The following functions now take an extra parameter indicating the size of the output buffer:
mbedtls_ecdsa_write_signature(), mbedtls_ecdsa_write_signature_restartable()mbedtls_pk_sign(), mbedtls_pk_sign_restartable()The requirements for the output buffer have not changed, but passing a buffer that is too small now reliably causes the functions to return an error, rather than overflowing the buffer.