diff --git a/library/net_sockets.c b/library/net_sockets.c
index 2876f8f..e19d84a 100644
--- a/library/net_sockets.c
+++ b/library/net_sockets.c
@@ -535,6 +535,13 @@
     if( fd < 0 )
         return( MBEDTLS_ERR_NET_INVALID_CONTEXT );
 
+    /* A limitation of select() is that it only works with file descriptors
+     * up to FD_SETSIZE. This is a limitation of the fd_set type. Error out
+     * early, because attempting to call FD_SET on a large file descriptor
+     * is a buffer overflow on typical platforms. */
+    if( fd >= FD_SETSIZE )
+        return( MBEDTLS_ERR_NET_RECV_FAILED );
+
     FD_ZERO( &read_fds );
     FD_SET( fd, &read_fds );