diff -up openssl-1.0.2k/crypto/evp/evp_enc.c.int-overflow openssl-1.0.2k/crypto/evp/evp_enc.c

--- openssl-1.0.2k/crypto/evp/evp_enc.c.int-overflow	2021-09-01 14:17:32.813927827 +0200

+++ openssl-1.0.2k/crypto/evp/evp_enc.c	2021-09-01 14:17:32.909929103 +0200

@@ -57,6 +57,7 @@

  */

 #include <stdio.h>

+#include <limits.h>

 #include "cryptlib.h"

 #include <openssl/evp.h>

 #include <openssl/err.h>

@@ -417,6 +418,18 @@ int EVP_EncryptUpdate(EVP_CIPHER_CTX *ct

             return 1;

         } else {

             j = bl - i;

+            /*

+             * Once we've processed the first j bytes from in, the amount of

+             * data left that is a multiple of the block length is:

+             * (inl - j) & ~(bl - 1)

+             * We must ensure that this amount of data, plus the one block that

+             * we process from ctx->buf does not exceed INT_MAX

+             */

+            if (((inl - j) & ~(bl - 1)) > INT_MAX - bl) {

+                EVPerr(EVP_F_EVP_ENCRYPTUPDATE,

+                       EVP_R_OUTPUT_WOULD_OVERFLOW);

+                return 0;

+            } 

             memcpy(&(ctx->buf[i]), in, j);

             if (!M_do_cipher(ctx, out, ctx->buf, bl))

                 return 0;

@@ -518,6 +531,19 @@ int EVP_DecryptUpdate(EVP_CIPHER_CTX *ct

     OPENSSL_assert(b <= sizeof ctx->final);

     if (ctx->final_used) {

+        /*

+         * final_used is only ever set if buf_len is 0. Therefore the maximum

+         * length output we will ever see from evp_EncryptDecryptUpdate is

+         * the maximum multiple of the block length that is <= inl, or just:

+         * inl & ~(b - 1)

+         * Since final_used has been set then the final output length is:

+         * (inl & ~(b - 1)) + b

+         * This must never exceed INT_MAX

+         */

+        if ((inl & ~(b - 1)) > INT_MAX - b) {

+            EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_OUTPUT_WOULD_OVERFLOW);

+            return 0;

+        }

         memcpy(out, ctx->final, b);

         out += b;

         fix_len = 1;

diff -up openssl-1.0.2k/crypto/evp/evp_err.c.int-overflow openssl-1.0.2k/crypto/evp/evp_err.c

--- openssl-1.0.2k/crypto/evp/evp_err.c.int-overflow	2017-01-26 14:22:03.000000000 +0100

+++ openssl-1.0.2k/crypto/evp/evp_err.c	2021-09-01 14:17:32.909929103 +0200

@@ -1,6 +1,6 @@

 /* crypto/evp/evp_err.c */

 /* ====================================================================

- * Copyright (c) 1999-2016 The OpenSSL Project.  All rights reserved.

+ * Copyright (c) 1999-2021 The OpenSSL Project.  All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

@@ -93,6 +93,8 @@ static ERR_STRING_DATA EVP_str_functs[]

      "EVP_CIPHER_CTX_set_key_length"},

     {ERR_FUNC(EVP_F_EVP_DECRYPTFINAL_EX), "EVP_DecryptFinal_ex"},

     {ERR_FUNC(EVP_F_EVP_DIGESTINIT_EX), "EVP_DigestInit_ex"},

+    {ERR_FUNC(EVP_F_EVP_DECRYPTUPDATE), "EVP_DecryptUpdate"},

+    {ERR_FUNC(EVP_F_EVP_ENCRYPTUPDATE), "EVP_EncryptUpdate"},

     {ERR_FUNC(EVP_F_EVP_ENCRYPTFINAL_EX), "EVP_EncryptFinal_ex"},

     {ERR_FUNC(EVP_F_EVP_MD_CTX_COPY_EX), "EVP_MD_CTX_copy_ex"},

     {ERR_FUNC(EVP_F_EVP_MD_SIZE), "EVP_MD_size"},

@@ -213,6 +215,8 @@ static ERR_STRING_DATA EVP_str_reasons[]

     {ERR_REASON(EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE),

      "operation not supported for this keytype"},

     {ERR_REASON(EVP_R_OPERATON_NOT_INITIALIZED), "operaton not initialized"},

+    {ERR_REASON(EVP_R_OUTPUT_WOULD_OVERFLOW),

+    "output would overflow"},

     {ERR_REASON(EVP_R_PKCS8_UNKNOWN_BROKEN_TYPE),

      "pkcs8 unknown broken type"},

     {ERR_REASON(EVP_R_PRIVATE_KEY_DECODE_ERROR), "private key decode error"},

diff -up openssl-1.0.2k/crypto/evp/evp.h.int-overflow openssl-1.0.2k/crypto/evp/evp.h

--- openssl-1.0.2k/crypto/evp/evp.h.int-overflow	2021-09-01 14:17:32.871928598 +0200

+++ openssl-1.0.2k/crypto/evp/evp.h	2021-09-01 14:24:37.803577096 +0200

@@ -1,5 +1,5 @@

 /* crypto/evp/evp.h */

-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

+/* Copyright (C) 1995-2021 Eric Young (eay@cryptsoft.com)

  * All rights reserved.

  *

  * This package is an SSL implementation written

@@ -1404,6 +1404,8 @@ void ERR_load_EVP_strings(void);

 # define EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH              122

 # define EVP_F_EVP_DECRYPTFINAL_EX                        101

 # define EVP_F_EVP_DIGESTINIT_EX                          128

+# define EVP_F_EVP_DECRYPTUPDATE                          180

+# define EVP_F_EVP_ENCRYPTUPDATE                          181

 # define EVP_F_EVP_ENCRYPTFINAL_EX                        127

 # define EVP_F_EVP_MD_CTX_COPY_EX                         110

 # define EVP_F_EVP_MD_SIZE                                162

@@ -1514,6 +1516,7 @@ void ERR_load_EVP_strings(void);

 # define EVP_R_NO_VERIFY_FUNCTION_CONFIGURED              105

 # define EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE   150

 # define EVP_R_OPERATON_NOT_INITIALIZED                   151

+# define EVP_R_OUTPUT_WOULD_OVERFLOW                      184

 # define EVP_R_PKCS8_UNKNOWN_BROKEN_TYPE                  117

 # define EVP_R_PRIVATE_KEY_DECODE_ERROR                   145

 # define EVP_R_PRIVATE_KEY_ENCODE_ERROR                   146