Commit 81be03e0 authored by Luiz Augusto von Dentz's avatar Luiz Augusto von Dentz Committed by Marcel Holtmann
Browse files

Bluetooth: RFCOMM: Replace use of memcpy_from_msg with bt_skb_sendmmsg 



This makes use of bt_skb_sendmmsg instead using memcpy_from_msg which
is not considered safe to be used when lock_sock is held.

Also make rfcomm_dlc_send handle skb with fragments and queue them all
atomically.

Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 0771cbb3

net/bluetooth/rfcomm/core.c

+43 −7
Original line number Diff line number Diff line
@@ -549,22 +549,58 @@ struct rfcomm_dlc *rfcomm_dlc_exists(bdaddr_t *src, bdaddr_t *dst, u8 channel) 
	return dlc;

}



static int rfcomm_dlc_send_frag(struct rfcomm_dlc *d, struct sk_buff *frag)

{

	int len = frag->len;



	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);



	if (len > d->mtu)

		return -EINVAL;



	rfcomm_make_uih(frag, d->addr);

	__skb_queue_tail(&d->tx_queue, frag);



	return len;

}



int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)

{

	int len = skb->len;

	unsigned long flags;

	struct sk_buff *frag, *next;

	int len;



	if (d->state != BT_CONNECTED)

		return -ENOTCONN;



	BT_DBG("dlc %p mtu %d len %d", d, d->mtu, len);

	frag = skb_shinfo(skb)->frag_list;

	skb_shinfo(skb)->frag_list = NULL;



	if (len > d->mtu)

		return -EINVAL;

	/* Queue all fragments atomically. */

	spin_lock_irqsave(&d->tx_queue.lock, flags);



	rfcomm_make_uih(skb, d->addr);

	skb_queue_tail(&d->tx_queue, skb);

	len = rfcomm_dlc_send_frag(d, skb);

	if (len < 0 || !frag)

		goto unlock;



	for (; frag; frag = next) {

		int ret;



		next = frag->next;



		ret = rfcomm_dlc_send_frag(d, frag);

		if (ret < 0) {

			kfree_skb(frag);

			goto unlock;

		}



		len += ret;

	}



unlock:

	spin_unlock_irqrestore(&d->tx_queue.lock, flags);



	if (!test_bit(RFCOMM_TX_THROTTLED, &d->flags))

	if (len > 0 && !test_bit(RFCOMM_TX_THROTTLED, &d->flags))

		rfcomm_schedule();

	return len;

}

net/bluetooth/rfcomm/sock.c

+10 −36
Original line number Diff line number Diff line
@@ -575,46 +575,20 @@ static int rfcomm_sock_sendmsg(struct socket *sock, struct msghdr *msg, 
	lock_sock(sk);



	sent = bt_sock_wait_ready(sk, msg->msg_flags);

	if (sent)

		goto done;



	while (len) {

		size_t size = min_t(size_t, len, d->mtu);

		int err;



		skb = sock_alloc_send_skb(sk, size + RFCOMM_SKB_RESERVE,

				msg->msg_flags & MSG_DONTWAIT, &err);

		if (!skb) {

			if (sent == 0)

				sent = err;

			break;

		}

		skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);

	release_sock(sk);



		err = memcpy_from_msg(skb_put(skb, size), msg, size);

		if (err) {

			kfree_skb(skb);

			if (sent == 0)

				sent = err;

			break;

		}

	if (sent)

		return sent;



		skb->priority = sk->sk_priority;

	skb = bt_skb_sendmmsg(sk, msg, len, d->mtu, RFCOMM_SKB_HEAD_RESERVE,

			      RFCOMM_SKB_TAIL_RESERVE);

	if (IS_ERR_OR_NULL(skb))

		return PTR_ERR(skb);



		err = rfcomm_dlc_send(d, skb);

		if (err < 0) {

	sent = rfcomm_dlc_send(d, skb);

	if (sent < 0)

		kfree_skb(skb);

			if (sent == 0)

				sent = err;

			break;

		}



		sent += size;

		len  -= size;

	}



done:

	release_sock(sk);



	return sent;

}