commit 8a3170571e886718699776777ab7fbb44320d4f1
author Janos Follath <janos.follath@arm.com> Thu Apr 21 23:37:09 2016 +0100
committer Simon Butcher <simon.butcher@arm.com> Fri Apr 22 00:41:54 2016 +0100
tree b6878b345a80d60ea1f30b0a94dcd4460d49d086
parent 55abc215219ace39bc9c882a50ecd933bfc46663

Fix bug in ssl_write_supported_elliptic_curves_ext

Passing invalid curves to mbedtls_ssl_conf_curves potentially could caused a
crash later in ssl_write_supported_elliptic_curves_ext. #373

library/ssl_cli.c

diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 52ddf9a..7f5b94e 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -270,6 +270,12 @@
     for( info = mbedtls_ecp_curve_list(); info->grp_id != MBEDTLS_ECP_DP_NONE; info++ )
     {
 #endif
+        if( info == NULL )
+        {
+            MBEDTLS_SSL_DEBUG_MSG( 1, ( "invalid curve in ssl configuration" ) );
+            return;
+        }
+
         elliptic_curve_len += 2;
     }
 
@@ -289,7 +295,6 @@
     for( info = mbedtls_ecp_curve_list(); info->grp_id != MBEDTLS_ECP_DP_NONE; info++ )
     {
 #endif
-
         elliptic_curve_list[elliptic_curve_len++] = info->tls_id >> 8;
         elliptic_curve_list[elliptic_curve_len++] = info->tls_id & 0xFF;
     }