Commit d976092c authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

mptcp: implement MSG_TRUNC support 



The mentioned flag is currently silenlty ignored. This
change implements the TCP-like behaviour, dropping the
pending data up to the specified length.

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Sigend-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cb9d80f4

net/mptcp/protocol.c

+9 −7
Original line number Diff line number Diff line
@@ -1739,7 +1739,7 @@ static void mptcp_wait_data(struct sock *sk, long *timeo) 


static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk,

				struct msghdr *msg,

				size_t len)

				size_t len, int flags)

{

	struct sk_buff *skb;

	int copied = 0;
@@ -1750,12 +1750,14 @@ static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk, 
		u32 count = min_t(size_t, len - copied, data_len);

		int err;



		if (!(flags & MSG_TRUNC)) {

			err = skb_copy_datagram_msg(skb, offset, msg, count);

			if (unlikely(err < 0)) {

				if (!copied)

					return err;

				break;

			}

		}



		copied += count;
@@ -1966,7 +1968,7 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 
	while (copied < len) {

		int bytes_read;



		bytes_read = __mptcp_recvmsg_mskq(msk, msg, len - copied);

		bytes_read = __mptcp_recvmsg_mskq(msk, msg, len - copied, flags);

		if (unlikely(bytes_read < 0)) {

			if (!copied)

				copied = bytes_read;