[openssl-commits] [openssl] master update

[Matt Caswell]

The branch master has been updated
       via  e6941c7814bb25729d65e1f8e87d1c110a0cbe7e (commit)
      from  ee7002266cbdcfcfe002c94396795c9fb3d5a337 (commit)


- Log -----------------------------------------------------------------
commit e6941c7814bb25729d65e1f8e87d1c110a0cbe7e
Author: Matt Caswell <matt at openssl.org>
Date:   Sat Mar 4 23:58:03 2017 +0000

    Don't call memcmp with a NULL pointer
    
    If early data is sent to a server, but ALPN is not used then memcmp is
    called with a NULL pointer which is undefined behaviour.
    
    Fixes #2841
    
    Reviewed-by: Kurt Roeckx <kurt at openssl.org>
    (Merged from https://github.com/openssl/openssl/pull/2845)

-----------------------------------------------------------------------

Summary of changes:
 ssl/statem/extensions.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/ssl/statem/extensions.c b/ssl/statem/extensions.c
index 8c4013e..fab9bcb 100644
--- a/ssl/statem/extensions.c
+++ b/ssl/statem/extensions.c
@@ -1252,8 +1252,9 @@ static int final_early_data(SSL *s, unsigned int context, int sent, int *al)
             || !s->ext.early_data_ok
             || s->hello_retry_request
             || s->s3->alpn_selected_len != s->session->ext.alpn_selected_len
-            || memcmp(s->s3->alpn_selected, s->session->ext.alpn_selected,
-                      s->s3->alpn_selected_len) != 0){
+            || (s->s3->alpn_selected_len > 0
+                && memcmp(s->s3->alpn_selected, s->session->ext.alpn_selected,
+                          s->s3->alpn_selected_len) != 0)) {
         s->ext.early_data = SSL_EARLY_DATA_REJECTED;
     } else {
         s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;