From 3fc644f246ec88bcb2f1ace61206fd0199f4de3f Mon Sep 17 00:00:00 2001
From: Janos Follath <janos.follath@gmail.com>
Date: Sun, 25 Oct 2015 14:24:10 +0100
Subject: [PATCH] Removed recursion from fix #309.

---
 library/bignum.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/library/bignum.c b/library/bignum.c
index 5e2512343..9c38117b0 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -859,22 +859,21 @@ int mbedtls_mpi_add_abs( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi
     int ret;
     size_t i, j;
     mbedtls_mpi_uint *o, *p, c;
+    mbedtls_mpi TB;
 
     if( X == B )
     {
+        B = A; A = X;
+
         if( B == A )
         {
             // Making a temporary copy instead of shifting by one to deny
             // the possibility of corresponding side-channel attacks.
-            mbedtls_mpi TB;
-
             mbedtls_mpi_init( &TB );
             MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TB, B ) );
             
-            return mbedtls_mpi_add_abs( X, A, &TB );
+            B = &TB;
         }
-
-        B = A; A = X;
     }
 
     if( X != A )
@@ -911,6 +910,10 @@ int mbedtls_mpi_add_abs( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi
     }
 
 cleanup:
+    if( &TB == B ) 
+    {
+        mbedtls_mpi_free( &TB );
+    }
 
     return( ret );
 }