Initialise psk_len in mbedtls_ssl_psk_derive_premaster()
@@ -1849,7 +1849,7 @@ int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exch
unsigned char *p = ssl->handshake->premaster;
unsigned char *end = p + sizeof( ssl->handshake->premaster );
const unsigned char *psk;
- size_t psk_len;
+ size_t psk_len = 0;
if( mbedtls_ssl_get_psk( ssl, &psk, &psk_len )
== MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED )
