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: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Luiz Augusto von Dentz 2021-09-03 15:27:32 -07:00 committed by Marcel Holtmann
parent 0771cbb3b9
commit 81be03e026
2 changed files with 56 additions and 46 deletions

View File

@ -549,22 +549,58 @@ struct rfcomm_dlc *rfcomm_dlc_exists(bdaddr_t *src, bdaddr_t *dst, u8 channel)
return dlc;
}
int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
static int rfcomm_dlc_send_frag(struct rfcomm_dlc *d, struct sk_buff *frag)
{
int len = skb->len;
if (d->state != BT_CONNECTED)
return -ENOTCONN;
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(skb, d->addr);
skb_queue_tail(&d->tx_queue, skb);
rfcomm_make_uih(frag, d->addr);
__skb_queue_tail(&d->tx_queue, frag);
if (!test_bit(RFCOMM_TX_THROTTLED, &d->flags))
return len;
}
int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb)
{
unsigned long flags;
struct sk_buff *frag, *next;
int len;
if (d->state != BT_CONNECTED)
return -ENOTCONN;
frag = skb_shinfo(skb)->frag_list;
skb_shinfo(skb)->frag_list = NULL;
/* Queue all fragments atomically. */
spin_lock_irqsave(&d->tx_queue.lock, flags);
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 (len > 0 && !test_bit(RFCOMM_TX_THROTTLED, &d->flags))
rfcomm_schedule();
return len;
}

View File

@ -575,47 +575,21 @@ 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);
err = memcpy_from_msg(skb_put(skb, size), msg, size);
if (err) {
kfree_skb(skb);
if (sent == 0)
sent = err;
break;
}
skb->priority = sk->sk_priority;
err = rfcomm_dlc_send(d, skb);
if (err < 0) {
kfree_skb(skb);
if (sent == 0)
sent = err;
break;
}
sent += size;
len -= size;
}
done:
release_sock(sk);
if (sent)
return sent;
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);
sent = rfcomm_dlc_send(d, skb);
if (sent < 0)
kfree_skb(skb);
return sent;
}