File ovmf-bsc1177789-cryptopkg-fix-null-dereference.patch of Package ovmf.28617
From e0a63f1772d314f64b9307d2a5019b85a5ef84a8 Mon Sep 17 00:00:00 2001
From: Jian J Wang <jian.j.wang@intel.com>
Date: Thu, 25 Apr 2019 23:42:16 +0800
Subject: [PATCH 1/1] CryptoPkg/BaseCryptLib: fix NULL dereference
(CVE-2019-14584)
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1914
AuthenticodeVerify() calls OpenSSLs d2i_PKCS7() API to parse asn encoded
signed authenticode pkcs#7 data. when this successfully returns, a type
check is done by calling PKCS7_type_is_signed() and then
Pkcs7->d.sign->contents->type is used. It is possible to construct an asn1
blob that successfully decodes and have d2i_PKCS7() return a valid pointer
and have PKCS7_type_is_signed() also return success but have Pkcs7->d.sign
be a NULL pointer.
Looking at how PKCS7_verify() [inside of OpenSSL] implements checking for
pkcs7 structs it does the following:
- call PKCS7_type_is_signed()
- call PKCS7_get_detached()
Looking into how PKCS7_get_detatched() is implemented, it checks to see if
p7->d.sign is NULL or if p7->d.sign->contents->d.ptr is NULL.
As such, the fix is to do the same as OpenSSL after calling d2i_PKCS7().
- Add call to PKS7_get_detached() to existing error handling
Cc: Xiaoyu Lu <xiaoyux.lu@intel.com>
Cc: Guomin Jiang <guomin.jiang@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>
(cherry picked from commit 26442d11e620a9e81c019a24a4ff38441c64ba10)
---
CryptoPkg/Library/BaseCryptLib/Pk/CryptAuthenticode.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/CryptoPkg/Library/BaseCryptLib/Pk/CryptAuthenticode.c b/CryptoPkg/Library/BaseCryptLib/Pk/CryptAuthenticode.c
index 2772b1e2be3c..3c2d14a88bce 100644
--- a/CryptoPkg/Library/BaseCryptLib/Pk/CryptAuthenticode.c
+++ b/CryptoPkg/Library/BaseCryptLib/Pk/CryptAuthenticode.c
@@ -9,7 +9,7 @@
AuthenticodeVerify() will get PE/COFF Authenticode and will do basic check for
data structure.
-Copyright (c) 2011 - 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2011 - 2020, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
@@ -100,7 +100,7 @@ AuthenticodeVerify (
//
// Check if it's PKCS#7 Signed Data (for Authenticode Scenario)
//
- if (!PKCS7_type_is_signed (Pkcs7)) {
+ if (!PKCS7_type_is_signed (Pkcs7) || PKCS7_get_detached (Pkcs7)) {
goto _Exit;
}
--
2.28.0