[PATCH] LSM: Ignore "security=" when "lsm=" is specified

From: Kees Cook
Date: Mon Feb 11 2019 - 17:54:09 EST


To avoid potential confusion, explicitly ignore "security=" when "lsm=" is
used on the command line, and report that it is happening.

Suggested-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
security/security.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/security/security.c b/security/security.c
index 3147785e20d7..e6153ed54361 100644
--- a/security/security.c
+++ b/security/security.c
@@ -288,9 +288,13 @@ static void __init ordered_lsm_init(void)
ordered_lsms = kcalloc(LSM_COUNT + 1, sizeof(*ordered_lsms),
GFP_KERNEL);

- if (chosen_lsm_order)
+ if (chosen_lsm_order) {
+ if (chosen_major_lsm) {
+ pr_info("security= is ignored because of lsm=\n");
+ chosen_major_lsm = NULL;
+ }
ordered_lsm_parse(chosen_lsm_order, "cmdline");
- else
+ } else
ordered_lsm_parse(builtin_lsm_order, "builtin");

for (lsm = ordered_lsms; *lsm; lsm++)
--
2.17.1


--
Kees Cook