[PATCH net-next 00/10] mptcp: New features for MPTCP sockets and netlink PM

[PATCH net-next 00/10] mptcp: New features for MPTCP sockets and netlink PM

[Mat Martineau]

This collection of patches adds MPTCP socket support for a few socket
options, ioctls, and one ancillary data type (specifics for each are
listed below). There's also a patch modifying the netlink MPTCP path
manager API to allow setting the backup flag on a configured interface
using the endpoint ID instead of the full IP address.

Patches 1 & 2: TCP_INQ cmsg and selftests.

Patches 2 & 3: SIOCINQ, OUTQ, and OUTQNSD ioctls and selftests.

Patch 5: Change backup flag using endpoint ID.

Patches 6 & 7: IP_TOS socket option and selftests.

Patches 8-10: TCP_CORK and TCP_NODELAY socket options. Includes a tcp
change to expose __tcp_sock_set_cork() and __tcp_sock_set_nodelay() for
use by MPTCP.


Davide Caratti (1):
  mptcp: allow changing the "backup" bit by endpoint id

Florian Westphal (6):
  mptcp: add TCP_INQ cmsg support
  selftests: mptcp: add TCP_INQ support
  mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls
  selftests: mptcp: add inq test case
  mptcp: getsockopt: add support for IP_TOS
  selftests: mptcp: check IP_TOS in/out are the same

Maxim Galaganov (3):
  tcp: expose __tcp_sock_set_cork and __tcp_sock_set_nodelay
  mptcp: expose mptcp_check_and_set_pending
  mptcp: support TCP_CORK and TCP_NODELAY

 include/linux/tcp.h                           |   2 +
 net/ipv4/tcp.c                                |   4 +-
 net/mptcp/pm_netlink.c                        |  14 +-
 net/mptcp/protocol.c                          |  91 ++-
 net/mptcp/protocol.h                          |   4 +
 net/mptcp/sockopt.c                           | 132 +++-
 tools/testing/selftests/net/mptcp/.gitignore  |   1 +
 tools/testing/selftests/net/mptcp/Makefile    |   2 +-
 .../selftests/net/mptcp/mptcp_connect.c       |  60 +-
 tools/testing/selftests/net/mptcp/mptcp_inq.c | 603 ++++++++++++++++++
 .../selftests/net/mptcp/mptcp_sockopt.c       |  63 ++
 .../selftests/net/mptcp/mptcp_sockopt.sh      |  44 +-
 12 files changed, 1007 insertions(+), 13 deletions(-)
 create mode 100644 tools/testing/selftests/net/mptcp/mptcp_inq.c


base-commit: bb14bfc7eb927b47717d82ba7ecc8345d9099cf4
-- 
2.34.1

[PATCH net-next 01/10] mptcp: add TCP_INQ cmsg support

[Mat Martineau]

From: Florian Westphal <fw@strlen.de>

Support the TCP_INQ setsockopt.

This is a boolean that tells recvmsg path to include the remaining
in-sequence bytes in the cmsg data.

v2: do not use CB(skb)->offset, increment map_seq instead (Paolo Abeni)
v3: adjust CB(skb)->map_seq when taking skb from ofo queue (Paolo Abeni)

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/224
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/protocol.c | 36 +++++++++++++++++++++++++++++++++++-
 net/mptcp/protocol.h |  1 +
 net/mptcp/sockopt.c  | 38 +++++++++++++++++++++++++++++++++++++-
 3 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index b100048e43fe..ffc8068aaad0 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -46,6 +46,7 @@ struct mptcp_skb_cb {
 
 enum {
 	MPTCP_CMSG_TS = BIT(0),
+	MPTCP_CMSG_INQ = BIT(1),
 };
 
 static struct percpu_counter mptcp_sockets_allocated ____cacheline_aligned_in_smp;
@@ -738,6 +739,7 @@ static bool __mptcp_ofo_queue(struct mptcp_sock *msk)
 				 MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq,
 				 delta);
 			MPTCP_SKB_CB(skb)->offset += delta;
+			MPTCP_SKB_CB(skb)->map_seq += delta;
 			__skb_queue_tail(&sk->sk_receive_queue, skb);
 		}
 		msk->ack_seq = end_seq;
@@ -1784,8 +1786,10 @@ static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk,
 		copied += count;
 
 		if (count < data_len) {
-			if (!(flags & MSG_PEEK))
+			if (!(flags & MSG_PEEK)) {
 				MPTCP_SKB_CB(skb)->offset += count;
+				MPTCP_SKB_CB(skb)->map_seq += count;
+			}
 			break;
 		}
 
@@ -1965,6 +1969,27 @@ static bool __mptcp_move_skbs(struct mptcp_sock *msk)
 	return !skb_queue_empty(&msk->receive_queue);
 }
 
+static unsigned int mptcp_inq_hint(const struct sock *sk)
+{
+	const struct mptcp_sock *msk = mptcp_sk(sk);
+	const struct sk_buff *skb;
+
+	skb = skb_peek(&msk->receive_queue);
+	if (skb) {
+		u64 hint_val = msk->ack_seq - MPTCP_SKB_CB(skb)->map_seq;
+
+		if (hint_val >= INT_MAX)
+			return INT_MAX;
+
+		return (unsigned int)hint_val;
+	}
+
+	if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN))
+		return 1;
+
+	return 0;
+}
+
 static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 			 int nonblock, int flags, int *addr_len)
 {
@@ -1989,6 +2014,9 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	len = min_t(size_t, len, INT_MAX);
 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
 
+	if (unlikely(msk->recvmsg_inq))
+		cmsg_flags = MPTCP_CMSG_INQ;
+
 	while (copied < len) {
 		int bytes_read;
 
@@ -2062,6 +2090,12 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	if (cmsg_flags && copied >= 0) {
 		if (cmsg_flags & MPTCP_CMSG_TS)
 			tcp_recv_timestamp(msg, sk, &tss);
+
+		if (cmsg_flags & MPTCP_CMSG_INQ) {
+			unsigned int inq = mptcp_inq_hint(sk);
+
+			put_cmsg(msg, SOL_TCP, TCP_CM_INQ, sizeof(inq), &inq);
+		}
 	}
 
 	pr_debug("msk=%p rx queue empty=%d:%d copied=%d",
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index d87cc040352e..bb51fa7f5566 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -249,6 +249,7 @@ struct mptcp_sock {
 	bool		rcv_fastclose;
 	bool		use_64bit_ack; /* Set when we received a 64-bit DSN */
 	bool		csum_enabled;
+	u8		recvmsg_inq:1;
 	spinlock_t	join_list_lock;
 	struct work_struct work;
 	struct sk_buff  *ooo_last_skb;
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index fb43e145cb57..11cda8629993 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -557,6 +557,7 @@ static bool mptcp_supported_sockopt(int level, int optname)
 		case TCP_TIMESTAMP:
 		case TCP_NOTSENT_LOWAT:
 		case TCP_TX_DELAY:
+		case TCP_INQ:
 			return true;
 		}
 
@@ -568,7 +569,6 @@ static bool mptcp_supported_sockopt(int level, int optname)
 		/* TCP_FASTOPEN_KEY, TCP_FASTOPEN TCP_FASTOPEN_CONNECT, TCP_FASTOPEN_NO_COOKIE,
 		 * are not supported fastopen is currently unsupported
 		 */
-		/* TCP_INQ is currently unsupported, needs some recvmsg work */
 	}
 	return false;
 }
@@ -698,7 +698,21 @@ static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname,
 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 				    sockptr_t optval, unsigned int optlen)
 {
+	struct sock *sk = (void *)msk;
+	int ret, val;
+
 	switch (optname) {
+	case TCP_INQ:
+		ret = mptcp_get_int_option(msk, optval, optlen, &val);
+		if (ret)
+			return ret;
+		if (val < 0 || val > 1)
+			return -EINVAL;
+
+		lock_sock(sk);
+		msk->recvmsg_inq = !!val;
+		release_sock(sk);
+		return 0;
 	case TCP_ULP:
 		return -EOPNOTSUPP;
 	case TCP_CONGESTION:
@@ -1032,6 +1046,26 @@ static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *o
 	return 0;
 }
 
+static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
+				int __user *optlen, int val)
+{
+	int len;
+
+	if (get_user(len, optlen))
+		return -EFAULT;
+
+	len = min_t(unsigned int, len, sizeof(int));
+	if (len < 0)
+		return -EINVAL;
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+	if (copy_to_user(optval, &val, len))
+		return -EFAULT;
+
+	return 0;
+}
+
 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 				    char __user *optval, int __user *optlen)
 {
@@ -1042,6 +1076,8 @@ static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 	case TCP_CC_INFO:
 		return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname,
 						      optval, optlen);
+	case TCP_INQ:
+		return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq);
 	}
 	return -EOPNOTSUPP;
 }
-- 
2.34.1

Re: [PATCH net-next 01/10] mptcp: add TCP_INQ cmsg support

[Jakub Kicinski]

On Fri,  3 Dec 2021 14:35:32 -0800 Mat Martineau wrote:
> +static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
> +				int __user *optlen, int val)
> +{
> +	int len;
> +
> +	if (get_user(len, optlen))
> +		return -EFAULT;
> +
> +	len = min_t(unsigned int, len, sizeof(int));
> +	if (len < 0)
> +		return -EINVAL;

TCP has the same statement but surely it's dead code?

min_t(unsigned, .., 4)

cannot return anything outside of the range from 0 to 4.

> +	if (put_user(len, optlen))
> +		return -EFAULT;
> +	if (copy_to_user(optval, &val, len))
> +		return -EFAULT;
> +
> +	return 0;

[PATCH net-next 02/10] selftests: mptcp: add TCP_INQ support

[Mat Martineau]

From: Florian Westphal <fw@strlen.de>

Do checks on the returned inq counter.

Fail on:
1. Huge value (> 1 kbyte, test case files are 1 kb)
2. last hint larger than returned bytes when read was short
3. erronenous indication of EOF.

3) happens when a hint of X bytes reads X-1 on next call
   but next recvmsg returns more data (instead of EOF).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 .../selftests/net/mptcp/mptcp_connect.c       | 60 ++++++++++++++++++-
 .../selftests/net/mptcp/mptcp_sockopt.sh      |  4 +-
 2 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.c b/tools/testing/selftests/net/mptcp/mptcp_connect.c
index ada9b80774d4..98de28ac3ba8 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.c
@@ -73,12 +73,20 @@ static uint32_t cfg_mark;
 struct cfg_cmsg_types {
 	unsigned int cmsg_enabled:1;
 	unsigned int timestampns:1;
+	unsigned int tcp_inq:1;
 };
 
 struct cfg_sockopt_types {
 	unsigned int transparent:1;
 };
 
+struct tcp_inq_state {
+	unsigned int last;
+	bool expect_eof;
+};
+
+static struct tcp_inq_state tcp_inq;
+
 static struct cfg_cmsg_types cfg_cmsg_types;
 static struct cfg_sockopt_types cfg_sockopt_types;
 
@@ -389,7 +397,9 @@ static size_t do_write(const int fd, char *buf, const size_t len)
 static void process_cmsg(struct msghdr *msgh)
 {
 	struct __kernel_timespec ts;
+	bool inq_found = false;
 	bool ts_found = false;
+	unsigned int inq = 0;
 	struct cmsghdr *cmsg;
 
 	for (cmsg = CMSG_FIRSTHDR(msgh); cmsg ; cmsg = CMSG_NXTHDR(msgh, cmsg)) {
@@ -398,12 +408,27 @@ static void process_cmsg(struct msghdr *msgh)
 			ts_found = true;
 			continue;
 		}
+		if (cmsg->cmsg_level == IPPROTO_TCP && cmsg->cmsg_type == TCP_CM_INQ) {
+			memcpy(&inq, CMSG_DATA(cmsg), sizeof(inq));
+			inq_found = true;
+			continue;
+		}
+
 	}
 
 	if (cfg_cmsg_types.timestampns) {
 		if (!ts_found)
 			xerror("TIMESTAMPNS not present\n");
 	}
+
+	if (cfg_cmsg_types.tcp_inq) {
+		if (!inq_found)
+			xerror("TCP_INQ not present\n");
+
+		if (inq > 1024)
+			xerror("tcp_inq %u is larger than one kbyte\n", inq);
+		tcp_inq.last = inq;
+	}
 }
 
 static ssize_t do_recvmsg_cmsg(const int fd, char *buf, const size_t len)
@@ -420,10 +445,23 @@ static ssize_t do_recvmsg_cmsg(const int fd, char *buf, const size_t len)
 		.msg_controllen = sizeof(msg_buf),
 	};
 	int flags = 0;
+	unsigned int last_hint = tcp_inq.last;
 	int ret = recvmsg(fd, &msg, flags);
 
-	if (ret <= 0)
+	if (ret <= 0) {
+		if (ret == 0 && tcp_inq.expect_eof)
+			return ret;
+
+		if (ret == 0 && cfg_cmsg_types.tcp_inq)
+			if (last_hint != 1 && last_hint != 0)
+				xerror("EOF but last tcp_inq hint was %u\n", last_hint);
+
 		return ret;
+	}
+
+	if (tcp_inq.expect_eof)
+		xerror("expected EOF, last_hint %u, now %u\n",
+		       last_hint, tcp_inq.last);
 
 	if (msg.msg_controllen && !cfg_cmsg_types.cmsg_enabled)
 		xerror("got %lu bytes of cmsg data, expected 0\n",
@@ -435,6 +473,19 @@ static ssize_t do_recvmsg_cmsg(const int fd, char *buf, const size_t len)
 	if (msg.msg_controllen)
 		process_cmsg(&msg);
 
+	if (cfg_cmsg_types.tcp_inq) {
+		if ((size_t)ret < len && last_hint > (unsigned int)ret) {
+			if (ret + 1 != (int)last_hint) {
+				int next = read(fd, msg_buf, sizeof(msg_buf));
+
+				xerror("read %u of %u, last_hint was %u tcp_inq hint now %u next_read returned %d/%m\n",
+				       ret, (unsigned int)len, last_hint, tcp_inq.last, next);
+			} else {
+				tcp_inq.expect_eof = true;
+			}
+		}
+	}
+
 	return ret;
 }
 
@@ -944,6 +995,8 @@ static void apply_cmsg_types(int fd, const struct cfg_cmsg_types *cmsg)
 
 	if (cmsg->timestampns)
 		xsetsockopt(fd, SOL_SOCKET, SO_TIMESTAMPNS_NEW, &on, sizeof(on));
+	if (cmsg->tcp_inq)
+		xsetsockopt(fd, IPPROTO_TCP, TCP_INQ, &on, sizeof(on));
 }
 
 static void parse_cmsg_types(const char *type)
@@ -965,6 +1018,11 @@ static void parse_cmsg_types(const char *type)
 		return;
 	}
 
+	if (strncmp(type, "TCPINQ", len) == 0) {
+		cfg_cmsg_types.tcp_inq = 1;
+		return;
+	}
+
 	fprintf(stderr, "Unrecognized cmsg option %s\n", type);
 	exit(1);
 }
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
index 41de643788b8..c8c364369599 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
@@ -178,7 +178,7 @@ do_transfer()
 
 	timeout ${timeout_test} \
 		ip netns exec ${listener_ns} \
-			$mptcp_connect -t ${timeout_poll} -l -M 1 -p $port -s ${srv_proto} -c TIMESTAMPNS \
+			$mptcp_connect -t ${timeout_poll} -l -M 1 -p $port -s ${srv_proto} -c TIMESTAMPNS,TCPINQ \
 				${local_addr} < "$sin" > "$sout" &
 	spid=$!
 
@@ -186,7 +186,7 @@ do_transfer()
 
 	timeout ${timeout_test} \
 		ip netns exec ${connector_ns} \
-			$mptcp_connect -t ${timeout_poll} -M 2 -p $port -s ${cl_proto} -c TIMESTAMPNS \
+			$mptcp_connect -t ${timeout_poll} -M 2 -p $port -s ${cl_proto} -c TIMESTAMPNS,TCPINQ \
 				$connect_addr < "$cin" > "$cout" &
 
 	cpid=$!
-- 
2.34.1

[PATCH net-next 03/10] mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls

[Mat Martineau]

From: Florian Westphal <fw@strlen.de>

Allows to query in-sequence data ready for read(), total bytes in
write queue and total bytes in write queue that have not yet been sent.

v2: remove unneeded READ_ONCE() (Paolo Abeni)
v3: check for new data unconditionally in SIOCINQ ioctl (Mat Martineau)

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/protocol.c | 53 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index ffc8068aaad0..943f74e804bd 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -22,6 +22,7 @@
 #endif
 #include <net/mptcp.h>
 #include <net/xfrm.h>
+#include <asm/ioctls.h>
 #include "protocol.h"
 #include "mib.h"
 
@@ -3211,6 +3212,57 @@ static int mptcp_forward_alloc_get(const struct sock *sk)
 	return sk->sk_forward_alloc + mptcp_sk(sk)->rmem_fwd_alloc;
 }
 
+static int mptcp_ioctl_outq(const struct mptcp_sock *msk, u64 v)
+{
+	const struct sock *sk = (void *)msk;
+	u64 delta;
+
+	if (sk->sk_state == TCP_LISTEN)
+		return -EINVAL;
+
+	if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
+		return 0;
+
+	delta = msk->write_seq - v;
+	if (delta > INT_MAX)
+		delta = INT_MAX;
+
+	return (int)delta;
+}
+
+static int mptcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+	struct mptcp_sock *msk = mptcp_sk(sk);
+	bool slow;
+	int answ;
+
+	switch (cmd) {
+	case SIOCINQ:
+		if (sk->sk_state == TCP_LISTEN)
+			return -EINVAL;
+
+		lock_sock(sk);
+		__mptcp_move_skbs(msk);
+		answ = mptcp_inq_hint(sk);
+		release_sock(sk);
+		break;
+	case SIOCOUTQ:
+		slow = lock_sock_fast(sk);
+		answ = mptcp_ioctl_outq(msk, READ_ONCE(msk->snd_una));
+		unlock_sock_fast(sk, slow);
+		break;
+	case SIOCOUTQNSD:
+		slow = lock_sock_fast(sk);
+		answ = mptcp_ioctl_outq(msk, msk->snd_nxt);
+		unlock_sock_fast(sk, slow);
+		break;
+	default:
+		return -ENOIOCTLCMD;
+	}
+
+	return put_user(answ, (int __user *)arg);
+}
+
 static struct proto mptcp_prot = {
 	.name		= "MPTCP",
 	.owner		= THIS_MODULE,
@@ -3223,6 +3275,7 @@ static struct proto mptcp_prot = {
 	.shutdown	= mptcp_shutdown,
 	.destroy	= mptcp_destroy,
 	.sendmsg	= mptcp_sendmsg,
+	.ioctl		= mptcp_ioctl,
 	.recvmsg	= mptcp_recvmsg,
 	.release_cb	= mptcp_release_cb,
 	.hash		= mptcp_hash,
-- 
2.34.1

Re: [PATCH net-next 03/10] mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls

[Jakub Kicinski]

On Fri,  3 Dec 2021 14:35:34 -0800 Mat Martineau wrote:
> +		if (sk->sk_state == TCP_LISTEN)
> +			return -EINVAL;
> +
> +		lock_sock(sk);
> +		__mptcp_move_skbs(msk);
> +		answ = mptcp_inq_hint(sk);
> +		release_sock(sk);

The raciness is not harmful here?

Re: [PATCH net-next 03/10] mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls

[Florian Westphal]

Jakub Kicinski <kuba@kernel.org> wrote:
> On Fri,  3 Dec 2021 14:35:34 -0800 Mat Martineau wrote:
> > +		if (sk->sk_state == TCP_LISTEN)
> > +			return -EINVAL;
> > +
> > +		lock_sock(sk);
> > +		__mptcp_move_skbs(msk);
> > +		answ = mptcp_inq_hint(sk);
> > +		release_sock(sk);
> 
> The raciness is not harmful here?

Can you elaborate?  We can't prevent new data
from being queued after this, but it won't decrease
on its own either, i.e. we only guarantee that we have at
least answ bytes for read().

Re: [PATCH net-next 03/10] mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls

[Paolo Abeni]

Hello,

On Mon, 2021-12-06 at 17:16 -0800, Jakub Kicinski wrote:
> On Fri,  3 Dec 2021 14:35:34 -0800 Mat Martineau wrote:
> > +		if (sk->sk_state == TCP_LISTEN)
> > +			return -EINVAL;
> > +
> > +		lock_sock(sk);
> > +		__mptcp_move_skbs(msk);
> > +		answ = mptcp_inq_hint(sk);
> > +		release_sock(sk);
> 
> The raciness is not harmful here?

Thank you for the careful review!

AFAICS the race between the socket state test and the receive queue
lenght estimate is not harmful: if a socket is concurrently
disconnected and moved to a listen status, mptcp_inq_hint() will return
0, as plain TCP would do in the same scenario - all the fields accessed
by __mptcp_move_skbs() and mptcp_inq_hint() will be in a consistant
status (modulo unknown bugs).

Cheers,

Paolo

[PATCH net-next 04/10] selftests: mptcp: add inq test case

[Mat Martineau]

From: Florian Westphal <fw@strlen.de>

client & server use a unix socket connection to communicate
outside of the mptcp connection.

This allows the consumer to know in advance how many bytes have been
(or will be) sent by the peer.
This allows stricter checks on the bytecounts reported by TCP_INQ cmsg.

Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 tools/testing/selftests/net/mptcp/.gitignore  |   1 +
 tools/testing/selftests/net/mptcp/Makefile    |   2 +-
 tools/testing/selftests/net/mptcp/mptcp_inq.c | 603 ++++++++++++++++++
 .../selftests/net/mptcp/mptcp_sockopt.sh      |  40 ++
 4 files changed, 645 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/net/mptcp/mptcp_inq.c

diff --git a/tools/testing/selftests/net/mptcp/.gitignore b/tools/testing/selftests/net/mptcp/.gitignore
index 7569d892967a..49daae73c41e 100644
--- a/tools/testing/selftests/net/mptcp/.gitignore
+++ b/tools/testing/selftests/net/mptcp/.gitignore
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
 mptcp_connect
+mptcp_inq
 mptcp_sockopt
 pm_nl_ctl
 *.pcap
diff --git a/tools/testing/selftests/net/mptcp/Makefile b/tools/testing/selftests/net/mptcp/Makefile
index bbf4e448bad9..0356c4501c99 100644
--- a/tools/testing/selftests/net/mptcp/Makefile
+++ b/tools/testing/selftests/net/mptcp/Makefile
@@ -8,7 +8,7 @@ CFLAGS =  -Wall -Wl,--no-as-needed -O2 -g  -I$(top_srcdir)/usr/include
 TEST_PROGS := mptcp_connect.sh pm_netlink.sh mptcp_join.sh diag.sh \
 	      simult_flows.sh mptcp_sockopt.sh
 
-TEST_GEN_FILES = mptcp_connect pm_nl_ctl mptcp_sockopt
+TEST_GEN_FILES = mptcp_connect pm_nl_ctl mptcp_sockopt mptcp_inq
 
 TEST_FILES := settings
 
diff --git a/tools/testing/selftests/net/mptcp/mptcp_inq.c b/tools/testing/selftests/net/mptcp/mptcp_inq.c
new file mode 100644
index 000000000000..b8debd4fb5ed
--- /dev/null
+++ b/tools/testing/selftests/net/mptcp/mptcp_inq.c
@@ -0,0 +1,603 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <unistd.h>
+#include <time.h>
+
+#include <sys/ioctl.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <netdb.h>
+#include <netinet/in.h>
+
+#include <linux/tcp.h>
+#include <linux/sockios.h>
+
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
+#ifndef SOL_MPTCP
+#define SOL_MPTCP 284
+#endif
+
+static int pf = AF_INET;
+static int proto_tx = IPPROTO_MPTCP;
+static int proto_rx = IPPROTO_MPTCP;
+
+static void die_perror(const char *msg)
+{
+	perror(msg);
+	exit(1);
+}
+
+static void die_usage(int r)
+{
+	fprintf(stderr, "Usage: mptcp_inq [-6] [ -t tcp|mptcp ] [ -r tcp|mptcp]\n");
+	exit(r);
+}
+
+static void xerror(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fputc('\n', stderr);
+	exit(1);
+}
+
+static const char *getxinfo_strerr(int err)
+{
+	if (err == EAI_SYSTEM)
+		return strerror(errno);
+
+	return gai_strerror(err);
+}
+
+static void xgetaddrinfo(const char *node, const char *service,
+			 const struct addrinfo *hints,
+			 struct addrinfo **res)
+{
+	int err = getaddrinfo(node, service, hints, res);
+
+	if (err) {
+		const char *errstr = getxinfo_strerr(err);
+
+		fprintf(stderr, "Fatal: getaddrinfo(%s:%s): %s\n",
+			node ? node : "", service ? service : "", errstr);
+		exit(1);
+	}
+}
+
+static int sock_listen_mptcp(const char * const listenaddr,
+			     const char * const port)
+{
+	int sock;
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+		.ai_flags = AI_PASSIVE | AI_NUMERICHOST
+	};
+
+	hints.ai_family = pf;
+
+	struct addrinfo *a, *addr;
+	int one = 1;
+
+	xgetaddrinfo(listenaddr, port, &hints, &addr);
+	hints.ai_family = pf;
+
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, proto_rx);
+		if (sock < 0)
+			continue;
+
+		if (-1 == setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one,
+				     sizeof(one)))
+			perror("setsockopt");
+
+		if (bind(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		perror("bind");
+		close(sock);
+		sock = -1;
+	}
+
+	freeaddrinfo(addr);
+
+	if (sock < 0)
+		xerror("could not create listen socket");
+
+	if (listen(sock, 20))
+		die_perror("listen");
+
+	return sock;
+}
+
+static int sock_connect_mptcp(const char * const remoteaddr,
+			      const char * const port, int proto)
+{
+	struct addrinfo hints = {
+		.ai_protocol = IPPROTO_TCP,
+		.ai_socktype = SOCK_STREAM,
+	};
+	struct addrinfo *a, *addr;
+	int sock = -1;
+
+	hints.ai_family = pf;
+
+	xgetaddrinfo(remoteaddr, port, &hints, &addr);
+	for (a = addr; a; a = a->ai_next) {
+		sock = socket(a->ai_family, a->ai_socktype, proto);
+		if (sock < 0)
+			continue;
+
+		if (connect(sock, a->ai_addr, a->ai_addrlen) == 0)
+			break; /* success */
+
+		die_perror("connect");
+	}
+
+	if (sock < 0)
+		xerror("could not create connect socket");
+
+	freeaddrinfo(addr);
+	return sock;
+}
+
+static int protostr_to_num(const char *s)
+{
+	if (strcasecmp(s, "tcp") == 0)
+		return IPPROTO_TCP;
+	if (strcasecmp(s, "mptcp") == 0)
+		return IPPROTO_MPTCP;
+
+	die_usage(1);
+	return 0;
+}
+
+static void parse_opts(int argc, char **argv)
+{
+	int c;
+
+	while ((c = getopt(argc, argv, "h6t:r:")) != -1) {
+		switch (c) {
+		case 'h':
+			die_usage(0);
+			break;
+		case '6':
+			pf = AF_INET6;
+			break;
+		case 't':
+			proto_tx = protostr_to_num(optarg);
+			break;
+		case 'r':
+			proto_rx = protostr_to_num(optarg);
+			break;
+		default:
+			die_usage(1);
+			break;
+		}
+	}
+}
+
+/* wait up to timeout milliseconds */
+static void wait_for_ack(int fd, int timeout, size_t total)
+{
+	int i;
+
+	for (i = 0; i < timeout; i++) {
+		int nsd, ret, queued = -1;
+		struct timespec req;
+
+		ret = ioctl(fd, TIOCOUTQ, &queued);
+		if (ret < 0)
+			die_perror("TIOCOUTQ");
+
+		ret = ioctl(fd, SIOCOUTQNSD, &nsd);
+		if (ret < 0)
+			die_perror("SIOCOUTQNSD");
+
+		if ((size_t)queued > total)
+			xerror("TIOCOUTQ %u, but only %zu expected\n", queued, total);
+		assert(nsd <= queued);
+
+		if (queued == 0)
+			return;
+
+		/* wait for peer to ack rx of all data */
+		req.tv_sec = 0;
+		req.tv_nsec = 1 * 1000 * 1000ul; /* 1ms */
+		nanosleep(&req, NULL);
+	}
+
+	xerror("still tx data queued after %u ms\n", timeout);
+}
+
+static void connect_one_server(int fd, int unixfd)
+{
+	size_t len, i, total, sent;
+	char buf[4096], buf2[4096];
+	ssize_t ret;
+
+	len = rand() % (sizeof(buf) - 1);
+
+	if (len < 128)
+		len = 128;
+
+	for (i = 0; i < len ; i++) {
+		buf[i] = rand() % 26;
+		buf[i] += 'A';
+	}
+
+	buf[i] = '\n';
+
+	/* un-block server */
+	ret = read(unixfd, buf2, 4);
+	assert(ret == 4);
+
+	assert(strncmp(buf2, "xmit", 4) == 0);
+
+	ret = write(unixfd, &len, sizeof(len));
+	assert(ret == (ssize_t)sizeof(len));
+
+	ret = write(fd, buf, len);
+	if (ret < 0)
+		die_perror("write");
+
+	if (ret != (ssize_t)len)
+		xerror("short write");
+
+	ret = read(unixfd, buf2, 4);
+	assert(strncmp(buf2, "huge", 4) == 0);
+
+	total = rand() % (16 * 1024 * 1024);
+	total += (1 * 1024 * 1024);
+	sent = total;
+
+	ret = write(unixfd, &total, sizeof(total));
+	assert(ret == (ssize_t)sizeof(total));
+
+	wait_for_ack(fd, 5000, len);
+
+	while (total > 0) {
+		if (total > sizeof(buf))
+			len = sizeof(buf);
+		else
+			len = total;
+
+		ret = write(fd, buf, len);
+		if (ret < 0)
+			die_perror("write");
+		total -= ret;
+
+		/* we don't have to care about buf content, only
+		 * number of total bytes sent
+		 */
+	}
+
+	ret = read(unixfd, buf2, 4);
+	assert(ret == 4);
+	assert(strncmp(buf2, "shut", 4) == 0);
+
+	wait_for_ack(fd, 5000, sent);
+
+	ret = write(fd, buf, 1);
+	assert(ret == 1);
+	close(fd);
+	ret = write(unixfd, "closed", 6);
+	assert(ret == 6);
+
+	close(unixfd);
+}
+
+static void get_tcp_inq(struct msghdr *msgh, unsigned int *inqv)
+{
+	struct cmsghdr *cmsg;
+
+	for (cmsg = CMSG_FIRSTHDR(msgh); cmsg ; cmsg = CMSG_NXTHDR(msgh, cmsg)) {
+		if (cmsg->cmsg_level == IPPROTO_TCP && cmsg->cmsg_type == TCP_CM_INQ) {
+			memcpy(inqv, CMSG_DATA(cmsg), sizeof(*inqv));
+			return;
+		}
+	}
+
+	xerror("could not find TCP_CM_INQ cmsg type");
+}
+
+static void process_one_client(int fd, int unixfd)
+{
+	unsigned int tcp_inq;
+	size_t expect_len;
+	char msg_buf[4096];
+	char buf[4096];
+	char tmp[16];
+	struct iovec iov = {
+		.iov_base = buf,
+		.iov_len = 1,
+	};
+	struct msghdr msg = {
+		.msg_iov = &iov,
+		.msg_iovlen = 1,
+		.msg_control = msg_buf,
+		.msg_controllen = sizeof(msg_buf),
+	};
+	ssize_t ret, tot;
+
+	ret = write(unixfd, "xmit", 4);
+	assert(ret == 4);
+
+	ret = read(unixfd, &expect_len, sizeof(expect_len));
+	assert(ret == (ssize_t)sizeof(expect_len));
+
+	if (expect_len > sizeof(buf))
+		xerror("expect len %zu exceeds buffer size", expect_len);
+
+	for (;;) {
+		struct timespec req;
+		unsigned int queued;
+
+		ret = ioctl(fd, FIONREAD, &queued);
+		if (ret < 0)
+			die_perror("FIONREAD");
+		if (queued > expect_len)
+			xerror("FIONREAD returned %u, but only %zu expected\n",
+			       queued, expect_len);
+		if (queued == expect_len)
+			break;
+
+		req.tv_sec = 0;
+		req.tv_nsec = 1000 * 1000ul;
+		nanosleep(&req, NULL);
+	}
+
+	/* read one byte, expect cmsg to return expected - 1 */
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+
+	if (msg.msg_controllen == 0)
+		xerror("msg_controllen is 0");
+
+	get_tcp_inq(&msg, &tcp_inq);
+
+	assert((size_t)tcp_inq == (expect_len - 1));
+
+	iov.iov_len = sizeof(buf);
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+
+	/* should have gotten exact remainder of all pending data */
+	assert(ret == (ssize_t)tcp_inq);
+
+	/* should be 0, all drained */
+	get_tcp_inq(&msg, &tcp_inq);
+	assert(tcp_inq == 0);
+
+	/* request a large swath of data. */
+	ret = write(unixfd, "huge", 4);
+	assert(ret == 4);
+
+	ret = read(unixfd, &expect_len, sizeof(expect_len));
+	assert(ret == (ssize_t)sizeof(expect_len));
+
+	/* peer should send us a few mb of data */
+	if (expect_len <= sizeof(buf))
+		xerror("expect len %zu too small\n", expect_len);
+
+	tot = 0;
+	do {
+		iov.iov_len = sizeof(buf);
+		ret = recvmsg(fd, &msg, 0);
+		if (ret < 0)
+			die_perror("recvmsg");
+
+		tot += ret;
+
+		get_tcp_inq(&msg, &tcp_inq);
+
+		if (tcp_inq > expect_len - tot)
+			xerror("inq %d, remaining %d total_len %d\n",
+			       tcp_inq, expect_len - tot, (int)expect_len);
+
+		assert(tcp_inq <= expect_len - tot);
+	} while ((size_t)tot < expect_len);
+
+	ret = write(unixfd, "shut", 4);
+	assert(ret == 4);
+
+	/* wait for hangup. Should have received one more byte of data. */
+	ret = read(unixfd, tmp, sizeof(tmp));
+	assert(ret == 6);
+	assert(strncmp(tmp, "closed", 6) == 0);
+
+	sleep(1);
+
+	iov.iov_len = 1;
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+	assert(ret == 1);
+
+	get_tcp_inq(&msg, &tcp_inq);
+
+	/* tcp_inq should be 1 due to received fin. */
+	assert(tcp_inq == 1);
+
+	iov.iov_len = 1;
+	ret = recvmsg(fd, &msg, 0);
+	if (ret < 0)
+		die_perror("recvmsg");
+
+	/* expect EOF */
+	assert(ret == 0);
+	get_tcp_inq(&msg, &tcp_inq);
+	assert(tcp_inq == 1);
+
+	close(fd);
+}
+
+static int xaccept(int s)
+{
+	int fd = accept(s, NULL, 0);
+
+	if (fd < 0)
+		die_perror("accept");
+
+	return fd;
+}
+
+static int server(int unixfd)
+{
+	int fd = -1, r, on = 1;
+
+	switch (pf) {
+	case AF_INET:
+		fd = sock_listen_mptcp("127.0.0.1", "15432");
+		break;
+	case AF_INET6:
+		fd = sock_listen_mptcp("::1", "15432");
+		break;
+	default:
+		xerror("Unknown pf %d\n", pf);
+		break;
+	}
+
+	r = write(unixfd, "conn", 4);
+	assert(r == 4);
+
+	alarm(15);
+	r = xaccept(fd);
+
+	if (-1 == setsockopt(r, IPPROTO_TCP, TCP_INQ, &on, sizeof(on)))
+		die_perror("setsockopt");
+
+	process_one_client(r, unixfd);
+
+	return 0;
+}
+
+static int client(int unixfd)
+{
+	int fd = -1;
+
+	alarm(15);
+
+	switch (pf) {
+	case AF_INET:
+		fd = sock_connect_mptcp("127.0.0.1", "15432", proto_tx);
+		break;
+	case AF_INET6:
+		fd = sock_connect_mptcp("::1", "15432", proto_tx);
+		break;
+	default:
+		xerror("Unknown pf %d\n", pf);
+	}
+
+	connect_one_server(fd, unixfd);
+
+	return 0;
+}
+
+static void init_rng(void)
+{
+	int fd = open("/dev/urandom", O_RDONLY);
+	unsigned int foo;
+
+	if (fd > 0) {
+		int ret = read(fd, &foo, sizeof(foo));
+
+		if (ret < 0)
+			srand(fd + foo);
+		close(fd);
+	}
+
+	srand(foo);
+}
+
+static pid_t xfork(void)
+{
+	pid_t p = fork();
+
+	if (p < 0)
+		die_perror("fork");
+	else if (p == 0)
+		init_rng();
+
+	return p;
+}
+
+static int rcheck(int wstatus, const char *what)
+{
+	if (WIFEXITED(wstatus)) {
+		if (WEXITSTATUS(wstatus) == 0)
+			return 0;
+		fprintf(stderr, "%s exited, status=%d\n", what, WEXITSTATUS(wstatus));
+		return WEXITSTATUS(wstatus);
+	} else if (WIFSIGNALED(wstatus)) {
+		xerror("%s killed by signal %d\n", what, WTERMSIG(wstatus));
+	} else if (WIFSTOPPED(wstatus)) {
+		xerror("%s stopped by signal %d\n", what, WSTOPSIG(wstatus));
+	}
+
+	return 111;
+}
+
+int main(int argc, char *argv[])
+{
+	int e1, e2, wstatus;
+	pid_t s, c, ret;
+	int unixfds[2];
+
+	parse_opts(argc, argv);
+
+	e1 = socketpair(AF_UNIX, SOCK_DGRAM, 0, unixfds);
+	if (e1 < 0)
+		die_perror("pipe");
+
+	s = xfork();
+	if (s == 0)
+		return server(unixfds[1]);
+
+	close(unixfds[1]);
+
+	/* wait until server bound a socket */
+	e1 = read(unixfds[0], &e1, 4);
+	assert(e1 == 4);
+
+	c = xfork();
+	if (c == 0)
+		return client(unixfds[0]);
+
+	close(unixfds[0]);
+
+	ret = waitpid(s, &wstatus, 0);
+	if (ret == -1)
+		die_perror("waitpid");
+	e1 = rcheck(wstatus, "server");
+	ret = waitpid(c, &wstatus, 0);
+	if (ret == -1)
+		die_perror("waitpid");
+	e2 = rcheck(wstatus, "client");
+
+	return e1 ? e1 : e2;
+}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
index c8c364369599..0879da915014 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
@@ -279,6 +279,45 @@ run_tests()
 	fi
 }
 
+do_tcpinq_test()
+{
+	ip netns exec "$ns1" ./mptcp_inq "$@"
+	lret=$?
+	if [ $lret -ne 0 ];then
+		ret=$lret
+		echo "FAIL: mptcp_inq $@" 1>&2
+		return $lret
+	fi
+
+	echo "PASS: TCP_INQ cmsg/ioctl $@"
+	return $lret
+}
+
+do_tcpinq_tests()
+{
+	local lret=0
+
+	ip netns exec "$ns1" iptables -F
+	ip netns exec "$ns1" ip6tables -F
+
+	for args in "-t tcp" "-r tcp"; do
+		do_tcpinq_test $args
+		lret=$?
+		if [ $lret -ne 0 ] ; then
+			return $lret
+		fi
+		do_tcpinq_test -6 $args
+		lret=$?
+		if [ $lret -ne 0 ] ; then
+			return $lret
+		fi
+	done
+
+	do_tcpinq_test -r tcp -t tcp
+
+	return $?
+}
+
 sin=$(mktemp)
 sout=$(mktemp)
 cin=$(mktemp)
@@ -300,4 +339,5 @@ if [ $ret -eq 0 ];then
 	echo "PASS: SOL_MPTCP getsockopt has expected information"
 fi
 
+do_tcpinq_tests
 exit $ret
-- 
2.34.1

[PATCH net-next 05/10] mptcp: allow changing the "backup" bit by endpoint id

[Mat Martineau]

From: Davide Caratti <dcaratti@redhat.com>

a non-zero 'id' is sufficient to identify MPTCP endpoints: allow changing
the value of 'backup' bit by simply specifying the endpoint id.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/158
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/pm_netlink.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 7b96be1e9f14..4ff8d55cbe82 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -1702,22 +1702,28 @@ static int mptcp_nl_addr_backup(struct net *net,
 
 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
 {
+	struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry;
 	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
 	struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
-	struct mptcp_pm_addr_entry addr, *entry;
 	struct net *net = sock_net(skb->sk);
-	u8 bkup = 0;
+	u8 bkup = 0, lookup_by_id = 0;
 	int ret;
 
-	ret = mptcp_pm_parse_addr(attr, info, true, &addr);
+	ret = mptcp_pm_parse_addr(attr, info, false, &addr);
 	if (ret < 0)
 		return ret;
 
 	if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
 		bkup = 1;
+	if (addr.addr.family == AF_UNSPEC) {
+		lookup_by_id = 1;
+		if (!addr.addr.id)
+			return -EOPNOTSUPP;
+	}
 
 	list_for_each_entry(entry, &pernet->local_addr_list, list) {
-		if (addresses_equal(&entry->addr, &addr.addr, true)) {
+		if ((!lookup_by_id && addresses_equal(&entry->addr, &addr.addr, true)) ||
+		    (lookup_by_id && entry->addr.id == addr.addr.id)) {
 			mptcp_nl_addr_backup(net, &entry->addr, bkup);
 
 			if (bkup)
-- 
2.34.1

[PATCH net-next 06/10] mptcp: getsockopt: add support for IP_TOS

[Mat Martineau]

From: Florian Westphal <fw@strlen.de>

earlier patch added IP_TOS setsockopt support, this allows to get
the value set by earlier setsockopt.

Extends mptcp_put_int_option to handle u8 input/output by
adding required cast.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/sockopt.c | 36 ++++++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 6 deletions(-)

diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 11cda8629993..44e0a37c567c 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -1053,15 +1053,24 @@ static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
 
 	if (get_user(len, optlen))
 		return -EFAULT;
-
-	len = min_t(unsigned int, len, sizeof(int));
 	if (len < 0)
 		return -EINVAL;
 
-	if (put_user(len, optlen))
-		return -EFAULT;
-	if (copy_to_user(optval, &val, len))
-		return -EFAULT;
+	if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
+		unsigned char ucval = (unsigned char)val;
+
+		len = 1;
+		if (put_user(len, optlen))
+			return -EFAULT;
+		if (copy_to_user(optval, &ucval, 1))
+			return -EFAULT;
+	} else {
+		len = min_t(unsigned int, len, sizeof(int));
+		if (put_user(len, optlen))
+			return -EFAULT;
+		if (copy_to_user(optval, &val, len))
+			return -EFAULT;
+	}
 
 	return 0;
 }
@@ -1082,6 +1091,19 @@ static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 	return -EOPNOTSUPP;
 }
 
+static int mptcp_getsockopt_v4(struct mptcp_sock *msk, int optname,
+			       char __user *optval, int __user *optlen)
+{
+	struct sock *sk = (void *)msk;
+
+	switch (optname) {
+	case IP_TOS:
+		return mptcp_put_int_option(msk, optval, optlen, inet_sk(sk)->tos);
+	}
+
+	return -EOPNOTSUPP;
+}
+
 static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname,
 				      char __user *optval, int __user *optlen)
 {
@@ -1117,6 +1139,8 @@ int mptcp_getsockopt(struct sock *sk, int level, int optname,
 	if (ssk)
 		return tcp_getsockopt(ssk, level, optname, optval, option);
 
+	if (level == SOL_IP)
+		return mptcp_getsockopt_v4(msk, optname, optval, option);
 	if (level == SOL_TCP)
 		return mptcp_getsockopt_sol_tcp(msk, optname, optval, option);
 	if (level == SOL_MPTCP)
-- 
2.34.1

Re: [PATCH net-next 06/10] mptcp: getsockopt: add support for IP_TOS

[Jakub Kicinski]

On Fri,  3 Dec 2021 14:35:37 -0800 Mat Martineau wrote:
>  	if (get_user(len, optlen))
>  		return -EFAULT;
> -
> -	len = min_t(unsigned int, len, sizeof(int));

Ah, there's the min() gone. Okay.

>  	if (len < 0)
>  		return -EINVAL;

[PATCH net-next 07/10] selftests: mptcp: check IP_TOS in/out are the same

[Mat Martineau]

From: Florian Westphal <fw@strlen.de>

Check that getsockopt(IP_TOS) returns what setsockopt(IP_TOS) did set
right before.

Also check that socklen_t == 0 and -1 input values match those
of normal tcp sockets.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 .../selftests/net/mptcp/mptcp_sockopt.c       | 63 +++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
index 417b11cafafe..ac9a4d9c1764 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
@@ -4,6 +4,7 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <limits.h>
 #include <string.h>
 #include <stdarg.h>
@@ -13,6 +14,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <strings.h>
+#include <time.h>
 #include <unistd.h>
 
 #include <sys/socket.h>
@@ -594,6 +596,44 @@ static int server(int pipefd)
 	return 0;
 }
 
+static void test_ip_tos_sockopt(int fd)
+{
+	uint8_t tos_in, tos_out;
+	socklen_t s;
+	int r;
+
+	tos_in = rand() & 0xfc;
+	r = setsockopt(fd, SOL_IP, IP_TOS, &tos_in, sizeof(tos_out));
+	if (r != 0)
+		die_perror("setsockopt IP_TOS");
+
+	tos_out = 0;
+	s = sizeof(tos_out);
+	r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s);
+	if (r != 0)
+		die_perror("getsockopt IP_TOS");
+
+	if (tos_in != tos_out)
+		xerror("tos %x != %x socklen_t %d\n", tos_in, tos_out, s);
+
+	if (s != 1)
+		xerror("tos should be 1 byte");
+
+	s = 0;
+	r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s);
+	if (r != 0)
+		die_perror("getsockopt IP_TOS 0");
+	if (s != 0)
+		xerror("expect socklen_t == 0");
+
+	s = -1;
+	r = getsockopt(fd, SOL_IP, IP_TOS, &tos_out, &s);
+	if (r != -1 && errno != EINVAL)
+		die_perror("getsockopt IP_TOS did not indicate -EINVAL");
+	if (s != -1)
+		xerror("expect socklen_t == -1");
+}
+
 static int client(int pipefd)
 {
 	int fd = -1;
@@ -611,6 +651,8 @@ static int client(int pipefd)
 		xerror("Unknown pf %d\n", pf);
 	}
 
+	test_ip_tos_sockopt(fd);
+
 	connect_one_server(fd, pipefd);
 
 	return 0;
@@ -642,6 +684,25 @@ static int rcheck(int wstatus, const char *what)
 	return 111;
 }
 
+static void init_rng(void)
+{
+	int fd = open("/dev/urandom", O_RDONLY);
+
+	if (fd >= 0) {
+		unsigned int foo;
+		ssize_t ret;
+
+		/* can't fail */
+		ret = read(fd, &foo, sizeof(foo));
+		assert(ret == sizeof(foo));
+
+		close(fd);
+		srand(foo);
+	} else {
+		srand(time(NULL));
+	}
+}
+
 int main(int argc, char *argv[])
 {
 	int e1, e2, wstatus;
@@ -650,6 +711,8 @@ int main(int argc, char *argv[])
 
 	parse_opts(argc, argv);
 
+	init_rng();
+
 	e1 = pipe(pipefds);
 	if (e1 < 0)
 		die_perror("pipe");
-- 
2.34.1

[PATCH net-next 08/10] tcp: expose __tcp_sock_set_cork and __tcp_sock_set_nodelay

[Mat Martineau]

From: Maxim Galaganov <max@internet.ru>

Expose __tcp_sock_set_cork() and __tcp_sock_set_nodelay() for use in
MPTCP setsockopt code -- namely for syncing MPTCP socket options with
subflows inside sync_socket_options() while already holding the subflow
socket lock.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Maxim Galaganov <max@internet.ru>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 include/linux/tcp.h | 2 ++
 net/ipv4/tcp.c      | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 48d8a363319e..78b91bb92f0d 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -512,11 +512,13 @@ static inline u16 tcp_mss_clamp(const struct tcp_sock *tp, u16 mss)
 int tcp_skb_shift(struct sk_buff *to, struct sk_buff *from, int pcount,
 		  int shiftlen);
 
+void __tcp_sock_set_cork(struct sock *sk, bool on);
 void tcp_sock_set_cork(struct sock *sk, bool on);
 int tcp_sock_set_keepcnt(struct sock *sk, int val);
 int tcp_sock_set_keepidle_locked(struct sock *sk, int val);
 int tcp_sock_set_keepidle(struct sock *sk, int val);
 int tcp_sock_set_keepintvl(struct sock *sk, int val);
+void __tcp_sock_set_nodelay(struct sock *sk, bool on);
 void tcp_sock_set_nodelay(struct sock *sk);
 void tcp_sock_set_quickack(struct sock *sk, int val);
 int tcp_sock_set_syncnt(struct sock *sk, int val);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 6ab82e1a1d41..20054618c87e 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3207,7 +3207,7 @@ static void tcp_enable_tx_delay(void)
  * TCP_CORK can be set together with TCP_NODELAY and it is stronger than
  * TCP_NODELAY.
  */
-static void __tcp_sock_set_cork(struct sock *sk, bool on)
+void __tcp_sock_set_cork(struct sock *sk, bool on)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
@@ -3235,7 +3235,7 @@ EXPORT_SYMBOL(tcp_sock_set_cork);
  * However, when TCP_NODELAY is set we make an explicit push, which overrides
  * even TCP_CORK for currently queued segments.
  */
-static void __tcp_sock_set_nodelay(struct sock *sk, bool on)
+void __tcp_sock_set_nodelay(struct sock *sk, bool on)
 {
 	if (on) {
 		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF|TCP_NAGLE_PUSH;
-- 
2.34.1

[PATCH net-next 09/10] mptcp: expose mptcp_check_and_set_pending

[Mat Martineau]

From: Maxim Galaganov <max@internet.ru>

Expose the mptcp_check_and_set_pending() function for use inside MPTCP
sockopt code. The next patch will call it when TCP_CORK is cleared or
TCP_NODELAY is set on the MPTCP socket in order to push pending data
from mptcp_release_cb().

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Maxim Galaganov <max@internet.ru>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/protocol.c | 2 +-
 net/mptcp/protocol.h | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 943f74e804bd..f124cca125d2 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1502,7 +1502,7 @@ static void mptcp_update_post_push(struct mptcp_sock *msk,
 		msk->snd_nxt = snd_nxt_new;
 }
 
-static void mptcp_check_and_set_pending(struct sock *sk)
+void mptcp_check_and_set_pending(struct sock *sk)
 {
 	if (mptcp_send_head(sk) &&
 	    !test_bit(MPTCP_PUSH_PENDING, &mptcp_sk(sk)->flags))
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index bb51fa7f5566..147b22da41ca 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -555,6 +555,7 @@ unsigned int mptcp_stale_loss_cnt(const struct net *net);
 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow,
 				     struct mptcp_options_received *mp_opt);
 bool __mptcp_retransmit_pending_data(struct sock *sk);
+void mptcp_check_and_set_pending(struct sock *sk);
 void __mptcp_push_pending(struct sock *sk, unsigned int flags);
 bool mptcp_subflow_data_available(struct sock *sk);
 void __init mptcp_subflow_init(void);
-- 
2.34.1

[PATCH net-next 10/10] mptcp: support TCP_CORK and TCP_NODELAY

[Mat Martineau]

From: Maxim Galaganov <max@internet.ru>

First, add cork and nodelay fields to the mptcp_sock structure
so they can be used in sync_socket_options(), and fill them on setsockopt
while holding the msk socket lock.

Then, on setsockopt set proper tcp_sk(ssk)->nonagle values for subflows
by calling __tcp_sock_set_cork() or __tcp_sock_set_nodelay() on the ssk
while holding the ssk socket lock.

tcp_push_pending_frames() will be invoked on the ssk if a cork was cleared
or nodelay was set. Also set MPTCP_PUSH_PENDING bit by calling
mptcp_check_and_set_pending(). This will lead to __mptcp_push_pending()
being called inside mptcp_release_cb() with new tcp_sk(ssk)->nonagle.

Also add getsockopt support for TCP_CORK and TCP_NODELAY.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Maxim Galaganov <max@internet.ru>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/protocol.h |  4 ++-
 net/mptcp/sockopt.c  | 70 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 147b22da41ca..e1469155fb15 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -249,7 +249,9 @@ struct mptcp_sock {
 	bool		rcv_fastclose;
 	bool		use_64bit_ack; /* Set when we received a 64-bit DSN */
 	bool		csum_enabled;
-	u8		recvmsg_inq:1;
+	u8		recvmsg_inq:1,
+			cork:1,
+			nodelay:1;
 	spinlock_t	join_list_lock;
 	struct work_struct work;
 	struct sk_buff  *ooo_last_skb;
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 44e0a37c567c..3c3db22fd36a 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -616,6 +616,66 @@ static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t
 	return ret;
 }
 
+static int mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, sockptr_t optval,
+					 unsigned int optlen)
+{
+	struct mptcp_subflow_context *subflow;
+	struct sock *sk = (struct sock *)msk;
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (copy_from_sockptr(&val, optval, sizeof(val)))
+		return -EFAULT;
+
+	lock_sock(sk);
+	sockopt_seq_inc(msk);
+	msk->cork = !!val;
+	mptcp_for_each_subflow(msk, subflow) {
+		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
+
+		lock_sock(ssk);
+		__tcp_sock_set_cork(ssk, !!val);
+		release_sock(ssk);
+	}
+	if (!val)
+		mptcp_check_and_set_pending(sk);
+	release_sock(sk);
+
+	return 0;
+}
+
+static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval,
+					    unsigned int optlen)
+{
+	struct mptcp_subflow_context *subflow;
+	struct sock *sk = (struct sock *)msk;
+	int val;
+
+	if (optlen < sizeof(int))
+		return -EINVAL;
+
+	if (copy_from_sockptr(&val, optval, sizeof(val)))
+		return -EFAULT;
+
+	lock_sock(sk);
+	sockopt_seq_inc(msk);
+	msk->nodelay = !!val;
+	mptcp_for_each_subflow(msk, subflow) {
+		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
+
+		lock_sock(ssk);
+		__tcp_sock_set_nodelay(ssk, !!val);
+		release_sock(ssk);
+	}
+	if (val)
+		mptcp_check_and_set_pending(sk);
+	release_sock(sk);
+
+	return 0;
+}
+
 static int mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock *msk, int optname,
 						   sockptr_t optval, unsigned int optlen)
 {
@@ -717,6 +777,10 @@ static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 		return -EOPNOTSUPP;
 	case TCP_CONGESTION:
 		return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen);
+	case TCP_CORK:
+		return mptcp_setsockopt_sol_tcp_cork(msk, optval, optlen);
+	case TCP_NODELAY:
+		return mptcp_setsockopt_sol_tcp_nodelay(msk, optval, optlen);
 	}
 
 	return -EOPNOTSUPP;
@@ -1087,6 +1151,10 @@ static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 						      optval, optlen);
 	case TCP_INQ:
 		return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq);
+	case TCP_CORK:
+		return mptcp_put_int_option(msk, optval, optlen, msk->cork);
+	case TCP_NODELAY:
+		return mptcp_put_int_option(msk, optval, optlen, msk->nodelay);
 	}
 	return -EOPNOTSUPP;
 }
@@ -1189,6 +1257,8 @@ static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk)
 
 	if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops)
 		tcp_set_congestion_control(ssk, msk->ca_name, false, true);
+	__tcp_sock_set_cork(ssk, !!msk->cork);
+	__tcp_sock_set_nodelay(ssk, !!msk->nodelay);
 
 	inet_sk(ssk)->transparent = inet_sk(sk)->transparent;
 	inet_sk(ssk)->freebind = inet_sk(sk)->freebind;
-- 
2.34.1

Re: [PATCH net-next 10/10] mptcp: support TCP_CORK and TCP_NODELAY

[Jakub Kicinski]

On Fri,  3 Dec 2021 14:35:41 -0800 Mat Martineau wrote:
> +static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval,
> +					    unsigned int optlen)
> +{
> +	struct mptcp_subflow_context *subflow;
> +	struct sock *sk = (struct sock *)msk;
> +	int val;
> +
> +	if (optlen < sizeof(int))
> +		return -EINVAL;
> +
> +	if (copy_from_sockptr(&val, optval, sizeof(val)))
> +		return -EFAULT;

Should we check that optval is not larger than sizeof(int) or if it is
that the rest of the buffer is zero? Or for the old school options we
should stick to the old school behavior?

Re: [PATCH net-next 10/10] mptcp: support TCP_CORK and TCP_NODELAY

[Florian Westphal]

Jakub Kicinski <kuba@kernel.org> wrote:
> On Fri,  3 Dec 2021 14:35:41 -0800 Mat Martineau wrote:
> > +static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval,
> > +					    unsigned int optlen)
> > +{
> > +	struct mptcp_subflow_context *subflow;
> > +	struct sock *sk = (struct sock *)msk;
> > +	int val;
> > +
> > +	if (optlen < sizeof(int))
> > +		return -EINVAL;
> > +
> > +	if (copy_from_sockptr(&val, optval, sizeof(val)))
> > +		return -EFAULT;
> 
> Should we check that optval is not larger than sizeof(int) or if it is
> that the rest of the buffer is zero? Or for the old school options we
> should stick to the old school behavior?

My intent was to stick to tcp behaviour, i.e. no check on > sizeof(int)
or on "extra buffer" content.

Re: [PATCH net-next 10/10] mptcp: support TCP_CORK and TCP_NODELAY

[Paolo Abeni]

On Mon, 2021-12-06 at 17:30 -0800, Jakub Kicinski wrote:
> On Fri,  3 Dec 2021 14:35:41 -0800 Mat Martineau wrote:
> > +static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval,
> > +					    unsigned int optlen)
> > +{
> > +	struct mptcp_subflow_context *subflow;
> > +	struct sock *sk = (struct sock *)msk;
> > +	int val;
> > +
> > +	if (optlen < sizeof(int))
> > +		return -EINVAL;
> > +
> > +	if (copy_from_sockptr(&val, optval, sizeof(val)))
> > +		return -EFAULT;
> 
> Should we check that optval is not larger than sizeof(int) or if it is
> that the rest of the buffer is zero? Or for the old school options we
> should stick to the old school behavior?

I think it's useful if we keep the MPTCP socket options binary API as
close as possible to the plain TCP ones: that allows for seamless
switching existing TCP application to MPTCP with no code changes.

Old school, please ;)

Cheers,

Paolo 

Re: [PATCH net-next 00/10] mptcp: New features for MPTCP sockets and netlink PM

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net-next.git (master)
by Jakub Kicinski <kuba@kernel.org>:

On Fri,  3 Dec 2021 14:35:31 -0800 you wrote:
> This collection of patches adds MPTCP socket support for a few socket
> options, ioctls, and one ancillary data type (specifics for each are
> listed below). There's also a patch modifying the netlink MPTCP path
> manager API to allow setting the backup flag on a configured interface
> using the endpoint ID instead of the full IP address.
> 
> Patches 1 & 2: TCP_INQ cmsg and selftests.
> 
> [...]

Here is the summary with links:
  - [net-next,01/10] mptcp: add TCP_INQ cmsg support
    https://git.kernel.org/netdev/net-next/c/2c9e77659a0c
  - [net-next,02/10] selftests: mptcp: add TCP_INQ support
    https://git.kernel.org/netdev/net-next/c/5cbd886ce2a9
  - [net-next,03/10] mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls
    https://git.kernel.org/netdev/net-next/c/644807e3e462
  - [net-next,04/10] selftests: mptcp: add inq test case
    https://git.kernel.org/netdev/net-next/c/b51880568f20
  - [net-next,05/10] mptcp: allow changing the "backup" bit by endpoint id
    https://git.kernel.org/netdev/net-next/c/602837e8479d
  - [net-next,06/10] mptcp: getsockopt: add support for IP_TOS
    https://git.kernel.org/netdev/net-next/c/3b1e21eb60e8
  - [net-next,07/10] selftests: mptcp: check IP_TOS in/out are the same
    https://git.kernel.org/netdev/net-next/c/edb596e80cee
  - [net-next,08/10] tcp: expose __tcp_sock_set_cork and __tcp_sock_set_nodelay
    https://git.kernel.org/netdev/net-next/c/6fadaa565882
  - [net-next,09/10] mptcp: expose mptcp_check_and_set_pending
    https://git.kernel.org/netdev/net-next/c/8b38217a2a98
  - [net-next,10/10] mptcp: support TCP_CORK and TCP_NODELAY
    https://git.kernel.org/netdev/net-next/c/4f6e14bd19d6

You are awesome, thank you!
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