Bluetooth: Fix ACL MTU issue

ERTM and Streaming Modes was having problems when the ACL MTU is lower
than MPS. The 'minus 10' is to take in account the header and fcs
lenghts.

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 401011a53c73b898f144c2f3451e5e0c50e8ba30..99cf1772b481896fa945741985df54bb0856aacc 100644 (file)
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -2267,6 +2267,8 @@ done:
                rfc.retrans_timeout = 0;
                rfc.monitor_timeout = 0;
                rfc.max_pdu_size    = cpu_to_le16(L2CAP_DEFAULT_MAX_PDU_SIZE);
+               if (L2CAP_DEFAULT_MAX_PDU_SIZE > pi->conn->mtu - 10)
+                       rfc.max_pdu_size = pi->conn->mtu - 10;
 
                l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
                                        sizeof(rfc), (unsigned long) &rfc);
@@ -2288,6 +2290,8 @@ done:
                rfc.retrans_timeout = 0;
                rfc.monitor_timeout = 0;
                rfc.max_pdu_size    = cpu_to_le16(L2CAP_DEFAULT_MAX_PDU_SIZE);
+               if (L2CAP_DEFAULT_MAX_PDU_SIZE > pi->conn->mtu - 10)
+                       rfc.max_pdu_size = pi->conn->mtu - 10;
 
                l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
                                        sizeof(rfc), (unsigned long) &rfc);