pkcs11: avoid callig _gnutls_bin2hex() when length is zero.

diff --git a/lib/pkcs11.c b/lib/pkcs11.c
index c32c616a0ef42b9cb84b42be38b218327c8fa622..38630839b65f74833d9ee1a3f18b6909f392ab75 100644 (file)
--- a/lib/pkcs11.c
+++ b/lib/pkcs11.c
@@ -457,7 +457,7 @@ pkcs11_get_info(struct p11_kit_uri *info,
                        *output_size = length * 3;
                        return GNUTLS_E_SHORT_MEMORY_BUFFER;
                }
-               if (output)
+               if (output && length > 0)
                        _gnutls_bin2hex(data, length, output, *output_size,
                                        ":");
                *output_size = length * 3;