Hardening around not_resumable sessions

Make sure we can't inadvertently use a not_resumable session

Related to CVE-2024-2511

Reviewed-by: Neil Horman <nhorman@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/24044)

diff --git a/ssl/ssl_sess.c b/ssl/ssl_sess.c
index 241cf43c46296bfe3b710cb634eb4c7408783720..5ce0d308c12b1380d586eef1282f374f026883af 100644 (file)
--- a/ssl/ssl_sess.c
+++ b/ssl/ssl_sess.c
@@ -533,6 +533,12 @@ SSL_SESSION *lookup_sess_in_cache(SSL *s, const unsigned char *sess_id,
         ret = s->session_ctx->get_session_cb(s, sess_id, sess_id_len, &copy);
 
         if (ret != NULL) {
+            if (ret->not_resumable) {
+                /* If its not resumable then ignore this session */
+                if (!copy)
+                    SSL_SESSION_free(ret);
+                return NULL;
+            }
             ssl_tsan_counter(s->session_ctx,
                              &s->session_ctx->stats.sess_cb_hit);