From 7dd5a23212e3c7bf25a9cd7689681beb89b2d20f Mon Sep 17 00:00:00 2001
From Shao Denghui <shaodenghui@huawei.com>
Date: Tue, 21 Feb 2023 20:12:59 +0800
Subject: [PATCH] [PATCH] 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

Reference: https://github.com/openssl/openssl/commit/6eebe6c0238178356114a96a7858f36b24172847

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>

Signed-off-by: Shao Denghui <shaodenghui@huawei.com>
---
 .../Library/OpensslLib/openssl/crypto/pkcs7/pk7_doit.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/CryptoPkg/Library/OpensslLib/openssl/crypto/pkcs7/pk7_doit.c b/CryptoPkg/Library/OpensslLib/openssl/crypto/pkcs7/pk7_doit.c
index f63fbc5..bbfcf27 100644
--- a/CryptoPkg/Library/OpensslLib/openssl/crypto/pkcs7/pk7_doit.c
+++ b/CryptoPkg/Library/OpensslLib/openssl/crypto/pkcs7/pk7_doit.c
@@ -67,7 +67,10 @@ static int PKCS7_bio_add_digest(BIO **pbio, X509_ALGOR *alg)
         goto err;
     }
 
-    BIO_set_md(btmp, md);
+    if (BIO_set_md(btmp, md) <= 0) {
+        PKCS7err(PKCS7_F_PKCS7_BIO_ADD_DIGEST, ERR_R_BIO_LIB);
+        goto err;
+    }
     if (*pbio == NULL)
         *pbio = btmp;
     else if (!BIO_push(*pbio, btmp)) {
@@ -454,7 +457,10 @@ BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
                 goto err;
             }
 
-            BIO_set_md(btmp, evp_md);
+            if (BIO_set_md(btmp, evp_md) <= 0) {
+                PKCS7err(PKCS7_F_PKCS7_DATADECODE, ERR_R_BIO_LIB);
+                goto err;
+            }
             if (out == NULL)
                 out = btmp;
             else
-- 
2.27.0