OPENSSL_clear_free instead of OPENSSL_free

[ManSoSec]

It seems OPENSSL_clear_free needs to be called instead of OPENSSL_free here:

openssl/crypto/sm2/sm2_sign.c

Line 475 in 1903a9b

OPENSSL_free(der);

As it has done here:

openssl/crypto/ec/ecdsa_ossl.c

Line 347 in 1903a9b

OPENSSL_clear_free(der, derlen);

[romen]

In the verify path nothing is secret, so actually we should use free instead of clear_free also in the ecdsa part!

[mattcaswell]

Yes - agreed. OPENSSL_free is sufficient. Still a bug - but in ecdsa_ossl.c not sm2_sign.c