commit 4bbaeb4ffafb57ca8e7901995ae274b05be4572b
author mohammad1603 <mohammad.abomokh@arm.com> Thu Feb 22 04:29:04 2018 -0800
committer mohammad1603 <mohammad.abomokh@arm.com> Thu Feb 22 05:04:48 2018 -0800
tree f11268c28f46f306d818d39a97254c00037d97cc
parent d76d8bc9a5383bed1d794846ebaf634327cb2414

Add guard to out_left to avoid negative values

return error when f_send return a value greater than out_left

library/ssl_tls.c

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 617dedb..1de5eaa 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2469,6 +2469,12 @@
         if( ret <= 0 )
             return( ret );
 
+        if( (size_t)ret > ssl->out_left )
+        {
+            MBEDTLS_SSL_DEBUG_MSG( 1, ( "f_send returned value greater than out left size" ) );
+            return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
+        }
+
         ssl->out_left -= ret;
     }