Fix by copying one byte less than the buffer size. We anyway overwrite the
last byte.
Signed-off-by: Juergen Christ <jchrist@linux.ibm.com> Reviewed-by: Paul Dale <pauli@openssl.org> Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15993)