From: Daiki Ueno <ueno@gnu.org>
Date: Sun, 24 Mar 2024 21:45:39 +0000 (+0900)
Subject: gnutls_privkey_decrypt_data: don't free plaintext on failure
X-Git-Tag: 3.8.5~5^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5e8afe0d6bf4e6980ed2fa7e50a773c2fad44ea9;p=thirdparty%2Fgnutls.git

gnutls_privkey_decrypt_data: don't free plaintext on failure

As _wrap_nettle_pk_decrypt uses a locally allocated buffer for the
plaintext, it doesn't need to free the plaintext given by the caller.

Signed-off-by: Daiki Ueno <ueno@gnu.org>
---

diff --git a/lib/nettle/pk.c b/lib/nettle/pk.c
index dd6b9936a8..13546673eb 100644
--- a/lib/nettle/pk.c
+++ b/lib/nettle/pk.c
@@ -1034,7 +1034,6 @@ static int _wrap_nettle_pk_decrypt(gnutls_pk_algorithm_t algo,
 cleanup:
 	gnutls_free(buf);
 	if (ret < 0) {
-		gnutls_free(plaintext->data);
 		_gnutls_switch_fips_state(GNUTLS_FIPS140_OP_ERROR);
 	} else if (not_approved) {
 		_gnutls_switch_fips_state(GNUTLS_FIPS140_OP_NOT_APPROVED);
diff --git a/tests/rsa-rsa-oaep.c b/tests/rsa-rsa-oaep.c
index 175dc6d54f..3a2bd9aa99 100644
--- a/tests/rsa-rsa-oaep.c
+++ b/tests/rsa-rsa-oaep.c
@@ -53,6 +53,7 @@ static void encrypt_decrypt_data(gnutls_privkey_t privkey,
 	gnutls_pubkey_t pubkey;
 	gnutls_datum_t ciphertext = { NULL, 0 };
 	gnutls_datum_t decrypted = { NULL, 0 };
+	gnutls_datum_t uninitialized;
 
 	assert(gnutls_pubkey_init(&pubkey) >= 0);
 	ret = gnutls_pubkey_import_privkey(pubkey, privkey, 0, 0);
@@ -70,6 +71,15 @@ static void encrypt_decrypt_data(gnutls_privkey_t privkey,
 	ret = gnutls_privkey_decrypt_data(privkey, 0, &ciphertext, &decrypted);
 	fips_pop_context(fips_context, exp_state);
 
+	/* gnutls_privkey_decrypt_data shouldn't touch plaintext upon
+	 * failure */
+	assert(ciphertext.size >= 4);
+	memcpy(ciphertext.data, "\xde\xad\xbe\xef", 4);
+	ret = gnutls_privkey_decrypt_data(privkey, 0, &ciphertext,
+					  &uninitialized);
+	if (ret >= 0)
+		fail("gnutls_privkey_decrypt_data unexpectedly succeeded\n");
+
 out:
 	gnutls_pubkey_deinit(pubkey);
 	gnutls_free(ciphertext.data);