linux-kernel - [PATCH 3/3] encrypted-keys: fix rcu and sparse messages

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120117204002.14882.4097.stgit@warthog.procyon.org.uk>
Date:	Tue, 17 Jan 2012 20:40:02 +0000
From:	David Howells <dhowells@...hat.com>
To:	jmorris@...ei.org
Cc:	keyrings@...ux-nfs.org, linux-security-module@...r.kernel.org,
	linux-kernel@...r.kernel.org, stable@...nel.org,
	Mimi Zohar <zohar@...ibm.com>,
	David Howells <dhowells@...hat.com>
Subject: [PATCH 3/3] encrypted-keys: fix rcu and sparse messages

From: Mimi Zohar <zohar@...ux.vnet.ibm.com>

Enabling CONFIG_PROVE_RCU and CONFIG_SPARSE_RCU_POINTER resulted in
"suspicious rcu_dereference_check() usage!" and "incompatible types
in comparison expression (different address spaces)" messages.

Access the masterkey directly when holding the rwsem.

Changelog v1:
- Use either rcu_read_lock()/rcu_derefence_key()/rcu_read_unlock()
or remove the unnecessary rcu_derefence() - David Howells

Reported-by: Dmitry Kasatkin <dmitry.kasatkin@...el.com>
Signed-off-by: Mimi Zohar <zohar@...ibm.com>
Signed-off-by: David Howells <dhowells@...hat.com>
---

 security/keys/encrypted-keys/encrypted.c         |    2 +-
 security/keys/encrypted-keys/masterkey_trusted.c |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index d91efb6..2d1bb8a 100644
--- a/security/keys/encrypted-keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -314,7 +314,7 @@ static struct key *request_user_key(const char *master_desc, u8 **master_key,
 		goto error;
 
 	down_read(&ukey->sem);
-	upayload = rcu_dereference(ukey->payload.data);
+	upayload = ukey->payload.data;
 	*master_key = upayload->data;
 	*master_keylen = upayload->datalen;
 error:
diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c
index 8c16c3e..013f7e5 100644
--- a/security/keys/encrypted-keys/masterkey_trusted.c
+++ b/security/keys/encrypted-keys/masterkey_trusted.c
@@ -39,7 +39,7 @@ struct key *request_trusted_key(const char *trusted_desc,
 		goto error;
 
 	down_read(&tkey->sem);
-	tpayload = rcu_dereference(tkey->payload.data);
+	tpayload = tkey->payload.data;
 	*master_key = tpayload->key;
 	*master_keylen = tpayload->key_len;
 error:

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/