9f776e8d93
- Security fix: [bsc#1222548, CVE-2024-2511] * Fix unconstrained session cache growth in TLSv1.3 * Add openssl-CVE-2024-2511.patch OBS-URL: https://build.opensuse.org/request/show/1172426 OBS-URL: https://build.opensuse.org/package/show/security:tls/openssl-1_1?expand=0&rev=160
119 lines
4.3 KiB
Diff
119 lines
4.3 KiB
Diff
From b52867a9f618bb955bed2a3ce3db4d4f97ed8e5d 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/24044)
|
|
|
|
(cherry picked from commit 7e4d731b1c07201ad9374c1cd9ac5263bdf35bce)
|
|
---
|
|
ssl/ssl_lib.c | 5 +++--
|
|
ssl/ssl_sess.c | 28 ++++++++++++++++++++++------
|
|
ssl/statem/statem_srvr.c | 5 ++---
|
|
3 files changed, 27 insertions(+), 11 deletions(-)
|
|
|
|
Index: openssl-1.1.1w/ssl/ssl_lib.c
|
|
===================================================================
|
|
--- openssl-1.1.1w.orig/ssl/ssl_lib.c
|
|
+++ openssl-1.1.1w/ssl/ssl_lib.c
|
|
@@ -3524,9 +3524,10 @@ void ssl_update_cache(SSL *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;
|
|
|
|
/*
|
|
Index: openssl-1.1.1w/ssl/ssl_sess.c
|
|
===================================================================
|
|
--- openssl-1.1.1w.orig/ssl/ssl_sess.c
|
|
+++ openssl-1.1.1w/ssl/ssl_sess.c
|
|
@@ -94,16 +94,11 @@ SSL_SESSION *SSL_SESSION_new(void)
|
|
return ss;
|
|
}
|
|
|
|
-SSL_SESSION *SSL_SESSION_dup(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(SSL_SESSION *src, int ticket)
|
|
+static SSL_SESSION *ssl_session_dup_intern(SSL_SESSION *src, int ticket)
|
|
{
|
|
SSL_SESSION *dest;
|
|
|
|
@@ -226,6 +221,27 @@ SSL_SESSION *ssl_session_dup(SSL_SESSION
|
|
return NULL;
|
|
}
|
|
|
|
+SSL_SESSION *SSL_SESSION_dup(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(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)
|
|
Index: openssl-1.1.1w/ssl/statem/statem_srvr.c
|
|
===================================================================
|
|
--- openssl-1.1.1w.orig/ssl/statem/statem_srvr.c
|
|
+++ openssl-1.1.1w/ssl/statem/statem_srvr.c
|
|
@@ -2403,9 +2403,8 @@ int tls_construct_server_hello(SSL *s, W
|
|
* so the following won't overwrite an ID that we're supposed
|
|
* to send back.
|
|
*/
|
|
- if (s->session->not_resumable ||
|
|
- (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
|
|
- && !s->hit))
|
|
+ if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
|
|
+ && !s->hit)
|
|
s->session->session_id_length = 0;
|
|
|
|
if (usetls13) {
|