conf, tcp, udp: Exit if we fail to bind sockets for all given ports

passt supports ranges of forwarded ports as well as 'all' for TCP and
UDP, so it might be convenient to proceed if we fail to bind only
some of the desired ports.

But if we fail to bind even a single port for a given specification,
we're clearly, unexpectedly, conflicting with another network
service. In that case, report failure and exit.

Reported-by: Yalan Zhang <yalzhang@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 13 insertions, 3 deletions

diff --git a/udp.c b/udp.c
index 2e9b7e6..c913d27 100644
--- a/udp.c
+++ b/udp.c
@@ -955,12 +955,14 @@ int udp_tap_handler(struct ctx *c, int af, const void *addr,
  * @addr:	Pointer to address for binding, NULL if not configured
  * @ifname:	Name of interface to bind to, NULL if not configured
  * @port:	Port, host order
+ *
+ * Return: 0 on (partial) success, -1 on (complete) failure
  */
-void udp_sock_init(const struct ctx *c, int ns, sa_family_t af,
-		   const void *addr, const char *ifname, in_port_t port)
+int udp_sock_init(const struct ctx *c, int ns, sa_family_t af,
+		  const void *addr, const char *ifname, in_port_t port)
 {
 	union udp_epoll_ref uref = { .u32 = 0 };
-	int s;
+	int s, ret = 0;
 
 	if (ns) {
 		uref.udp.port = (in_port_t)(port +
@@ -989,6 +991,9 @@ void udp_sock_init(const struct ctx *c, int ns, sa_family_t af,
 				    ifname, port, uref.u32);
 			udp_splice_ns[V4][port].sock = s;
 		}
+
+		if (s < 0)
+			ret = -1;
 	}
 
 	if ((af == AF_INET6 || af == AF_UNSPEC) && c->ifi6) {
@@ -1009,7 +1014,12 @@ void udp_sock_init(const struct ctx *c, int ns, sa_family_t af,
 				    ifname, port, uref.u32);
 			udp_splice_ns[V6][port].sock = s;
 		}
+
+		if (s < 0)
+			ret = -1;
 	}
+
+	return ret;
 }
 
 /**