OS-4647 lx fails to mount nfs share - Transport endpoint is already connected

7 files changed, 53 insertions, 4 deletions

diff --git a/usr/src/cmd/truss/print.c b/usr/src/cmd/truss/print.c
index 66a9d7387e..2b59676e30 100644
--- a/usr/src/cmd/truss/print.c
+++ b/usr/src/cmd/truss/print.c
@@ -2001,6 +2001,7 @@ udp_optname(private_t *pri, long val)
 	case UDP_RCVHDR:		return ("UDP_RCVHDR");
 	case UDP_NAT_T_ENDPOINT:	return ("UDP_NAT_T_ENDPOINT");
 	case UDP_SRCPORT_HASH:		return ("UDP_SRCPORT_HASH");
+	case UDP_SND_TO_CONNECTED:	return ("UDP_SND_TO_CONNECTED");
 
 	default:			(void) snprintf(pri->code_buf,
 					    sizeof (pri->code_buf), "0x%lx",
diff --git a/usr/src/lib/brand/lx/lx_brand/common/socket.c b/usr/src/lib/brand/lx/lx_brand/common/socket.c
index 264d7ad345..d5f7161524 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/socket.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/socket.c
@@ -1090,6 +1090,10 @@ lx_setsockopt(int sockfd, int level, int optname, void *optval, int optlen)
 		    strcmp(lx_cmd_name, "traceroute") == 0)
 			return (0);
 
+		if (optname == LX_IP_RECVERR &&
+		    strcmp(lx_cmd_name, "mount.nfs") == 0)
+			return (0);
+
 		if (optname == LX_IP_MTU_DISCOVER) {
 			/*
 			 * Native programs such as traceroute use IP_DONTFRAG
diff --git a/usr/src/uts/common/brand/lx/syscall/lx_socket.c b/usr/src/uts/common/brand/lx/syscall/lx_socket.c
index 1b4b24aa86..023c61b082 100644
--- a/usr/src/uts/common/brand/lx/syscall/lx_socket.c
+++ b/usr/src/uts/common/brand/lx/syscall/lx_socket.c
@@ -48,6 +48,8 @@
 #include <netpacket/packet.h>
 #include <sockcommon.h>
 #include <socktpi_impl.h>
+#include <netinet/udp.h>
+#include <sys/sdt.h>
 
 #include <sys/lx_brand.h>
 #include <sys/lx_socket.h>
@@ -1177,7 +1179,7 @@ lx_connect(long sock, uintptr_t name, socklen_t namelen)
 	}
 
 	/*
-	 * Ensure the name is size appropriately before we alloc memory and
+	 * Ensure the name is sized appropriately before we alloc memory and
 	 * copy it in from userspace.  We need at least the address family to
 	 * make later sizing decisions.
 	 */
@@ -1213,6 +1215,21 @@ lx_connect(long sock, uintptr_t name, socklen_t namelen)
 		mutex_exit(&sad->lxsad_lock);
 	}
 
+	/*
+	 * When connecting to a UDP socket, configure it so that future
+	 * sendto/sendmsg operations are allowed to specify a destination
+	 * address. See the Posix spec. for sendto(2). Linux allows this while
+	 * illumos would return EISCONN if the option is not set.
+	 */
+	if (error == 0 && so->so_protocol == IPPROTO_UDP &&
+	    (so->so_family == AF_INET || so->so_family == AF_INET6)) {
+		int val = 1;
+
+		DTRACE_PROBE(lx__connect__udp);
+		(void) socket_setsockopt(so, IPPROTO_UDP, UDP_SND_TO_CONNECTED,
+		    &val, sizeof (val), CRED());
+	}
+
 	releasef(sock);
 
 	if (addr != NULL) {
diff --git a/usr/src/uts/common/inet/udp/udp.c b/usr/src/uts/common/inet/udp/udp.c
index eec3beddd2..7f468a190e 100644
--- a/usr/src/uts/common/inet/udp/udp.c
+++ b/usr/src/uts/common/inet/udp/udp.c
@@ -1673,6 +1673,11 @@ udp_opt_get(conn_t *connp, t_scalar_t level, t_scalar_t name,
 			*i1 = udp->udp_vxlanhash;
 			mutex_exit(&connp->conn_lock);
 			return (sizeof (int));
+		case UDP_SND_TO_CONNECTED:
+			mutex_enter(&connp->conn_lock);
+			*i1 = udp->udp_snd_to_conn ? 1 : 0;
+			mutex_exit(&connp->conn_lock);
+			return (sizeof (int));
 		}
 	}
 	mutex_enter(&connp->conn_lock);
@@ -1828,6 +1833,11 @@ udp_do_opt_set(conn_opt_arg_t *coa, int level, int name,
 			}
 			/* Fully handled this option. */
 			return (0);
+		case UDP_SND_TO_CONNECTED:
+			mutex_enter(&connp->conn_lock);
+			udp->udp_snd_to_conn = onoff;
+			mutex_exit(&connp->conn_lock);
+			return (0);
 		}
 		break;
 	}
@@ -6051,6 +6061,7 @@ udp_send(sock_lower_handle_t proto_handle, mblk_t *mp, struct nmsghdr *msg,
 	ushort_t	ipversion;
 	pid_t		pid = curproc->p_pid;
 	ip_xmit_attr_t	*ixa;
+	boolean_t	snd_to_conn;
 
 	ASSERT(DB_TYPE(mp) == M_DATA);
 
@@ -6088,10 +6099,21 @@ udp_send(sock_lower_handle_t proto_handle, mblk_t *mp, struct nmsghdr *msg,
 		else
 			return (error);
 	}
-	if (udp->udp_state == TS_DATA_XFER) {
+
+	/*
+	 * Check if we're allowed to send to a connection on which we've
+	 * already called 'connect'. The posix spec. allows both behaviors but
+	 * historically we've returned an error if already connected. The
+	 * client can allow this via a sockopt.
+	 */
+	mutex_enter(&connp->conn_lock);
+	snd_to_conn = (udp->udp_snd_to_conn != 0);
+	mutex_exit(&connp->conn_lock);
+	if (udp->udp_state == TS_DATA_XFER && !snd_to_conn) {
 		UDPS_BUMP_MIB(us, udpOutErrors);
 		return (EISCONN);
 	}
+
 	error = proto_verify_ip_addr(connp->conn_family,
 	    (struct sockaddr *)msg->msg_name, msg->msg_namelen);
 	if (error != 0) {
diff --git a/usr/src/uts/common/inet/udp/udp_opt_data.c b/usr/src/uts/common/inet/udp/udp_opt_data.c
index fec3dec4c9..847e2cdde6 100644
--- a/usr/src/uts/common/inet/udp/udp_opt_data.c
+++ b/usr/src/uts/common/inet/udp/udp_opt_data.c
@@ -293,7 +293,9 @@ opdes_t	udp_opt_arr[] = {
 	},
 { UDP_NAT_T_ENDPOINT, IPPROTO_UDP, OA_RW, OA_RW, OP_PRIVPORT, 0, sizeof (int),
 	0 },
-{ UDP_SRCPORT_HASH, IPPROTO_UDP, OA_R, OA_RW, OP_CONFIG, 0, sizeof (int), 0 }
+{ UDP_SRCPORT_HASH, IPPROTO_UDP, OA_R, OA_RW, OP_CONFIG, 0, sizeof (int), 0 },
+{ UDP_SND_TO_CONNECTED, IPPROTO_UDP, OA_R, OA_RW, OP_CONFIG, 0, sizeof (int),
+	0 }
 };
 
 /*
diff --git a/usr/src/uts/common/inet/udp_impl.h b/usr/src/uts/common/inet/udp_impl.h
index 3b07abc309..ebba10c0f7 100644
--- a/usr/src/uts/common/inet/udp_impl.h
+++ b/usr/src/uts/common/inet/udp_impl.h
@@ -182,8 +182,9 @@ typedef	struct udp_s {
 		udp_vxlanhash: 1,	/* UDP_SRCPORT_HASH option */
 					/* Because there's only VXLAN, cheat */
 					/* and only use a single bit */
+		udp_snd_to_conn: 1,	/* UDP_SND_TO_CONNECTED option */
 
-		udp_pad_to_bit_31 : 28;
+		udp_pad_to_bit_31 : 27;
 
 	/* Following 2 fields protected by the uf_lock */
 	struct udp_s	*udp_bind_hash; /* Bind hash chain */
diff --git a/usr/src/uts/common/netinet/udp.h b/usr/src/uts/common/netinet/udp.h
index fb9f8a0976..74cff75d43 100644
--- a/usr/src/uts/common/netinet/udp.h
+++ b/usr/src/uts/common/netinet/udp.h
@@ -1,6 +1,7 @@
 /*
  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
+ * Copyright 2015 Joyent, Inc.
  */
 
 /*
@@ -34,6 +35,7 @@ struct udphdr {
 #define	UDP_RCVHDR		0x0102		/* for internal use only */
 #define	UDP_NAT_T_ENDPOINT	0x0103		/* for internal use only */
 #define	UDP_SRCPORT_HASH	0x0104		/* for internal use only */
+#define	UDP_SND_TO_CONNECTED	0x0105		/* for internal use only */
 
 /*
  * Hash definitions for UDP_SRCPORT_HASH that effectively tell UDP how to go