diff --git a/ChangeLog b/ChangeLog
index aee1f38f5f..f61d867143 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Fri Oct 23 00:32:02 2015  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* ext/openssl/ossl_ssl.c (ssl_npn_select_cb): explicitly raise error
+	  in ext/openssl instead of OpenSSL itself because LibreSSL
+	  silently truncate the selected protocol name by casting the length
+	  from int to unsigned char. [Bug #11369]
+	  Patch by Jeremy Evans <merch-redmine@jeremyevans.net>
+
 Fri Oct 23 00:49:45 2015  Shugo Maeda  <shugo@ruby-lang.org>
 
 	* lib/un.rb (help): change the name of a block parameter to avoid
diff --git a/ext/openssl/ossl_ssl.c b/ext/openssl/ossl_ssl.c
index 3e6e164682..ae9f3ca8d7 100644
--- a/ext/openssl/ossl_ssl.c
+++ b/ext/openssl/ossl_ssl.c
@@ -599,9 +599,12 @@ ssl_npn_select_cb(SSL *s, unsigned char **out, unsigned char *outlen, const unsi
 
     selected = rb_funcall(cb, rb_intern("call"), 1, protocols);
     StringValue(selected);
+    i = RSTRING_LENINT(selected);
+    if (i < 1 || i >= 256) {
+	    ossl_raise(eSSLError, "Selected protocol must have length 1..255");
+    }
     *out = (unsigned char *) StringValuePtr(selected);
-    *outlen = RSTRING_LENINT(selected);
-
+    *outlen = i;
     return SSL_TLSEXT_ERR_OK;
 }