+++ /dev/null
-From e9d7083e241670332e0443da0f0d4ffb52829f08 Mon Sep 17 00:00:00 2001
-From: Matt Caswell <matt@openssl.org>
-Date: Tue, 5 Mar 2024 15:43:53 +0000
-Subject: [PATCH] Fix unconstrained session cache growth in TLSv1.3
-
-In TLSv1.3 we create a new session object for each ticket that we send.
-We do this by duplicating the original session. If SSL_OP_NO_TICKET is in
-use then the new session will be added to the session cache. However, if
-early data is not in use (and therefore anti-replay protection is being
-used), then multiple threads could be resuming from the same session
-simultaneously. If this happens and a problem occurs on one of the threads,
-then the original session object could be marked as not_resumable. When we
-duplicate the session object this not_resumable status gets copied into the
-new session object. The new session object is then added to the session
-cache even though it is not_resumable.
-
-Subsequently, another bug means that the session_id_length is set to 0 for
-sessions that are marked as not_resumable - even though that session is
-still in the cache. Once this happens the session can never be removed from
-the cache. When that object gets to be the session cache tail object the
-cache never shrinks again and grows indefinitely.
-
-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/24043)
-
-CVE: CVE-2024-2511
-Upstream-Status: Backport [https://github.com/openssl/openssl/commit/e9d7083e241670332e0443da0f0d4ffb52829f08]
-Signed-off-by: Peter Marko <peter.marko@siemens.com>
----
- ssl/ssl_lib.c | 5 +++--
- ssl/ssl_sess.c | 28 ++++++++++++++++++++++------
- ssl/statem/statem_srvr.c | 5 ++---
- 3 files changed, 27 insertions(+), 11 deletions(-)
-
-diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
-index 4afb43bc86e54..c51529ddab5bb 100644
---- a/ssl/ssl_lib.c
-+++ b/ssl/ssl_lib.c
-@@ -4457,9 +4457,10 @@ void ssl_update_cache(SSL_CONNECTION *s, int mode)
-
- /*
- * If the session_id_length is 0, we are not supposed to cache it, and it
-- * would be rather hard to do anyway :-)
-+ * would be rather hard to do anyway :-). Also if the session has already
-+ * been marked as not_resumable we should not cache it for later reuse.
- */
-- if (s->session->session_id_length == 0)
-+ if (s->session->session_id_length == 0 || s->session->not_resumable)
- return;
-
- /*
-diff --git a/ssl/ssl_sess.c b/ssl/ssl_sess.c
-index 3dcc4d81e5bc6..1fa6d17c46863 100644
---- a/ssl/ssl_sess.c
-+++ b/ssl/ssl_sess.c
-@@ -127,16 +127,11 @@ SSL_SESSION *SSL_SESSION_new(void)
- return ss;
- }
-
--SSL_SESSION *SSL_SESSION_dup(const SSL_SESSION *src)
--{
-- return ssl_session_dup(src, 1);
--}
--
- /*
- * Create a new SSL_SESSION and duplicate the contents of |src| into it. If
- * ticket == 0 then no ticket information is duplicated, otherwise it is.
- */
--SSL_SESSION *ssl_session_dup(const SSL_SESSION *src, int ticket)
-+static SSL_SESSION *ssl_session_dup_intern(const SSL_SESSION *src, int ticket)
- {
- SSL_SESSION *dest;
-
-@@ -265,6 +260,27 @@ SSL_SESSION *ssl_session_dup(const SSL_SESSION *src, int ticket)
- return NULL;
- }
-
-+SSL_SESSION *SSL_SESSION_dup(const SSL_SESSION *src)
-+{
-+ return ssl_session_dup_intern(src, 1);
-+}
-+
-+/*
-+ * Used internally when duplicating a session which might be already shared.
-+ * We will have resumed the original session. Subsequently we might have marked
-+ * it as non-resumable (e.g. in another thread) - but this copy should be ok to
-+ * resume from.
-+ */
-+SSL_SESSION *ssl_session_dup(const SSL_SESSION *src, int ticket)
-+{
-+ SSL_SESSION *sess = ssl_session_dup_intern(src, ticket);
-+
-+ if (sess != NULL)
-+ sess->not_resumable = 0;
-+
-+ return sess;
-+}
-+
- const unsigned char *SSL_SESSION_get_id(const SSL_SESSION *s, unsigned int *len)
- {
- if (len)
-diff --git a/ssl/statem/statem_srvr.c b/ssl/statem/statem_srvr.c
-index 853af8c0aa9f9..d5f0ab091dacc 100644
---- a/ssl/statem/statem_srvr.c
-+++ b/ssl/statem/statem_srvr.c
-@@ -2445,9 +2445,8 @@ CON_FUNC_RETURN tls_construct_server_hello(SSL_CONNECTION *s, WPACKET *pkt)
- * so the following won't overwrite an ID that we're supposed
- * to send back.
- */
-- if (s->session->not_resumable ||
-- (!(SSL_CONNECTION_GET_CTX(s)->session_cache_mode & SSL_SESS_CACHE_SERVER)
-- && !s->hit))
-+ if (!(SSL_CONNECTION_GET_CTX(s)->session_cache_mode & SSL_SESS_CACHE_SERVER)
-+ && !s->hit)
- s->session->session_id_length = 0;
-
- if (usetls13) {
projects / thirdparty / openembedded / openembedded-core.git / commitdiff
