Bluetooth: Refactor l2cap_retransmit_frame()
Make the code flow cleaner and changes the function to void.
It also fixes a potential NULL dereference with skb.
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 7e74d5b..1c35c32 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -1331,43 +1331,44 @@
return 0;
}
-static int l2cap_retransmit_frame(struct sock *sk, u8 tx_seq)
+static void l2cap_retransmit_frame(struct sock *sk, u8 tx_seq)
{
struct l2cap_pinfo *pi = l2cap_pi(sk);
struct sk_buff *skb, *tx_skb;
u16 control, fcs;
skb = skb_peek(TX_QUEUE(sk));
+ if (!skb)
+ return;
+
do {
- if (bt_cb(skb)->tx_seq != tx_seq) {
- if (skb_queue_is_last(TX_QUEUE(sk), skb))
- break;
- skb = skb_queue_next(TX_QUEUE(sk), skb);
- continue;
- }
-
- if (pi->remote_max_tx &&
- bt_cb(skb)->retries == pi->remote_max_tx) {
- l2cap_send_disconn_req(pi->conn, sk);
+ if (bt_cb(skb)->tx_seq == tx_seq)
break;
- }
- tx_skb = skb_clone(skb, GFP_ATOMIC);
- bt_cb(skb)->retries++;
- control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
- control |= (pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT)
- | (tx_seq << L2CAP_CTRL_TXSEQ_SHIFT);
- put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
+ if (skb_queue_is_last(TX_QUEUE(sk), skb))
+ return;
- if (pi->fcs == L2CAP_FCS_CRC16) {
- fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2);
- put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
- }
+ } while ((skb = skb_queue_next(TX_QUEUE(sk), skb)));
- l2cap_do_send(sk, tx_skb);
- break;
- } while(1);
- return 0;
+ if (pi->remote_max_tx &&
+ bt_cb(skb)->retries == pi->remote_max_tx) {
+ l2cap_send_disconn_req(pi->conn, sk);
+ return;
+ }
+
+ tx_skb = skb_clone(skb, GFP_ATOMIC);
+ bt_cb(skb)->retries++;
+ control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
+ control |= (pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT)
+ | (tx_seq << L2CAP_CTRL_TXSEQ_SHIFT);
+ put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
+
+ if (pi->fcs == L2CAP_FCS_CRC16) {
+ fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2);
+ put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
+ }
+
+ l2cap_do_send(sk, tx_skb);
}
static int l2cap_ertm_send(struct sock *sk)