linux-kernel - [PATCH security-next v3 23/29] LSM: Introduce "lsm.order=" for boottime ordering

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: <20180925001832.18322-24-keescook@chromium.org>
Date:   Mon, 24 Sep 2018 17:18:26 -0700
From:   Kees Cook <keescook@...omium.org>
To:     James Morris <jmorris@...ei.org>
Cc:     Kees Cook <keescook@...omium.org>,
        Casey Schaufler <casey@...aufler-ca.com>,
        John Johansen <john.johansen@...onical.com>,
        Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>,
        Paul Moore <paul@...l-moore.com>,
        Stephen Smalley <sds@...ho.nsa.gov>,
        "Schaufler, Casey" <casey.schaufler@...el.com>,
        LSM <linux-security-module@...r.kernel.org>,
        Jonathan Corbet <corbet@....net>, linux-doc@...r.kernel.org,
        linux-arch@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH security-next v3 23/29] LSM: Introduce "lsm.order=" for boottime ordering

Provide a way to reorder LSM initialization using the new "lsm.order="
comma-separated list of LSMs. Any LSMs not listed will be added in builtin
order.

Signed-off-by: Kees Cook <keescook@...omium.org>
---
 Documentation/admin-guide/kernel-parameters.txt |  6 ++++++
 security/security.c                             | 14 +++++++++++++-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 67c90985d2b8..c7c1a0d253ee 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2288,6 +2288,12 @@
 			CONFIG_LSM_ENABLE, and any per-LSM CONFIGs and
 			boot parameters.
 
+	lsm.order=lsm1,...,lsmN
+			[SECURITY] Choose order of enabled LSM
+			initialization. Any builtin LSMs not listed here
+			will be implicitly appended to the list in builtin
+			order.
+
 	machvec=	[IA-64] Force the use of a particular machine-vector
 			(machvec) in a generic kernel.
 			Example: machvec=hpzx1_swiotlb
diff --git a/security/security.c b/security/security.c
index e38df0314f5e..f1c3581d870f 100644
--- a/security/security.c
+++ b/security/security.c
@@ -44,6 +44,7 @@ char *lsm_names;
 /* Boot-time LSM user choice */
 static __initdata const char *chosen_lsm_enable;
 static __initdata const char *chosen_lsm_disable;
+static __initdata const char *chosen_lsm_order;
 static __initdata const char *chosen_major_lsm;
 
 static __initconst const char * const builtin_lsm_enable = CONFIG_LSM_ENABLE;
@@ -160,11 +161,14 @@ static void __init parse_lsm_order(const char *order, const char *origin)
 	kfree(sep);
 }
 
-/* Populate ordered LSMs list from builtin list of LSMs. */
+/* Populate ordered LSMs list from commandline and builtin list of LSMs. */
 static void __init prepare_lsm_order(void)
 {
 	struct lsm_info *lsm;
 
+	/* Parse order from commandline, if present. */
+	parse_lsm_order(chosen_lsm_order, "cmdline");
+
 	/* Parse order from builtin list. */
 	parse_lsm_order(builtin_lsm_order, "builtin");
 
@@ -324,6 +328,14 @@ static int __init choose_major_lsm(char *str)
 }
 __setup("security=", choose_major_lsm);
 
+/* Explicitly choose LSM initialization order. */
+static int __init choose_lsm_order(char *str)
+{
+	chosen_lsm_order = str;
+	return 1;
+}
+__setup("lsm.order=", choose_lsm_order);
+
 /* Enable LSM order debugging. */
 static int __init enable_debug(char *str)
 {
-- 
2.17.1