Index: head/stand/libsa/net.h
===================================================================
--- head/stand/libsa/net.h
+++ head/stand/libsa/net.h
@@ -61,6 +61,20 @@
 #define MAXTMO 120	/* seconds */
 #define MINTMO 2	/* seconds */
 
+/*
+ * Maximum wait time for sending and receiving before we give up and timeout.
+ * If set to 0, operations will eventually timeout completely, but send/recv
+ * timeouts must progress exponentially from MINTMO to MAXTMO before final
+ * timeout is hit.
+ */
+#ifndef MAXWAIT
+#define MAXWAIT 0	/* seconds */
+#endif
+
+#if MAXWAIT < 0
+#error MAXWAIT must not be a negative number
+#endif
+
 #define FNAME_SIZE 128
 #define	IFNAME_SIZE 16
 #define RECV_SIZE 1536	/* XXX delete this */
Index: head/stand/libsa/net.c
===================================================================
--- head/stand/libsa/net.c
+++ head/stand/libsa/net.c
@@ -77,6 +77,7 @@
 {
 	ssize_t cc;
 	time_t t, tmo, tlast;
+	time_t tref;
 	long tleft;
 
 #ifdef NET_DEBUG
@@ -87,13 +88,14 @@
 	tmo = MINTMO;
 	tlast = 0;
 	tleft = 0;
+	tref = getsecs();
 	t = getsecs();
 	for (;;) {
+		if (MAXWAIT > 0 && (getsecs() - tref) >= MAXWAIT) {
+			errno = ETIMEDOUT;
+			return -1;
+		}
 		if (tleft <= 0) {
-			if (tmo >= MAXTMO) {
-				errno = ETIMEDOUT;
-				return -1;
-			}
 			cc = (*sproc)(d, sbuf, ssize);
 			if (cc != -1 && cc < ssize)
 				panic("sendrecv: short write! (%zd < %zd)",