diff options
| author | Matthias Kaehlcke <mka@chromium.org> | 2019-01-02 16:11:20 -0800 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2019-01-22 09:51:20 +0100 |
| commit | c4f5627f7eeecde1bb6b646d8c0907b96dc2b2a6 (patch) | |
| tree | 3caa470f040d4ce977c331a8367f2f70db561c79 /net/bluetooth/rfcomm | |
| parent | 8c57983bf7a7987f957830614b1645bd6943f5af (diff) | |
| download | linux-c4f5627f7eeecde1bb6b646d8c0907b96dc2b2a6.tar.bz2 | |
Bluetooth: Fix locking in bt_accept_enqueue() for BH context
With commit e16337622016 ("Bluetooth: Handle bt_accept_enqueue() socket
atomically") lock_sock[_nested]() is used to acquire the socket lock
before manipulating the socket. lock_sock[_nested]() may block, which
is problematic since bt_accept_enqueue() can be called in bottom half
context (e.g. from rfcomm_connect_ind()):
[<ffffff80080d81ec>] __might_sleep+0x4c/0x80
[<ffffff800876c7b0>] lock_sock_nested+0x24/0x58
[<ffffff8000d7c27c>] bt_accept_enqueue+0x48/0xd4 [bluetooth]
[<ffffff8000e67d8c>] rfcomm_connect_ind+0x190/0x218 [rfcomm]
Add a parameter to bt_accept_enqueue() to indicate whether the
function is called from BH context, and acquire the socket lock
with bh_lock_sock_nested() if that's the case.
Also adapt all callers of bt_accept_enqueue() to pass the new
parameter:
- l2cap_sock_new_connection_cb()
- uses lock_sock() to lock the parent socket => process context
- rfcomm_connect_ind()
- acquires the parent socket lock with bh_lock_sock() => BH
context
- __sco_chan_add()
- called from sco_chan_add(), which is called from sco_connect().
parent is NULL, hence bt_accept_enqueue() isn't called in this
code path and we can ignore it
- also called from sco_conn_ready(). uses bh_lock_sock() to acquire
the parent lock => BH context
Fixes: e16337622016 ("Bluetooth: Handle bt_accept_enqueue() socket atomically")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
Diffstat (limited to 'net/bluetooth/rfcomm')
| -rw-r--r-- | net/bluetooth/rfcomm/sock.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c index aa0db1d1bd9b..b1f49fcc0478 100644 --- a/net/bluetooth/rfcomm/sock.c +++ b/net/bluetooth/rfcomm/sock.c @@ -988,7 +988,7 @@ int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc * rfcomm_pi(sk)->channel = channel; sk->sk_state = BT_CONFIG; - bt_accept_enqueue(parent, sk); + bt_accept_enqueue(parent, sk, true); /* Accept connection and return socket DLC */ *d = rfcomm_pi(sk)->dlc; |