal.c:2528
do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5b36328c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000459879
RDX: 0000000000000002 RSI: 00000000400455c8 RDI: 0000000000000003
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5b363296d4
R13: 00000000004c2586 R14: 00000000004d5ae8 R15: 00000000ffffffff
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 31436 Comm: syz-executor.2 Not tainted 5.3.0-rc6-next-20190830
#75
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__wake_up_common+0xdf/0x610 kernel/sched/wait.c:86
Code: 05 00 00 4c 8b 43 38 49 83 e8 18 49 8d 78 18 48 39 7d d0 0f 84 64 02
00 00 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f
85 0d 05 00 00 49 8b 40 18 89 55 b0 31 db 49 bc 00
RSP: 0018:ffff8880979bf818 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff8880a7ff48b8 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 1ffffffff138b536 RDI: 0000000000000000
RBP: ffff8880979bf870 R08: ffffffffffffffe8 R09: 0000000000000000
R10: ffffed1012f37efe R11: 0000000000000003 R12: ffff8880a7ff4900
R13: ffff8880a7ff48b0 R14: 0000000000000000 R15: ffff8880a7ff48b8
FS: 00007f5b36329700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000000a81a2000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__wake_up_locked+0x11/0x20 kernel/sched/wait.c:151
rcu_sync_func+0x16f/0x200 kernel/rcu/sync.c:87
rcu_sync_enter+0x158/0x310 kernel/rcu/sync.c:150
percpu_down_write+0x61/0x440 kernel/locking/percpu-rwsem.c:146
hci_uart_tty_close+0x154/0x280 drivers/bluetooth/hci_ldisc.c:537
tty_ldisc_close.isra.0+0x119/0x1a0 drivers/tty/tty_ldisc.c:494
tty_ldisc_kill+0x9c/0x160 drivers/tty/tty_ldisc.c:642
tty_ldisc_release+0xe9/0x2b0 drivers/tty/tty_ldisc.c:814
tty_release_struct+0x1b/0x50 drivers/tty/tty_io.c:1612
tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1785
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
get_signal+0x2078/0x2500 kernel/signal.c:2528
do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5b36328c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000459879
RDX: 0000000000000002 RSI: 00000000400455c8 RDI: 0000000000000003
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5b363296d4
R13: 00000000004c2586 R14: 00000000004d5ae8 R15: 00000000ffffffff
Modules linked in:
---[ end trace d1da9c36c5e69966 ]---
RIP: 0010:__wake_up_common+0xdf/0x610 kernel/sched/wait.c:86
Code: 05 00 00 4c 8b 43 38 49 83 e8 18 49 8d 78 18 48 39 7d d0 0f 84 64 02
00 00 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f
85 0d 05 00 00 49 8b 40 18 89 55 b0 31 db 49 bc 00
RSP: 0018:ffff8880979bf818 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff8880a7ff48b8 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 1ffffffff138b536 RDI: 0000000000000000
RBP: ffff8880979bf870 R08: ffffffffffffffe8 R09: 0000000000000000
R10: ffffed1012f37efe R11: 0000000000000003 R12: ffff8880a7ff4900
R13: ffff8880a7ff48b0 R14: 0000000000000000 R15: ffff8880a7ff48b8
FS: 00007f5b36329700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000000a81a2000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
This bug 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 bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: e94f8ccd Merge tag 'smack-for-5.4-rc1' of git://github.com..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16713de9600000
kernel config: https://syzkaller.appspot.com/x/.config?x=df38eec565aab18d

dashboard link: https://syzkaller.appspot.com/bug?extid=576dfca25381fb6fbc5f
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12881a9d600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+576dfc...@syzkaller.appspotmail.com

INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.

CPU: 0 PID: 9385 Comm: syz-executor.3 Not tainted 5.3.0+ #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
assign_lock_key kernel/locking/lockdep.c:881 [inline]
register_lock_class+0x179e/0x1850 kernel/locking/lockdep.c:1190

__lock_acquire+0xf4/0x4e70 kernel/locking/lockdep.c:3837

lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487
percpu_down_read include/linux/percpu-rwsem.h:40 [inline]
hci_uart_flush+0x110/0x510 drivers/bluetooth/hci_ldisc.c:241
hci_uart_close drivers/bluetooth/hci_ldisc.c:267 [inline]
hci_uart_tty_close+0x8e/0x280 drivers/bluetooth/hci_ldisc.c:534

tty_ldisc_close.isra.0+0x119/0x190 drivers/tty/tty_ldisc.c:494

tty_ldisc_kill+0x9c/0x160 drivers/tty/tty_ldisc.c:642
tty_ldisc_release+0xe9/0x2b0 drivers/tty/tty_ldisc.c:814
tty_release_struct+0x1b/0x50 drivers/tty/tty_io.c:1612
tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1785
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113

exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x92f/0x2e50 kernel/exit.c:879
do_group_exit+0x135/0x360 kernel/exit.c:983
get_signal+0x47c/0x2500 kernel/signal.c:2734

do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300
entry_SYSCALL_64_after_hwframe+0x49/0xbe

RIP: 0033:0x459a09
Code: Bad RIP value.
RSP: 002b:00007fe8f55a0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000459a09
RDX: 0000000000000002 RSI: 00000000400455c8 RDI: 0000000000000006
RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8f55a16d4
R13: 00000000004c26f7 R14: 00000000004d5df8 R15: 00000000ffffffff

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN

CPU: 0 PID: 9385 Comm: syz-executor.3 Not tainted 5.3.0+ #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__wake_up_common+0xdf/0x610 kernel/sched/wait.c:86
Code: 05 00 00 4c 8b 43 38 49 83 e8 18 49 8d 78 18 48 39 7d d0 0f 84 64 02
00 00 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f

85 0b 05 00 00 49 8b 40 18 89 55 b0 31 db 49 bc 00
RSP: 0018:ffff888097617698 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff88809612eb38 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 1ffffffff138dcf6 RDI: 0000000000000000
RBP: ffff8880976176f0 R08: ffffffffffffffe8 R09: 0000000000000000
R10: ffffed1012ec2ece R11: 0000000000000003 R12: ffff88809612eb80
R13: ffff88809612eb30 R14: 0000000000000000 R15: ffff88809612eb38
FS: 00007fe8f55a1700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00000000004599df CR3: 000000008ff2c000 CR4: 00000000001406f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__wake_up_locked+0x11/0x20 kernel/sched/wait.c:151
rcu_sync_func+0x16f/0x200 kernel/rcu/sync.c:87
rcu_sync_enter+0x158/0x310 kernel/rcu/sync.c:150

percpu_down_write+0x61/0x437 kernel/locking/percpu-rwsem.c:146
hci_uart_tty_close+0x154/0x280 drivers/bluetooth/hci_ldisc.c:537
tty_ldisc_close.isra.0+0x119/0x190 drivers/tty/tty_ldisc.c:494

tty_ldisc_kill+0x9c/0x160 drivers/tty/tty_ldisc.c:642
tty_ldisc_release+0xe9/0x2b0 drivers/tty/tty_ldisc.c:814
tty_release_struct+0x1b/0x50 drivers/tty/tty_io.c:1612
tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1785
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113

exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x92f/0x2e50 kernel/exit.c:879
do_group_exit+0x135/0x360 kernel/exit.c:983
get_signal+0x47c/0x2500 kernel/signal.c:2734

do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300
entry_SYSCALL_64_after_hwframe+0x49/0xbe

RIP: 0033:0x459a09

Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00

RSP: 002b:00007fe8f55a0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000459a09
RDX: 0000000000000002 RSI: 00000000400455c8 RDI: 0000000000000006
RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8f55a16d4
R13: 00000000004c26f7 R14: 00000000004d5df8 R15: 00000000ffffffff
Modules linked in:
---[ end trace cf75381aeb7c112c ]---

RIP: 0010:__wake_up_common+0xdf/0x610 kernel/sched/wait.c:86
Code: 05 00 00 4c 8b 43 38 49 83 e8 18 49 8d 78 18 48 39 7d d0 0f 84 64 02
00 00 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f

85 0b 05 00 00 49 8b 40 18 89 55 b0 31 db 49 bc 00
RSP: 0018:ffff888097617698 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff88809612eb38 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 1ffffffff138dcf6 RDI: 0000000000000000
RBP: ffff8880976176f0 R08: ffffffffffffffe8 R09: 0000000000000000
R10: ffffed1012ec2ece R11: 0000000000000003 R12: ffff88809612eb80
R13: ffff88809612eb30 R14: 0000000000000000 R15: ffff88809612eb38
FS: 00007fe8f55a1700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00000000004599df CR3: 000000008ff2c000 CR4: 00000000001406f0

[Tetsuo Handa]

syzbot is reporting NULL pointer dereference at hci_uart_tty_close() [1],
for rcu_sync_enter() is called without rcu_sync_init() due to
hci_uart_tty_open() ignoring percpu_init_rwsem() failure.

While we are at it, fix that hci_uart_register_device() ignores
percpu_init_rwsem() failure and hci_uart_unregister_device() does not
call percpu_free_rwsem().

Link: https://syzkaller.appspot.com/bug?extid=576dfca25381fb6fbc5f [1]
Reported-by: syzbot <syzbot+576dfc...@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin...@I-love.SAKURA.ne.jp>
Fixes: 67d2f8781b9f00d1 ("Bluetooth: hci_ldisc: Allow sleeping while proto locks are held.")
Fixes: d73e172816652772 ("Bluetooth: hci_serdev: Init hci_uart proto_lock to avoid oops")
---
drivers/bluetooth/hci_ldisc.c | 7 +++++--
drivers/bluetooth/hci_serdev.c | 10 +++++++---
2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index f537673ede17..865112e96ff9 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -493,6 +493,11 @@ static int hci_uart_tty_open(struct tty_struct *tty)
BT_ERR("Can't allocate control structure");
return -ENFILE;
}
+ if (percpu_init_rwsem(&hu->proto_lock)) {
+ BT_ERR("Can't allocate semaphore structure");
+ kfree(hu);
+ return -ENOMEM;
+ }

tty->disc_data = hu;
hu->tty = tty;
@@ -505,8 +510,6 @@ static int hci_uart_tty_open(struct tty_struct *tty)
INIT_WORK(&hu->init_ready, hci_uart_init_work);
INIT_WORK(&hu->write_work, hci_uart_write_work);

- percpu_init_rwsem(&hu->proto_lock);
-
/* Flush any pending characters in the driver */
tty_driver_flush_buffer(tty);

diff --git a/drivers/bluetooth/hci_serdev.c b/drivers/bluetooth/hci_serdev.c
index c0e5f42ec6b7..f16fd79bc02b 100644
--- a/drivers/bluetooth/hci_serdev.c
+++ b/drivers/bluetooth/hci_serdev.c
@@ -310,11 +310,12 @@ int hci_uart_register_device(struct hci_uart *hu,

serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops);

+ if (percpu_init_rwsem(&hu->proto_lock))
+ return -ENOMEM;
+
err = serdev_device_open(hu->serdev);
if (err)
- return err;
-
- percpu_init_rwsem(&hu->proto_lock);
+ goto err_rwsem;

err = p->open(hu);
if (err)
@@ -389,6 +390,8 @@ int hci_uart_register_device(struct hci_uart *hu,
p->close(hu);
err_open:
serdev_device_close(hu->serdev);
+err_rwsem:
+ percpu_free_rwsem(&hu->proto_lock);
return err;
}
EXPORT_SYMBOL_GPL(hci_uart_register_device);
@@ -410,5 +413,6 @@ void hci_uart_unregister_device(struct hci_uart *hu)
clear_bit(HCI_UART_PROTO_READY, &hu->flags);
serdev_device_close(hu->serdev);
}
+ percpu_free_rwsem(&hu->proto_lock);
}
EXPORT_SYMBOL_GPL(hci_uart_unregister_device);
--
2.18.4

[patchwork-b...@kernel.org]

Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <luiz.vo...@intel.com>:

On Mon, 29 Aug 2022 23:58:12 +0900 you wrote:
> syzbot is reporting NULL pointer dereference at hci_uart_tty_close() [1],
> for rcu_sync_enter() is called without rcu_sync_init() due to
> hci_uart_tty_open() ignoring percpu_init_rwsem() failure.
>
> While we are at it, fix that hci_uart_register_device() ignores
> percpu_init_rwsem() failure and hci_uart_unregister_device() does not
> call percpu_free_rwsem().
>

> [...]

Here is the summary with links:
- Bluetooth: hci_{ldisc,serdev}: check percpu_init_rwsem() failure
https://git.kernel.org/bluetooth/bluetooth-next/c/3124d320c22f

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
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