From d3b6dfd70db844c4499bec6ad6601623a565e674 Mon Sep 17 00:00:00 2001
From: Tomas Mraz <tomas@openssl.org>
Date: Wed, 18 Jan 2023 09:27:53 +0100
Subject: [PATCH 15/18] pk7_doit.c: Check return of BIO_set_md() calls

These calls invoke EVP_DigestInit() which can fail for digests
with implicit fetches. Subsequent EVP_DigestUpdate() from BIO_write()
or EVP_DigestFinal() from BIO_read() will segfault on NULL
dereference. This can be triggered by an attacker providing
PKCS7 data digested with MD4 for example if the legacy provider
is not loaded.

If BIO_set_md() fails the md BIO cannot be used.

CVE-2023-0401

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
---
 crypto/pkcs7/pk7_doit.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/crypto/pkcs7/pk7_doit.c b/crypto/pkcs7/pk7_doit.c
index bde9ac4787..5e562fbea5 100644
--- a/crypto/pkcs7/pk7_doit.c
+++ b/crypto/pkcs7/pk7_doit.c
@@ -84,7 +84,11 @@ static int pkcs7_bio_add_digest(BIO **pbio, X509_ALGOR *alg,
     }
     (void)ERR_pop_to_mark();
 
-    BIO_set_md(btmp, md);
+    if (BIO_set_md(btmp, md) <= 0) {
+        ERR_raise(ERR_LIB_PKCS7, ERR_R_BIO_LIB);
+        EVP_MD_free(fetched);
+        goto err;
+    }
     EVP_MD_free(fetched);
     if (*pbio == NULL)
         *pbio = btmp;
@@ -522,7 +526,11 @@ BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
             }
             (void)ERR_pop_to_mark();
 
-            BIO_set_md(btmp, md);
+            if (BIO_set_md(btmp, md) <= 0) {
+                EVP_MD_free(evp_md);
+                ERR_raise(ERR_LIB_PKCS7, ERR_R_BIO_LIB);
+                goto err;
+            }
             EVP_MD_free(evp_md);
             if (out == NULL)
                 out = btmp;
-- 
2.39.1

From a0f2359613f50b5ca6b74b78bf4b54d7dc925fd2 Mon Sep 17 00:00:00 2001
From: Tomas Mraz <tomas@openssl.org>
Date: Wed, 18 Jan 2023 17:07:24 +0100
Subject: [PATCH 16/18] Add testcase for missing return check of BIO_set_md()
 calls

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
---
 test/recipes/80-test_cms.t                  | 15 ++++++++--
 test/recipes/80-test_cms_data/pkcs7-md4.pem | 32 +++++++++++++++++++++
 2 files changed, 45 insertions(+), 2 deletions(-)
 create mode 100644 test/recipes/80-test_cms_data/pkcs7-md4.pem

diff --git a/test/recipes/80-test_cms.t b/test/recipes/80-test_cms.t
index fd53683e6b..d45789de70 100644
--- a/test/recipes/80-test_cms.t
+++ b/test/recipes/80-test_cms.t
@@ -13,7 +13,7 @@ use warnings;
 use POSIX;
 use File::Spec::Functions qw/catfile/;
 use File::Compare qw/compare_text compare/;
-use OpenSSL::Test qw/:DEFAULT srctop_dir srctop_file bldtop_dir bldtop_file with/;
+use OpenSSL::Test qw/:DEFAULT srctop_dir srctop_file bldtop_dir bldtop_file with data_file/;
 
 use OpenSSL::Test::Utils;
 
@@ -50,7 +50,7 @@ my ($no_des, $no_dh, $no_dsa, $no_ec, $no_ec2m, $no_rc2, $no_zlib)
 
 $no_rc2 = 1 if disabled("legacy");
 
-plan tests => 13;
+plan tests => 14;
 
 ok(run(test(["pkcs7_test"])), "test pkcs7");
 
@@ -941,6 +941,17 @@ subtest "CMS binary input tests\n" => sub {
        "verify binary input with -binary missing -crlfeol");
 };
 
+# Test case for missing MD algorithm (must not segfault)
+
+with({ exit_checker => sub { return shift == 4; } },
+    sub {
+        ok(run(app(['openssl', 'smime', '-verify', '-noverify',
+                    '-inform', 'PEM',
+                    '-in', data_file("pkcs7-md4.pem"),
+                   ])),
+            "Check failure of EVP_DigestInit is handled correctly");
+    });
+
 sub check_availability {
     my $tnam = shift;
 
diff --git a/test/recipes/80-test_cms_data/pkcs7-md4.pem b/test/recipes/80-test_cms_data/pkcs7-md4.pem
new file mode 100644
index 0000000000..ecff611deb
--- /dev/null
+++ b/test/recipes/80-test_cms_data/pkcs7-md4.pem
@@ -0,0 +1,32 @@
+-----BEGIN PKCS7-----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+-----END PKCS7-----
-- 
2.39.1