Fix a buffer overflow in hmac_setup_internal
At the end of `psa_hmac_setup_internal()`, the ipad is cleared.
However, the size that was given to clear was `key_len` which is larger
than the size of `ipad`.
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index a80f13d..98239c3 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -2735,7 +2735,7 @@
status = psa_hash_update( &hmac->hash_ctx, ipad, block_size );
cleanup:
- mbedtls_platform_zeroize( ipad, key_length );
+ mbedtls_platform_zeroize( ipad, sizeof(ipad) );
return( status );
}