diff --git a/library/ssl_ticket.c b/library/ssl_ticket.c
index 23ee122..682beef 100644
--- a/library/ssl_ticket.c
+++ b/library/ssl_ticket.c
@@ -35,6 +35,7 @@
 #define mbedtls_free      free
 #endif
 
+#include "mbedtls/ssl_internal.h"
 #include "mbedtls/ssl_ticket.h"
 
 #include <string.h>
@@ -320,8 +321,7 @@
 
     /* We need at least 4 bytes for key_name, 12 for IV, 2 for len 16 for tag,
      * in addition to session itself, that will be checked when writing it. */
-    if( end - start < TICKET_MIN_LEN )
-        return( MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL );
+    MBEDTLS_SSL_CHK_BUF_PTR( start, end, TICKET_MIN_LEN );
 
 #if defined(MBEDTLS_THREADING_C)
     if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )