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| author | Pavel Skripkin <paskripkin@gmail.com> | 2022-01-13 16:27:04 +0300 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2022-01-22 01:46:48 +0300 |
| commit | 9d7cbe2b9cf5f650067df4f402fdd799d4bbb4e1 (patch) | |
| tree | 1f055ae3e30424c462aed9361caf1cce289d2ce6 /drivers/bluetooth/hci_serdev.c | |
| parent | a86974f75e8806bc357a9be02f9bde083f40b4ae (diff) | |
| download | linux-9d7cbe2b9cf5f650067df4f402fdd799d4bbb4e1.tar.xz | |
Bluetooth: hci_serdev: call init_rwsem() before p->open()
kvartet reported, that hci_uart_tx_wakeup() uses uninitialized rwsem.
The problem was in wrong place for percpu_init_rwsem() call.
hci_uart_proto::open() may register a timer whose callback may call
hci_uart_tx_wakeup(). There is a chance, that hci_uart_register_device()
thread won't be fast enough to call percpu_init_rwsem().
Fix it my moving percpu_init_rwsem() call before p->open().
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 2 PID: 18524 Comm: syz-executor.5 Not tainted 5.16.0-rc6 #9
...
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
assign_lock_key kernel/locking/lockdep.c:951 [inline]
register_lock_class+0x148d/0x1950 kernel/locking/lockdep.c:1263
__lock_acquire+0x106/0x57e0 kernel/locking/lockdep.c:4906
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5602
percpu_down_read_trylock include/linux/percpu-rwsem.h:92 [inline]
hci_uart_tx_wakeup+0x12e/0x490 drivers/bluetooth/hci_ldisc.c:124
h5_timed_event+0x32f/0x6a0 drivers/bluetooth/hci_h5.c:188
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
Fixes: d73e17281665 ("Bluetooth: hci_serdev: Init hci_uart proto_lock to avoid oops")
Reported-by: Yiru Xu <xyru1999@gmail.com>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'drivers/bluetooth/hci_serdev.c')
| -rw-r--r-- | drivers/bluetooth/hci_serdev.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/bluetooth/hci_serdev.c b/drivers/bluetooth/hci_serdev.c index 3b00d82d36cf..4cda890ce647 100644 --- a/drivers/bluetooth/hci_serdev.c +++ b/drivers/bluetooth/hci_serdev.c @@ -305,6 +305,8 @@ int hci_uart_register_device(struct hci_uart *hu, if (err) return err; + percpu_init_rwsem(&hu->proto_lock); + err = p->open(hu); if (err) goto err_open; @@ -327,7 +329,6 @@ int hci_uart_register_device(struct hci_uart *hu, INIT_WORK(&hu->init_ready, hci_uart_init_work); INIT_WORK(&hu->write_work, hci_uart_write_work); - percpu_init_rwsem(&hu->proto_lock); /* Only when vendor specific setup callback is provided, consider * the manufacturer information valid. This avoids filling in the |