openssl: Security fix CVE-2016-6304

affects openssl < 1.0.2i

Reference:
https://www.openssl.org/news/secadv/20160922.txt

Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
Signed-off-by: Adrian Dudau <adrian.dudau@enea.com>

2 files changed, 76 insertions, 0 deletions

diff --git a/recipes-connectivity/openssl/openssl/CVE-2016-6304.patch b/recipes-connectivity/openssl/openssl/CVE-2016-6304.patch
new file mode 100644
index 0000000..64508b5
--- /dev/null
+++ b/recipes-connectivity/openssl/openssl/CVE-2016-6304.patch
@@ -0,0 +1,75 @@
+From ea39b16b71e4e72a228a4535bd6d6a02c5edbc1f Mon Sep 17 00:00:00 2001
+From: Matt Caswell <matt@openssl.org>
+Date: Fri, 9 Sep 2016 10:08:45 +0100
+Subject: [PATCH] Fix OCSP Status Request extension unbounded memory growth
+
+A malicious client can send an excessively large OCSP Status Request
+extension. If that client continually requests renegotiation,
+sending a large OCSP Status Request extension each time, then there will
+be unbounded memory growth on the server. This will eventually lead to a
+Denial Of Service attack through memory exhaustion. Servers with a
+default configuration are vulnerable even if they do not support OCSP.
+Builds using the "no-ocsp" build time option are not affected.
+
+I have also checked other extensions to see if they suffer from a similar
+problem but I could not find any other issues.
+
+CVE-2016-6304
+
+Issue reported by Shi Lei.
+
+Reviewed-by: Rich Salz <rsalz@openssl.org>
+
+Upstream-Status: Backport
+CVE: CVE-2016-6304
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ ssl/t1_lib.c | 24 +++++++++++++++++-------
+ 1 file changed, 17 insertions(+), 7 deletions(-)
+
+diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
+index fbcf2e6..e4b4e27 100644
+--- a/ssl/t1_lib.c
++++ b/ssl/t1_lib.c
+@@ -2316,6 +2316,23 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p,
+                 size -= 2;
+                 if (dsize > size)
+                     goto err;
++
++                /*
++                 * We remove any OCSP_RESPIDs from a previous handshake
++                 * to prevent unbounded memory growth - CVE-2016-6304
++                 */
++                sk_OCSP_RESPID_pop_free(s->tlsext_ocsp_ids,
++                                        OCSP_RESPID_free);
++                if (dsize > 0) {
++                    s->tlsext_ocsp_ids = sk_OCSP_RESPID_new_null();
++                    if (s->tlsext_ocsp_ids == NULL) {
++                        *al = SSL_AD_INTERNAL_ERROR;
++                        return 0;
++                    }
++                } else {
++                    s->tlsext_ocsp_ids = NULL;
++                }
++
+                 while (dsize > 0) {
+                     OCSP_RESPID *id;
+                     int idsize;
+@@ -2335,13 +2352,6 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p,
+                         OCSP_RESPID_free(id);
+                         goto err;
+                     }
+-                    if (!s->tlsext_ocsp_ids
+-                        && !(s->tlsext_ocsp_ids =
+-                             sk_OCSP_RESPID_new_null())) {
+-                        OCSP_RESPID_free(id);
+-                        *al = SSL_AD_INTERNAL_ERROR;
+-                        return 0;
+-                    }
+                     if (!sk_OCSP_RESPID_push(s->tlsext_ocsp_ids, id)) {
+                         OCSP_RESPID_free(id);
+                         *al = SSL_AD_INTERNAL_ERROR;
+-- 
+2.7.4
+
diff --git a/recipes-connectivity/openssl/openssl_1.0.2h.bbappend b/recipes-connectivity/openssl/openssl_1.0.2h.bbappend
index 528a77c..e4a9912 100644
--- a/recipes-connectivity/openssl/openssl_1.0.2h.bbappend
+++ b/recipes-connectivity/openssl/openssl_1.0.2h.bbappend
@@ -9,4 +9,5 @@ SRC_URI += "file://CVE-2016-2178.patch \
            file://CVE-2016-2182.patch \
            file://CVE-2016-6302.patch \
            file://CVE-2016-6303.patch \
+           file://CVE-2016-6304.patch \
            "