Remove an OPENSSL_assert() and replace with a soft assert and check

Following on from CVE-2017-3733, this removes the OPENSSL_assert() check
that failed and replaces it with a soft assert, and an explicit check of
value with an error return if it fails.

Reviewed-by: Richard Levitte <levitte@openssl.org>

diff --git a/ssl/record/ssl3_record.c b/ssl/record/ssl3_record.c
index 9e99210d899f2eb3cbbfaca5ea477c04d8bdcc5e..df7d012049ebef38d917ec7734a771b037516898 100644 (file)
--- a/ssl/record/ssl3_record.c
+++ b/ssl/record/ssl3_record.c
@@ -7,6 +7,7 @@
  * https://www.openssl.org/source/license.html
  */
 
  * https://www.openssl.org/source/license.html
  */
 

+#include <assert.h>

 #include "../ssl_locl.h"
 #include "internal/constant_time_locl.h"
 #include <openssl/rand.h>
 #include "../ssl_locl.h"
 #include "internal/constant_time_locl.h"
 #include <openssl/rand.h>


@@ -387,13 +388,13 @@ int ssl3_get_record(SSL *s)
         unsigned char *mac;
         /* TODO(size_t): convert this to do size_t properly */
         imac_size = EVP_MD_CTX_size(s->read_hash);
         unsigned char *mac;
         /* TODO(size_t): convert this to do size_t properly */
         imac_size = EVP_MD_CTX_size(s->read_hash);

-        if (imac_size < 0) {
+        assert(imac_size >= 0 && imac_size <= EVP_MAX_MD_SIZE);
+        if (imac_size < 0 || imac_size > EVP_MAX_MD_SIZE) {

                 al = SSL_AD_INTERNAL_ERROR;
                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_LIB_EVP);
                 goto f_err;
         }
         mac_size = (size_t)imac_size;
                 al = SSL_AD_INTERNAL_ERROR;
                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_LIB_EVP);
                 goto f_err;
         }
         mac_size = (size_t)imac_size;

-        OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);

         for (j = 0; j < num_recs; j++) {
             thisrr = &rr[j];
 
         for (j = 0; j < num_recs; j++) {
             thisrr = &rr[j];