diff --git a/src/lib/net/address.c b/src/lib/net/address.c
index 26b155bc4c..085eb8c458 100644
--- a/src/lib/net/address.c
+++ b/src/lib/net/address.c
@@ -2005,20 +2005,15 @@ parse_port_range(const char *port, uint16_t *port_min_out,
     char *endptr = NULL;
     port_min = (int)tor_parse_long(port, 10, 0, 65535, &ok, &endptr);
     if (!ok) {
-      log_warn(LD_GENERAL,
-               "Malformed port %s on address range; rejecting.",
-               escaped(port));
-      return -1;
-    } else if (endptr && *endptr == '-') {
+      goto malformed_port;
+    } else if (endptr && *endptr != '\0') {
+      if (*endptr != '-')
+        goto malformed_port;
       port = endptr+1;
       endptr = NULL;
       port_max = (int)tor_parse_long(port, 10, 1, 65535, &ok, &endptr);
-      if (!ok) {
-        log_warn(LD_GENERAL,
-                 "Malformed port %s on address range; rejecting.",
-                 escaped(port));
-        return -1;
-      }
+      if (!ok)
+        goto malformed_port;
     } else {
       port_max = port_min;
     }
@@ -2037,6 +2032,11 @@ parse_port_range(const char *port, uint16_t *port_min_out,
   *port_max_out = (uint16_t) port_max;
 
   return 0;
+ malformed_port:
+  log_warn(LD_GENERAL,
+           "Malformed port %s on address range; rejecting.",
+           escaped(port));
+  return -1;
 }
 
 /** Given a host-order <b>addr</b>, call tor_inet_ntop() on it
diff --git a/src/test/test_address.c b/src/test/test_address.c
index 9c1415419c..015ca0807c 100644
--- a/src/test/test_address.c
+++ b/src/test/test_address.c
@@ -1326,6 +1326,42 @@ test_address_dirserv_router_addr_private(void *opt_dir_allow_private)
   UNMOCK(get_options);
 }
 
+static void
+test_address_parse_port_range(void *arg)
+{
+  int ret;
+  uint16_t min_out = 0;
+  uint16_t max_out = 0;
+
+  (void) arg;
+
+  /* Invalid. */
+  ret = parse_port_range("0x00", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, -1);
+  ret = parse_port_range("0x01", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, -1);
+  ret = parse_port_range("1817161", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, -1);
+  ret = parse_port_range("65536", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, -1);
+  ret = parse_port_range("1-65536", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, -1);
+
+  /* Valid. */
+  ret = parse_port_range("65535", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, 0);
+  tt_int_op(min_out, OP_EQ, 65535);
+  tt_int_op(max_out, OP_EQ, 65535);
+
+  ret = parse_port_range("1-65535", &min_out, &max_out);
+  tt_int_op(ret, OP_EQ, 0);
+  tt_int_op(min_out, OP_EQ, 1);
+  tt_int_op(max_out, OP_EQ, 65535);
+
+ done:
+  ;
+}
+
 #define ADDRESS_TEST(name, flags) \
   { #name, test_address_ ## name, flags, NULL, NULL }
 #define ADDRESS_TEST_STR_ARG(name, flags, str_arg) \
@@ -1364,5 +1400,6 @@ struct testcase_t address_tests[] = {
   ADDRESS_TEST(tor_node_in_same_network_family, 0),
   ADDRESS_TEST(dirserv_router_addr_private, 0),
   ADDRESS_TEST_STR_ARG(dirserv_router_addr_private, 0, "allow_private"),
+  ADDRESS_TEST(parse_port_range, 0),
   END_OF_TESTCASES
 };