LSM: Prepare for reorganizing "security=" logic
This moves the string handling for "security=" boot parameter into
a stored pointer instead of a string duplicate. This will allow
easier handling of the string when switching logic to use the coming
enable/disable infrastructure.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
diff --git a/security/security.c b/security/security.c
index b6d3456..1e1f342 100644
--- a/security/security.c
+++ b/security/security.c
@@ -34,9 +34,6 @@
#define MAX_LSM_EVM_XATTR 2
-/* Maximum number of letters for an LSM name string */
-#define SECURITY_NAME_MAX 10
-
/* How many LSMs were built into the kernel? */
#define LSM_COUNT (__end_lsm_info - __start_lsm_info)
@@ -45,9 +42,8 @@
char *lsm_names;
/* Boot-time LSM user choice */
-static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
- CONFIG_DEFAULT_SECURITY;
static __initdata const char *chosen_lsm_order;
+static __initdata const char *chosen_major_lsm;
static __initconst const char * const builtin_lsm_order = CONFIG_LSM;
@@ -138,7 +134,7 @@
return true;
/* Disabled if this LSM isn't the chosen one. */
- if (strcmp(lsm->name, chosen_lsm) != 0)
+ if (strcmp(lsm->name, chosen_major_lsm) != 0)
return false;
return true;
@@ -168,6 +164,9 @@
struct lsm_info *lsm;
char *sep, *name, *next;
+ if (!chosen_major_lsm)
+ chosen_major_lsm = CONFIG_DEFAULT_SECURITY;
+
sep = kstrdup(order, GFP_KERNEL);
next = sep;
/* Walk the list, looking for matching LSMs. */
@@ -257,12 +256,12 @@
}
/* Save user chosen LSM */
-static int __init choose_lsm(char *str)
+static int __init choose_major_lsm(char *str)
{
- strncpy(chosen_lsm, str, SECURITY_NAME_MAX);
+ chosen_major_lsm = str;
return 1;
}
-__setup("security=", choose_lsm);
+__setup("security=", choose_major_lsm);
/* Explicitly choose LSM initialization order. */
static int __init choose_lsm_order(char *str)