diff --git a/library/ecdsa.c b/library/ecdsa.c
index 3a11e18..a9734f6 100644
--- a/library/ecdsa.c
+++ b/library/ecdsa.c
@@ -722,7 +722,7 @@
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &p, buf,
                                        MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) );
 
-    memcpy( sig, p, len );
+    mbedtls_platform_memcpy( sig, p, len );
     *slen = len;
 
     return( 0 );