From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> commit ba8f5289f706aed94cc95b15cc5b89e22062f61f upstream. l2cap_le_flowctl_init was reseting the tx_credits which works only for outgoing connection since that set the tx_credits on the response, for incoming connections that was not the case which leaves the channel without any credits causing it to be suspended. Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # 4.20+ Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/bluetooth/l2cap_core.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -510,12 +510,12 @@ void l2cap_chan_set_defaults(struct l2ca } EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults); -static void l2cap_le_flowctl_init(struct l2cap_chan *chan) +static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits) { chan->sdu = NULL; chan->sdu_last_frag = NULL; chan->sdu_len = 0; - chan->tx_credits = 0; + chan->tx_credits = tx_credits; /* Derive MPS from connection MTU to stop HCI fragmentation */ chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE); /* Give enough credits for a full packet */ @@ -1281,7 +1281,7 @@ static void l2cap_le_connect(struct l2ca if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags)) return; - l2cap_le_flowctl_init(chan); + l2cap_le_flowctl_init(chan, 0); req.psm = chan->psm; req.scid = cpu_to_le16(chan->scid); @@ -5532,11 +5532,10 @@ static int l2cap_le_connect_req(struct l chan->dcid = scid; chan->omtu = mtu; chan->remote_mps = mps; - chan->tx_credits = __le16_to_cpu(req->credits); __l2cap_chan_add(conn, chan); - l2cap_le_flowctl_init(chan); + l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits)); dcid = chan->scid; credits = chan->rx_credits;