From 1c7621596d11b9c3e19eb88a818758dee4901c95 Mon Sep 17 00:00:00 2001 From: "Gustavo F. Padovan" Date: Sat, 1 May 2010 16:15:40 -0300 Subject: [PATCH] Bluetooth: Fix configuration of the MPS value MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit We were accepting values bigger than we can accept. This was leading ERTM to drop packets because of wrong FCS checks. Signed-off-by: Gustavo F. Padovan Reviewed-by: João Paulo Rechi Vita Signed-off-by: Marcel Holtmann --- include/net/bluetooth/l2cap.h | 3 ++- net/bluetooth/l2cap.c | 36 +++++++++++++++++++---------------- 2 files changed, 22 insertions(+), 17 deletions(-) diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h index 48f10f46c73d..0f4e4234c5fa 100644 --- a/include/net/bluetooth/l2cap.h +++ b/include/net/bluetooth/l2cap.h @@ -343,7 +343,8 @@ struct l2cap_pinfo { __u8 remote_max_tx; __u16 retrans_timeout; __u16 monitor_timeout; - __u16 max_pdu_size; + __u16 remote_mps; + __u16 mps; __le16 sport; diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c index c50c05738fb6..94be5dbb2569 100644 --- a/net/bluetooth/l2cap.c +++ b/net/bluetooth/l2cap.c @@ -1606,21 +1606,21 @@ static inline int l2cap_sar_segment_sdu(struct sock *sk, struct msghdr *msg, siz __skb_queue_head_init(&sar_queue); control = L2CAP_SDU_START; - skb = l2cap_create_iframe_pdu(sk, msg, pi->max_pdu_size, control, len); + skb = l2cap_create_iframe_pdu(sk, msg, pi->remote_mps, control, len); if (IS_ERR(skb)) return PTR_ERR(skb); __skb_queue_tail(&sar_queue, skb); - len -= pi->max_pdu_size; - size +=pi->max_pdu_size; + len -= pi->remote_mps; + size += pi->remote_mps; control = 0; while (len > 0) { size_t buflen; - if (len > pi->max_pdu_size) { + if (len > pi->remote_mps) { control |= L2CAP_SDU_CONTINUE; - buflen = pi->max_pdu_size; + buflen = pi->remote_mps; } else { control |= L2CAP_SDU_END; buflen = len; @@ -1701,7 +1701,7 @@ static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct ms case L2CAP_MODE_ERTM: case L2CAP_MODE_STREAMING: /* Entire SDU fits into one PDU */ - if (len <= pi->max_pdu_size) { + if (len <= pi->remote_mps) { control = L2CAP_SDU_UNSEGMENTED; skb = l2cap_create_iframe_pdu(sk, msg, len, control, 0); if (IS_ERR(skb)) { @@ -2330,7 +2330,7 @@ done: 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; + rfc.max_pdu_size = cpu_to_le16(pi->conn->mtu - 10); l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), (unsigned long) &rfc); @@ -2353,7 +2353,7 @@ done: 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; + rfc.max_pdu_size = cpu_to_le16(pi->conn->mtu - 10); l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc), (unsigned long) &rfc); @@ -2482,7 +2482,10 @@ done: case L2CAP_MODE_ERTM: pi->remote_tx_win = rfc.txwin_size; pi->remote_max_tx = rfc.max_transmit; - pi->max_pdu_size = rfc.max_pdu_size; + if (rfc.max_pdu_size > pi->conn->mtu - 10) + rfc.max_pdu_size = le16_to_cpu(pi->conn->mtu - 10); + + pi->remote_mps = le16_to_cpu(rfc.max_pdu_size); rfc.retrans_timeout = L2CAP_DEFAULT_RETRANS_TO; rfc.monitor_timeout = L2CAP_DEFAULT_MONITOR_TO; @@ -2495,7 +2498,10 @@ done: break; case L2CAP_MODE_STREAMING: - pi->max_pdu_size = rfc.max_pdu_size; + if (rfc.max_pdu_size > pi->conn->mtu - 10) + rfc.max_pdu_size = le16_to_cpu(pi->conn->mtu - 10); + + pi->remote_mps = le16_to_cpu(rfc.max_pdu_size); pi->conf_state |= L2CAP_CONF_MODE_DONE; @@ -2574,11 +2580,10 @@ static int l2cap_parse_conf_rsp(struct sock *sk, void *rsp, int len, void *data, pi->remote_tx_win = rfc.txwin_size; pi->retrans_timeout = rfc.retrans_timeout; pi->monitor_timeout = rfc.monitor_timeout; - pi->max_pdu_size = le16_to_cpu(rfc.max_pdu_size); + pi->mps = le16_to_cpu(rfc.max_pdu_size); break; case L2CAP_MODE_STREAMING: - pi->max_pdu_size = le16_to_cpu(rfc.max_pdu_size); - break; + pi->mps = le16_to_cpu(rfc.max_pdu_size); } } @@ -3753,7 +3758,7 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk * Receiver will miss it and start proper recovery * procedures and ask retransmission. */ - if (len > L2CAP_DEFAULT_MAX_PDU_SIZE) + if (len > pi->mps) goto drop; if (l2cap_check_fcs(pi, skb)) @@ -3784,8 +3789,7 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk if (pi->fcs == L2CAP_FCS_CRC16) len -= 2; - if (len > L2CAP_DEFAULT_MAX_PDU_SIZE || len < 4 - || __is_sframe(control)) + if (len > pi->mps || len < 4 || __is_sframe(control)) goto drop; if (l2cap_check_fcs(pi, skb)) -- 2.20.1