linux-kernel - [PATCH v3 12/14] integrity: Do not allow mok keyring updates following init

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]

Date:   Wed, 11 Aug 2021 22:18:53 -0400
From:   Eric Snowberg <eric.snowberg@...cle.com>
To:     keyrings@...r.kernel.org, linux-integrity@...r.kernel.org,
        zohar@...ux.ibm.com, dhowells@...hat.com, dwmw2@...radead.org,
        herbert@...dor.apana.org.au, davem@...emloft.net,
        jarkko@...nel.org, jmorris@...ei.org, serge@...lyn.com
Cc:     eric.snowberg@...cle.com, keescook@...omium.org,
        gregkh@...uxfoundation.org, torvalds@...ux-foundation.org,
        scott.branden@...adcom.com, weiyongjun1@...wei.com,
        nayna@...ux.ibm.com, ebiggers@...gle.com, ardb@...nel.org,
        nramas@...ux.microsoft.com, lszubowi@...hat.com,
        linux-kernel@...r.kernel.org, linux-crypto@...r.kernel.org,
        linux-security-module@...r.kernel.org,
        James.Bottomley@...senPartnership.com, pjones@...hat.com,
        glin@...e.com, konrad.wilk@...cle.com
Subject: [PATCH v3 12/14] integrity: Do not allow mok keyring updates following init

The mok keyring is setup during init.  No additional keys should be allowed
to be added afterwards.  Leave the permission as read only.

Signed-off-by: Eric Snowberg <eric.snowberg@...cle.com>
---
v2: Initial version
v3: Unmodified from v2
---
 security/integrity/digsig.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index ec94d564c68a..0601ef458e03 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -145,7 +145,8 @@ int __init integrity_init_keyring(const unsigned int id)
 	else
 		restriction->check = restrict_link_to_ima;
 
-	perm |= KEY_USR_WRITE;
+	if (id != INTEGRITY_KEYRING_MOK)
+		perm |= KEY_USR_WRITE;
 
 out:
 	return __integrity_init_keyring(id, perm, restriction);
-- 
2.18.4