Merge branch 'for-davem' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Al Viro says:

====================
netdev-related stuff in vfs.git

There are several commits sitting in vfs.git that probably ought to go in
via net-next.git.  First of all, there's merge with vfs.git#iocb - that's
Christoph's aio rework, which has triggered conflicts with the ->sendmsg()
and ->recvmsg() patches a while ago.  It's not so much Christoph's stuff
that ought to be in net-next, as (pretty simple) conflict resolution on merge.
The next chunk is switch to {compat_,}import_iovec/import_single_range - new
safer primitives for initializing iov_iter.  The primitives themselves come
from vfs/git#iov_iter (and they are used quite a lot in vfs part of queue),
conversion of net/socket.c syscalls belongs in net-next, IMO.  Next there's
afs and rxrpc stuff from dhowells.  And then there's sanitizing kernel_sendmsg
et.al.  + missing inlined helper for "how much data is left in msg->msg_iter" -
this stuff is used in e.g.  cifs stuff, but it belongs in net-next.

That pile is pullable from
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git for-davem

I'll post the individual patches in there in followups; could you take a look
and tell if everything in there is OK with you?
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

10 files changed, 196 insertions, 111 deletions

diff --git a/net/compat.c b/net/compat.c
index c4b6b0f43d5d..5cfd26a0006f 100644
--- a/net/compat.c
+++ b/net/compat.c
@@ -31,10 +31,10 @@
 #include <asm/uaccess.h>
 #include <net/compat.h>
 
-ssize_t get_compat_msghdr(struct msghdr *kmsg,
-			  struct compat_msghdr __user *umsg,
-			  struct sockaddr __user **save_addr,
-			  struct iovec **iov)
+int get_compat_msghdr(struct msghdr *kmsg,
+		      struct compat_msghdr __user *umsg,
+		      struct sockaddr __user **save_addr,
+		      struct iovec **iov)
 {
 	compat_uptr_t uaddr, uiov, tmp3;
 	compat_size_t nr_segs;
@@ -81,13 +81,9 @@ ssize_t get_compat_msghdr(struct msghdr *kmsg,
 
 	kmsg->msg_iocb = NULL;
 
-	err = compat_rw_copy_check_uvector(save_addr ? READ : WRITE,
-					   compat_ptr(uiov), nr_segs,
-					   UIO_FASTIOV, *iov, iov);
-	if (err >= 0)
-		iov_iter_init(&kmsg->msg_iter, save_addr ? READ : WRITE,
-			      *iov, nr_segs, err);
-	return err;
+	return compat_import_iovec(save_addr ? READ : WRITE,
+				   compat_ptr(uiov), nr_segs,
+				   UIO_FASTIOV, iov, &kmsg->msg_iter);
 }
 
 /* Bleech... */
diff --git a/net/core/datagram.c b/net/core/datagram.c
index df493d68330c..b80fb91bb3f7 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -673,7 +673,7 @@ int skb_copy_and_csum_datagram_msg(struct sk_buff *skb,
 	if (!chunk)
 		return 0;
 
-	if (iov_iter_count(&msg->msg_iter) < chunk) {
+	if (msg_data_left(msg) < chunk) {
 		if (__skb_checksum_complete(skb))
 			goto csum_error;
 		if (skb_copy_datagram_msg(skb, hlen, msg, chunk))
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index c0bb648fb2f9..561cd4b8fc6e 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -46,7 +46,6 @@
 #include <linux/stddef.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
-#include <linux/aio.h>
 #include <linux/kernel.h>
 #include <linux/export.h>
 #include <linux/spinlock.h>
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 094a6822c71d..18e3a12eb1b2 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1119,7 +1119,7 @@ int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 
 	sg = !!(sk->sk_route_caps & NETIF_F_SG);
 
-	while (iov_iter_count(&msg->msg_iter)) {
+	while (msg_data_left(msg)) {
 		int copy = 0;
 		int max = size_goal;
 
@@ -1163,8 +1163,8 @@ new_segment:
 		}
 
 		/* Try to append data to the end of skb. */
-		if (copy > iov_iter_count(&msg->msg_iter))
-			copy = iov_iter_count(&msg->msg_iter);
+		if (copy > msg_data_left(msg))
+			copy = msg_data_left(msg);
 
 		/* Where to copy to? */
 		if (skb_availroom(skb) > 0) {
@@ -1221,7 +1221,7 @@ new_segment:
 		tcp_skb_pcount_set(skb, 0);
 
 		copied += copy;
-		if (!iov_iter_count(&msg->msg_iter)) {
+		if (!msg_data_left(msg)) {
 			tcp_tx_timestamp(sk, skb);
 			goto out;
 		}
diff --git a/net/rxrpc/ar-input.c b/net/rxrpc/ar-input.c
index 481f89f93789..4505a691d88c 100644
--- a/net/rxrpc/ar-input.c
+++ b/net/rxrpc/ar-input.c
@@ -28,7 +28,7 @@
 const char *rxrpc_pkts[] = {
 	"?00",
 	"DATA", "ACK", "BUSY", "ABORT", "ACKALL", "CHALL", "RESP", "DEBUG",
-	"?09", "?10", "?11", "?12", "?13", "?14", "?15"
+	"?09", "?10", "?11", "?12", "VERSION", "?14", "?15"
 };
 
 /*
@@ -593,6 +593,20 @@ static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
 	rxrpc_queue_conn(conn);
 }
 
+/*
+ * post endpoint-level events to the local endpoint
+ * - this includes debug and version messages
+ */
+static void rxrpc_post_packet_to_local(struct rxrpc_local *local,
+				       struct sk_buff *skb)
+{
+	_enter("%p,%p", local, skb);
+
+	atomic_inc(&local->usage);
+	skb_queue_tail(&local->event_queue, skb);
+	rxrpc_queue_work(&local->event_processor);
+}
+
 static struct rxrpc_connection *rxrpc_conn_from_local(struct rxrpc_local *local,
 					       struct sk_buff *skb,
 					       struct rxrpc_skb_priv *sp)
@@ -699,6 +713,11 @@ void rxrpc_data_ready(struct sock *sk)
 		goto bad_message;
 	}
 
+	if (sp->hdr.type == RXRPC_PACKET_TYPE_VERSION) {
+		rxrpc_post_packet_to_local(local, skb);
+		goto out;
+	}
+	
 	if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
 	    (sp->hdr.callNumber == 0 || sp->hdr.seq == 0))
 		goto bad_message;
@@ -731,6 +750,8 @@ void rxrpc_data_ready(struct sock *sk)
 		else
 			goto cant_route_call;
 	}
+
+out:
 	rxrpc_put_local(local);
 	return;
 
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 2fc1e659e5c9..aef1bd294e17 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -152,11 +152,13 @@ struct rxrpc_local {
 	struct work_struct	destroyer;	/* endpoint destroyer */
 	struct work_struct	acceptor;	/* incoming call processor */
 	struct work_struct	rejecter;	/* packet reject writer */
+	struct work_struct	event_processor; /* endpoint event processor */
 	struct list_head	services;	/* services listening on this endpoint */
 	struct list_head	link;		/* link in endpoint list */
 	struct rw_semaphore	defrag_sem;	/* control re-enablement of IP DF bit */
 	struct sk_buff_head	accept_queue;	/* incoming calls awaiting acceptance */
 	struct sk_buff_head	reject_queue;	/* packets awaiting rejection */
+	struct sk_buff_head	event_queue;	/* endpoint event packets awaiting processing */
 	spinlock_t		lock;		/* access lock */
 	rwlock_t		services_lock;	/* lock for services list */
 	atomic_t		usage;
diff --git a/net/rxrpc/ar-local.c b/net/rxrpc/ar-local.c
index 87f7135d238b..ca904ed5400a 100644
--- a/net/rxrpc/ar-local.c
+++ b/net/rxrpc/ar-local.c
@@ -13,16 +13,22 @@
 #include <linux/net.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
+#include <linux/udp.h>
+#include <linux/ip.h>
 #include <net/sock.h>
 #include <net/af_rxrpc.h>
+#include <generated/utsrelease.h>
 #include "ar-internal.h"
 
+static const char rxrpc_version_string[65] = "linux-" UTS_RELEASE " AF_RXRPC";
+
 static LIST_HEAD(rxrpc_locals);
 DEFINE_RWLOCK(rxrpc_local_lock);
 static DECLARE_RWSEM(rxrpc_local_sem);
 static DECLARE_WAIT_QUEUE_HEAD(rxrpc_local_wq);
 
 static void rxrpc_destroy_local(struct work_struct *work);
+static void rxrpc_process_local_events(struct work_struct *work);
 
 /*
  * allocate a new local
@@ -37,11 +43,13 @@ struct rxrpc_local *rxrpc_alloc_local(struct sockaddr_rxrpc *srx)
 		INIT_WORK(&local->destroyer, &rxrpc_destroy_local);
 		INIT_WORK(&local->acceptor, &rxrpc_accept_incoming_calls);
 		INIT_WORK(&local->rejecter, &rxrpc_reject_packets);
+		INIT_WORK(&local->event_processor, &rxrpc_process_local_events);
 		INIT_LIST_HEAD(&local->services);
 		INIT_LIST_HEAD(&local->link);
 		init_rwsem(&local->defrag_sem);
 		skb_queue_head_init(&local->accept_queue);
 		skb_queue_head_init(&local->reject_queue);
+		skb_queue_head_init(&local->event_queue);
 		spin_lock_init(&local->lock);
 		rwlock_init(&local->services_lock);
 		atomic_set(&local->usage, 1);
@@ -264,10 +272,12 @@ static void rxrpc_destroy_local(struct work_struct *work)
 	ASSERT(list_empty(&local->services));
 	ASSERT(!work_pending(&local->acceptor));
 	ASSERT(!work_pending(&local->rejecter));
+	ASSERT(!work_pending(&local->event_processor));
 
 	/* finish cleaning up the local descriptor */
 	rxrpc_purge_queue(&local->accept_queue);
 	rxrpc_purge_queue(&local->reject_queue);
+	rxrpc_purge_queue(&local->event_queue);
 	kernel_sock_shutdown(local->socket, SHUT_RDWR);
 	sock_release(local->socket);
 
@@ -308,3 +318,91 @@ void __exit rxrpc_destroy_all_locals(void)
 
 	_leave("");
 }
+
+/*
+ * Reply to a version request
+ */
+static void rxrpc_send_version_request(struct rxrpc_local *local,
+				       struct rxrpc_header *hdr,
+				       struct sk_buff *skb)
+{
+	struct sockaddr_in sin;
+	struct msghdr msg;
+	struct kvec iov[2];
+	size_t len;
+	int ret;
+
+	_enter("");
+
+	sin.sin_family = AF_INET;
+	sin.sin_port = udp_hdr(skb)->source;
+	sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
+
+	msg.msg_name	= &sin;
+	msg.msg_namelen	= sizeof(sin);
+	msg.msg_control	= NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags	= 0;
+
+	hdr->seq	= 0;
+	hdr->serial	= 0;
+	hdr->type	= RXRPC_PACKET_TYPE_VERSION;
+	hdr->flags	= RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);
+	hdr->userStatus	= 0;
+	hdr->_rsvd	= 0;
+
+	iov[0].iov_base	= hdr;
+	iov[0].iov_len	= sizeof(*hdr);
+	iov[1].iov_base	= (char *)rxrpc_version_string;
+	iov[1].iov_len	= sizeof(rxrpc_version_string);
+
+	len = iov[0].iov_len + iov[1].iov_len;
+
+	_proto("Tx VERSION (reply)");
+
+	ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
+	if (ret < 0)
+		_debug("sendmsg failed: %d", ret);
+
+	_leave("");
+}
+
+/*
+ * Process event packets targetted at a local endpoint.
+ */
+static void rxrpc_process_local_events(struct work_struct *work)
+{
+	struct rxrpc_local *local = container_of(work, struct rxrpc_local, event_processor);
+	struct sk_buff *skb;
+	char v;
+
+	_enter("");
+
+	atomic_inc(&local->usage);
+	
+	while ((skb = skb_dequeue(&local->event_queue))) {
+		struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+
+		kdebug("{%d},{%u}", local->debug_id, sp->hdr.type);
+
+		switch (sp->hdr.type) {
+		case RXRPC_PACKET_TYPE_VERSION:
+			if (skb_copy_bits(skb, 0, &v, 1) < 0)
+				return;
+			_proto("Rx VERSION { %02x }", v);
+			if (v == 0)
+				rxrpc_send_version_request(local, &sp->hdr, skb);
+			break;
+
+		default:
+			/* Just ignore anything we don't understand */
+			break;
+		}
+
+		rxrpc_put_local(local);
+		rxrpc_free_skb(skb);
+	}
+
+	rxrpc_put_local(local);
+	_leave("");
+}
diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
index 09f584566e23..c0042807bfc6 100644
--- a/net/rxrpc/ar-output.c
+++ b/net/rxrpc/ar-output.c
@@ -542,11 +542,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 	call->tx_pending = NULL;
 
 	copied = 0;
-	if (len > iov_iter_count(&msg->msg_iter))
-		len = iov_iter_count(&msg->msg_iter);
-	while (len) {
-		int copy;
-
+	do {
 		if (!skb) {
 			size_t size, chunk, max, space;
 
@@ -568,8 +564,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 			max &= ~(call->conn->size_align - 1UL);
 
 			chunk = max;
-			if (chunk > len && !more)
-				chunk = len;
+			if (chunk > msg_data_left(msg) && !more)
+				chunk = msg_data_left(msg);
 
 			space = chunk + call->conn->size_align;
 			space &= ~(call->conn->size_align - 1UL);
@@ -612,23 +608,23 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 		sp = rxrpc_skb(skb);
 
 		/* append next segment of data to the current buffer */
-		copy = skb_tailroom(skb);
-		ASSERTCMP(copy, >, 0);
-		if (copy > len)
-			copy = len;
-		if (copy > sp->remain)
-			copy = sp->remain;
-
-		_debug("add");
-		ret = skb_add_data(skb, &msg->msg_iter, copy);
-		_debug("added");
-		if (ret < 0)
-			goto efault;
-		sp->remain -= copy;
-		skb->mark += copy;
-		copied += copy;
-
-		len -= copy;
+		if (msg_data_left(msg) > 0) {
+			int copy = skb_tailroom(skb);
+			ASSERTCMP(copy, >, 0);
+			if (copy > msg_data_left(msg))
+				copy = msg_data_left(msg);
+			if (copy > sp->remain)
+				copy = sp->remain;
+
+			_debug("add");
+			ret = skb_add_data(skb, &msg->msg_iter, copy);
+			_debug("added");
+			if (ret < 0)
+				goto efault;
+			sp->remain -= copy;
+			skb->mark += copy;
+			copied += copy;
+		}
 
 		/* check for the far side aborting the call or a network error
 		 * occurring */
@@ -636,7 +632,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 			goto call_aborted;
 
 		/* add the packet to the send queue if it's now full */
-		if (sp->remain <= 0 || (!len && !more)) {
+		if (sp->remain <= 0 ||
+		    (msg_data_left(msg) == 0 && !more)) {
 			struct rxrpc_connection *conn = call->conn;
 			uint32_t seq;
 			size_t pad;
@@ -666,7 +663,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 			sp->hdr.serviceId = conn->service_id;
 
 			sp->hdr.flags = conn->out_clientflag;
-			if (len == 0 && !more)
+			if (msg_data_left(msg) == 0 && !more)
 				sp->hdr.flags |= RXRPC_LAST_PACKET;
 			else if (CIRC_SPACE(call->acks_head, call->acks_tail,
 					    call->acks_winsz) > 1)
@@ -682,10 +679,10 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 
 			memcpy(skb->head, &sp->hdr,
 			       sizeof(struct rxrpc_header));
-			rxrpc_queue_packet(call, skb, !iov_iter_count(&msg->msg_iter) && !more);
+			rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
 			skb = NULL;
 		}
-	}
+	} while (msg_data_left(msg) > 0);
 
 success:
 	ret = copied;
diff --git a/net/socket.c b/net/socket.c
index 073809f4125f..5b0126234606 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -610,35 +610,27 @@ void __sock_tx_timestamp(const struct sock *sk, __u8 *tx_flags)
 }
 EXPORT_SYMBOL(__sock_tx_timestamp);
 
-static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg,
-				     size_t size)
+static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
 {
-	return sock->ops->sendmsg(sock, msg, size);
+	int ret = sock->ops->sendmsg(sock, msg, msg_data_left(msg));
+	BUG_ON(ret == -EIOCBQUEUED);
+	return ret;
 }
 
-int sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
+int sock_sendmsg(struct socket *sock, struct msghdr *msg)
 {
-	int err = security_socket_sendmsg(sock, msg, size);
+	int err = security_socket_sendmsg(sock, msg,
+					  msg_data_left(msg));
 
-	return err ?: sock_sendmsg_nosec(sock, msg, size);
+	return err ?: sock_sendmsg_nosec(sock, msg);
 }
 EXPORT_SYMBOL(sock_sendmsg);
 
 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
 		   struct kvec *vec, size_t num, size_t size)
 {
-	mm_segment_t oldfs = get_fs();
-	int result;
-
-	set_fs(KERNEL_DS);
-	/*
-	 * the following is safe, since for compiler definitions of kvec and
-	 * iovec are identical, yielding the same in-core layout and alignment
-	 */
-	iov_iter_init(&msg->msg_iter, WRITE, (struct iovec *)vec, num, size);
-	result = sock_sendmsg(sock, msg, size);
-	set_fs(oldfs);
-	return result;
+	iov_iter_kvec(&msg->msg_iter, WRITE | ITER_KVEC, vec, num, size);
+	return sock_sendmsg(sock, msg);
 }
 EXPORT_SYMBOL(kernel_sendmsg);
 
@@ -755,12 +747,8 @@ int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
 	mm_segment_t oldfs = get_fs();
 	int result;
 
+	iov_iter_kvec(&msg->msg_iter, READ | ITER_KVEC, vec, num, size);
 	set_fs(KERNEL_DS);
-	/*
-	 * the following is safe, since for compiler definitions of kvec and
-	 * iovec are identical, yielding the same in-core layout and alignment
-	 */
-	iov_iter_init(&msg->msg_iter, READ, (struct iovec *)vec, num, size);
 	result = sock_recvmsg(sock, msg, size, flags);
 	set_fs(oldfs);
 	return result;
@@ -808,10 +796,10 @@ static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
 	if (iocb->ki_pos != 0)
 		return -ESPIPE;
 
-	if (iocb->ki_nbytes == 0)	/* Match SYS5 behaviour */
+	if (!iov_iter_count(to))	/* Match SYS5 behaviour */
 		return 0;
 
-	res = sock_recvmsg(sock, &msg, iocb->ki_nbytes, msg.msg_flags);
+	res = sock_recvmsg(sock, &msg, iov_iter_count(to), msg.msg_flags);
 	*to = msg.msg_iter;
 	return res;
 }
@@ -833,7 +821,7 @@ static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	if (sock->type == SOCK_SEQPACKET)
 		msg.msg_flags |= MSG_EOR;
 
-	res = sock_sendmsg(sock, &msg, iocb->ki_nbytes);
+	res = sock_sendmsg(sock, &msg);
 	*from = msg.msg_iter;
 	return res;
 }
@@ -1650,18 +1638,14 @@ SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
 	struct iovec iov;
 	int fput_needed;
 
-	if (len > INT_MAX)
-		len = INT_MAX;
-	if (unlikely(!access_ok(VERIFY_READ, buff, len)))
-		return -EFAULT;
+	err = import_single_range(WRITE, buff, len, &iov, &msg.msg_iter);
+	if (unlikely(err))
+		return err;
 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
 
-	iov.iov_base = buff;
-	iov.iov_len = len;
 	msg.msg_name = NULL;
-	iov_iter_init(&msg.msg_iter, WRITE, &iov, 1, len);
 	msg.msg_control = NULL;
 	msg.msg_controllen = 0;
 	msg.msg_namelen = 0;
@@ -1675,7 +1659,7 @@ SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
 	if (sock->file->f_flags & O_NONBLOCK)
 		flags |= MSG_DONTWAIT;
 	msg.msg_flags = flags;
-	err = sock_sendmsg(sock, &msg, len);
+	err = sock_sendmsg(sock, &msg);
 
 out_put:
 	fput_light(sock->file, fput_needed);
@@ -1710,26 +1694,22 @@ SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
 	int err, err2;
 	int fput_needed;
 
-	if (size > INT_MAX)
-		size = INT_MAX;
-	if (unlikely(!access_ok(VERIFY_WRITE, ubuf, size)))
-		return -EFAULT;
+	err = import_single_range(READ, ubuf, size, &iov, &msg.msg_iter);
+	if (unlikely(err))
+		return err;
 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
 
 	msg.msg_control = NULL;
 	msg.msg_controllen = 0;
-	iov.iov_len = size;
-	iov.iov_base = ubuf;
-	iov_iter_init(&msg.msg_iter, READ, &iov, 1, size);
 	/* Save some cycles and don't copy the address if not needed */
 	msg.msg_name = addr ? (struct sockaddr *)&address : NULL;
 	/* We assume all kernel code knows the size of sockaddr_storage */
 	msg.msg_namelen = 0;
 	if (sock->file->f_flags & O_NONBLOCK)
 		flags |= MSG_DONTWAIT;
-	err = sock_recvmsg(sock, &msg, size, flags);
+	err = sock_recvmsg(sock, &msg, iov_iter_count(&msg.msg_iter), flags);
 
 	if (err >= 0 && addr != NULL) {
 		err2 = move_addr_to_user(&address,
@@ -1849,10 +1829,10 @@ struct used_address {
 	unsigned int name_len;
 };
 
-static ssize_t copy_msghdr_from_user(struct msghdr *kmsg,
-				     struct user_msghdr __user *umsg,
-				     struct sockaddr __user **save_addr,
-				     struct iovec **iov)
+static int copy_msghdr_from_user(struct msghdr *kmsg,
+				 struct user_msghdr __user *umsg,
+				 struct sockaddr __user **save_addr,
+				 struct iovec **iov)
 {
 	struct sockaddr __user *uaddr;
 	struct iovec __user *uiov;
@@ -1898,13 +1878,8 @@ static ssize_t copy_msghdr_from_user(struct msghdr *kmsg,
 
 	kmsg->msg_iocb = NULL;
 
-	err = rw_copy_check_uvector(save_addr ? READ : WRITE,
-				    uiov, nr_segs,
-				    UIO_FASTIOV, *iov, iov);
-	if (err >= 0)
-		iov_iter_init(&kmsg->msg_iter, save_addr ? READ : WRITE,
-			      *iov, nr_segs, err);
-	return err;
+	return import_iovec(save_addr ? READ : WRITE, uiov, nr_segs,
+			    UIO_FASTIOV, iov, &kmsg->msg_iter);
 }
 
 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
@@ -1919,7 +1894,7 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
 	    __attribute__ ((aligned(sizeof(__kernel_size_t))));
 	/* 20 is size of ipv6_pktinfo */
 	unsigned char *ctl_buf = ctl;
-	int ctl_len, total_len;
+	int ctl_len;
 	ssize_t err;
 
 	msg_sys->msg_name = &address;
@@ -1929,8 +1904,7 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
 	else
 		err = copy_msghdr_from_user(msg_sys, msg, NULL, &iov);
 	if (err < 0)
-		goto out_freeiov;
-	total_len = err;
+		return err;
 
 	err = -ENOBUFS;
 
@@ -1977,10 +1951,10 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,
 	    used_address->name_len == msg_sys->msg_namelen &&
 	    !memcmp(&used_address->name, msg_sys->msg_name,
 		    used_address->name_len)) {
-		err = sock_sendmsg_nosec(sock, msg_sys, total_len);
+		err = sock_sendmsg_nosec(sock, msg_sys);
 		goto out_freectl;
 	}
-	err = sock_sendmsg(sock, msg_sys, total_len);
+	err = sock_sendmsg(sock, msg_sys);
 	/*
 	 * If this is sendmmsg() and sending to current destination address was
 	 * successful, remember it.
@@ -1996,8 +1970,7 @@ out_freectl:
 	if (ctl_buf != ctl)
 		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
 out_freeiov:
-	if (iov != iovstack)
-		kfree(iov);
+	kfree(iov);
 	return err;
 }
 
@@ -2122,8 +2095,8 @@ static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
 	else
 		err = copy_msghdr_from_user(msg_sys, msg, &uaddr, &iov);
 	if (err < 0)
-		goto out_freeiov;
-	total_len = err;
+		return err;
+	total_len = iov_iter_count(&msg_sys->msg_iter);
 
 	cmsg_ptr = (unsigned long)msg_sys->msg_control;
 	msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
@@ -2161,8 +2134,7 @@ static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,
 	err = len;
 
 out_freeiov:
-	if (iov != iovstack)
-		kfree(iov);
+	kfree(iov);
 	return err;
 }
 
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index cc331b6cf573..0c8120229a03 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -257,7 +257,7 @@ static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 
 		svc_set_cmsg_data(rqstp, cmh);
 
-		if (sock_sendmsg(sock, &msg, 0) < 0)
+		if (sock_sendmsg(sock, &msg) < 0)
 			goto out;
 	}