From 260000896750690b774d4343294ae5cbff1423e5 Mon Sep 17 00:00:00 2001 From: "Gustavo F. Padovan" Date: Tue, 11 May 2010 22:02:00 -0300 Subject: Bluetooth: Check packet FCS earlier This way, if FCS is enabled and the packet is corrupted, we just drop it without read it len, which could be corrupted. Signed-off-by: Gustavo F. Padovan Signed-off-by: Marcel Holtmann --- net/bluetooth/l2cap.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'net/bluetooth') diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c index 6094870d5d2a..8c9f577dd46d 100644 --- a/net/bluetooth/l2cap.c +++ b/net/bluetooth/l2cap.c @@ -4166,25 +4166,25 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk skb_pull(skb, 2); len = skb->len; + /* + * We can just drop the corrupted I-frame here. + * Receiver will miss it and start proper recovery + * procedures and ask retransmission. + */ + if (l2cap_check_fcs(pi, skb)) + goto drop; + if (__is_sar_start(control) && __is_iframe(control)) len -= 2; if (pi->fcs == L2CAP_FCS_CRC16) len -= 2; - /* - * We can just drop the corrupted I-frame here. - * Receiver will miss it and start proper recovery - * procedures and ask retransmission. - */ if (len > pi->mps) { l2cap_send_disconn_req(pi->conn, sk); goto drop; } - if (l2cap_check_fcs(pi, skb)) - goto drop; - req_seq = __get_reqseq(control); req_seq_offset = (req_seq - pi->expected_ack_seq) % 64; if (req_seq_offset < 0) @@ -4224,6 +4224,9 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk skb_pull(skb, 2); len = skb->len; + if (l2cap_check_fcs(pi, skb)) + goto drop; + if (__is_sar_start(control)) len -= 2; @@ -4233,9 +4236,6 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk if (len > pi->mps || len < 0 || __is_sframe(control)) goto drop; - if (l2cap_check_fcs(pi, skb)) - goto drop; - tx_seq = __get_txseq(control); if (pi->expected_tx_seq == tx_seq) -- cgit v1.2.3