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@xxxxxxxxxxxx>
---
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
