From cc9ece9118eeacccc3571c2ee852f8ba067d0607 Mon Sep 17 00:00:00 2001
From: Matt Caswell <matt@openssl.org>
Date: Fri, 15 Mar 2024 17:58:42 +0000
Subject: [PATCH] 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)

(cherry picked from commit c342f4b8bd2d0b375b0e22337057c2eab47d9b96)
---
 ssl/ssl_sess.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ssl/ssl_sess.c b/ssl/ssl_sess.c
index 75adbd9e52..d0b72b7880 100644
--- a/ssl/ssl_sess.c
+++ b/ssl/ssl_sess.c
@@ -531,6 +531,12 @@ 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);
 
-- 
2.33.0