diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 8e5c02b..2be66ef 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -1884,7 +1884,7 @@
      *
      * opaque psk_identity_hint<0..2^16-1>;
      */
-    if( (*p) > end - 2 )
+    if( end - (*p) < 2 )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message "
                                     "(psk_identity_hint length)" ) );
@@ -1893,7 +1893,7 @@
     len = (*p)[0] << 8 | (*p)[1];
     *p += 2;
 
-    if( (*p) > end -len )
+    if( end - (*p) < len )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad server key exchange message "
                                     "(psk_identity_hint length)" ) );