Commit 037f103d authored Jul 20, 2020 by David Howells Committed by Greg Kroah-Hartman Jul 31, 2020

rxrpc: Fix sendmsg() returning EPIPE due to recvmsg() returning ENODATA



[ Upstream commit 639f181f0ee20d3249dbc55f740f0167267180f0 ]

rxrpc_sendmsg() returns EPIPE if there's an outstanding error, such as if
rxrpc_recvmsg() indicating ENODATA if there's nothing for it to read.

Change rxrpc_recvmsg() to return EAGAIN instead if there's nothing to read
as this particular error doesn't get stored in ->sk_err by the networking
core.

Also change rxrpc_sendmsg() so that it doesn't fail with delayed receive
errors (there's no way for it to report which call, if any, the error was
caused by).

Fixes: 17926a79 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4b864ae6

net/rxrpc/recvmsg.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -453,7 +453,7 @@ int rxrpc_recvmsg(struct socket sock, struct msghdr msg, size_t len,
	list_empty(&rx->recvmsg_q) &&		list_empty(&rx->recvmsg_q) &&
	rx->sk.sk_state != RXRPC_SERVER_LISTENING) {		rx->sk.sk_state != RXRPC_SERVER_LISTENING) {
	release_sock(&rx->sk);		release_sock(&rx->sk);
	return -ENODATA;		return -EAGAIN;
	}		}

	if (list_empty(&rx->recvmsg_q)) {		if (list_empty(&rx->recvmsg_q)) {

net/rxrpc/sendmsg.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -278,7 +278,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
	/* this should be in poll */		/* this should be in poll */
	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);		sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);

	if (sk->sk_err \|\| (sk->sk_shutdown & SEND_SHUTDOWN))		if (sk->sk_shutdown & SEND_SHUTDOWN)
	return -EPIPE;		return -EPIPE;

	more = msg->msg_flags & MSG_MORE;		more = msg->msg_flags & MSG_MORE;