From 1a55309207cb2edd012062379c82da45ba6bbe9d Mon Sep 17 00:00:00 2001
From: Jacob Barthelmeh <jacob@wolfssl.com>
Date: Thu, 5 Jan 2017 10:00:17 -0700
Subject: [PATCH 1/3] fix possible memory leak on error case with ASN1 INTEGER
 to BN function

---
 src/ssl.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/ssl.c b/src/ssl.c
index ff297b4f7..4d12a13bd 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -16570,8 +16570,17 @@ WOLFSSL_BIGNUM *wolfSSL_ASN1_INTEGER_to_BN(const WOLFSSL_ASN1_INTEGER *ai,
         return NULL;
     }
 
-    if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
-        return NULL;
+    /* SetIndividualExternal mallocs bn in the case that bn is NULL */
+    if (bn == NULL) {
+        if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
+            wolfSSL_BN_free(bn);
+            return NULL;
+        }
+    }
+    else {
+        if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
+            return NULL;
+        }
     }
 
     return bn;

From 1afb7e20db8876b22b7c774d0e2e01f61f5d29a2 Mon Sep 17 00:00:00 2001
From: Jacob Barthelmeh <jacob@wolfssl.com>
Date: Thu, 5 Jan 2017 13:49:07 -0700
Subject: [PATCH 2/3] fix for freeing copy of mpi in the case of not using
 fastmath

---
 src/ssl.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/ssl.c b/src/ssl.c
index 4d12a13bd..8dc27190d 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -16502,6 +16502,10 @@ void wolfSSL_RSA_free(WOLFSSL_RSA* rsa)
  * declared and then not used. */
 #if !defined(NO_ASN) || !defined(NO_DSA) || defined(HAVE_ECC) || \
     (!defined(NO_RSA) && !defined(HAVE_USER_RSA) && !defined(HAVE_FAST_RSA))
+/* when calling SetIndividualExternal, mpi should be cleared by caller if no
+ * longer used. ie mp_clear(mpi). This is to free data when fastmath is
+ * disabled since a copy of mpi is made by this function and placed into bn.
+ */
 static int SetIndividualExternal(WOLFSSL_BIGNUM** bn, mp_int* mpi)
 {
     WOLFSSL_MSG("Entering SetIndividualExternal");
@@ -16570,18 +16574,23 @@ WOLFSSL_BIGNUM *wolfSSL_ASN1_INTEGER_to_BN(const WOLFSSL_ASN1_INTEGER *ai,
         return NULL;
     }
 
-    /* SetIndividualExternal mallocs bn in the case that bn is NULL */
+    /* SetIndividualExternal mallocs bn in the case that bn is NULL
+     * mp_clear needs called because mpi is copied and causes memory leak with
+     * --disable-fastmath */
     if (bn == NULL) {
         if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
             wolfSSL_BN_free(bn);
+            mp_clear(&mpi);
             return NULL;
         }
     }
     else {
         if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
+            mp_clear(&mpi);
             return NULL;
         }
     }
+    mp_clear(&mpi);
 
     return bn;
 }

From 36d34ce0692da86375be28076132a076590ebf6a Mon Sep 17 00:00:00 2001
From: Jacob Barthelmeh <jacob@wolfssl.com>
Date: Wed, 11 Jan 2017 14:53:32 -0700
Subject: [PATCH 3/3] free WOLFSSL_BN in SetIndividualExternal error case and
 simplify mpi_clear call

---
 src/ssl.c | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/src/ssl.c b/src/ssl.c
index 8dc27190d..23fb7e4fb 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -16508,6 +16508,8 @@ void wolfSSL_RSA_free(WOLFSSL_RSA* rsa)
  */
 static int SetIndividualExternal(WOLFSSL_BIGNUM** bn, mp_int* mpi)
 {
+    byte dynamic = 0;
+
     WOLFSSL_MSG("Entering SetIndividualExternal");
 
     if (mpi == NULL || bn == NULL) {
@@ -16521,10 +16523,14 @@ static int SetIndividualExternal(WOLFSSL_BIGNUM** bn, mp_int* mpi)
             WOLFSSL_MSG("SetIndividualExternal alloc failed");
             return SSL_FATAL_ERROR;
         }
+        dynamic = 1;
     }
 
     if (mp_copy(mpi, (mp_int*)((*bn)->internal)) != MP_OKAY) {
         WOLFSSL_MSG("mp_copy error");
+        if (dynamic == 1) {
+            wolfSSL_BN_free(*bn);
+        }
         return SSL_FATAL_ERROR;
     }
 
@@ -16574,24 +16580,14 @@ WOLFSSL_BIGNUM *wolfSSL_ASN1_INTEGER_to_BN(const WOLFSSL_ASN1_INTEGER *ai,
         return NULL;
     }
 
-    /* SetIndividualExternal mallocs bn in the case that bn is NULL
-     * mp_clear needs called because mpi is copied and causes memory leak with
+    /* mp_clear needs called because mpi is copied and causes memory leak with
      * --disable-fastmath */
-    if (bn == NULL) {
-        if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
-            wolfSSL_BN_free(bn);
-            mp_clear(&mpi);
-            return NULL;
-        }
-    }
-    else {
-        if (SetIndividualExternal(&bn, &mpi) != SSL_SUCCESS) {
-            mp_clear(&mpi);
-            return NULL;
-        }
-    }
+    ret = SetIndividualExternal(&bn, &mpi);
     mp_clear(&mpi);
 
+    if (ret != SSL_SUCCESS) {
+        return NULL;
+    }
     return bn;
 }
 #endif /* !NO_ASN */