diff --git a/netwerk/base/nsIOService.cpp b/netwerk/base/nsIOService.cpp
index 55f40a41ef..d04b3cef12 100644
--- a/netwerk/base/nsIOService.cpp
+++ b/netwerk/base/nsIOService.cpp
@@ -1210,7 +1210,7 @@ nsIOService::AllowPort(int32_t inPort, const char *scheme, bool *_retval)
     }
 
     // Ensure the port number is within a valid range
-    if (port <= 0 || port >= std::numeric_limits<uint16_t>::max()) {
+    if (port <= 0 || port > std::numeric_limits<uint16_t>::max()) {
         *_retval = false;
         return NS_OK;
     }