[PATCH v3] KEYS: use kfree_sensitive with key

From: Mahmoud Adam <mngyadam@amazon.com>
To: <dhowells@redhat.com>
Cc: <herbert@gondor.apana.org.au>, <davem@davemloft.net>,
	<keyrings@vger.kernel.org>, <linux-crypto@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	Mahmoud Adam <mngyadam@amazon.com>
Subject: [PATCH v3] KEYS: use kfree_sensitive with key
Date: Thu, 22 Jun 2023 12:47:22 +0000	[thread overview]
Message-ID: <20230622124719.93393-1-mngyadam@amazon.com> (raw)

key might contain private part of the key, so better use
kfree_sensitive to free it
---
v1: conflicts with c3d03e8e35e0:
KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()
kfree_sensitive the buf variable also because it might has private
part

 crypto/asymmetric_keys/public_key.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index 50c933f86b21..170f06982381 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -43,7 +43,7 @@ static void public_key_describe(const struct key *asymmetric_key,
 void public_key_free(struct public_key *key)
 {
 	if (key) {
-		kfree(key->key);
+		kfree_sensitive(key->key);
 		kfree(key->params);
 		kfree(key);
 	}
@@ -218,7 +218,7 @@ static int software_key_query(const struct kernel_pkey_params *params,
 	ret = 0;

 error_free_key:
-	kfree(key);
+	kfree_sensitive(key);
 error_free_tfm:
 	crypto_free_akcipher(tfm);
 	pr_devel("<==%s() = %d\n", __func__, ret);
@@ -303,7 +303,7 @@ static int software_key_eds_op(struct kernel_pkey_params *params,
 		ret = req->dst_len;

 error_free_key:
-	kfree(key);
+	kfree_sensitive(key);
 error_free_req:
 	akcipher_request_free(req);
 error_free_tfm:
@@ -460,7 +460,7 @@ int public_key_verify_signature(const struct public_key *pkey,
 	ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);

 error_free_buf:
-	kfree(buf);
+	kfree_sensitive(buf);
 error_free_req:
 	akcipher_request_free(req);
 error_free_tfm:
--
2.40.1
