Re: [PATCH 23/28] security: Introduce LSM_ORDER_LAST
From: Mimi Zohar <zohar@linux.ibm.com>
Date: 2023-03-08 13:18:02
Also in:
keyrings, linux-fsdevel, linux-integrity, linux-nfs, lkml, selinux
Hi Roberto, On Fri, 2023-03-03 at 19:25 +0100, Roberto Sassu wrote:
From: Roberto Sassu <roberto.sassu@huawei.com> Introduce LSM_ORDER_LAST, to satisfy the requirement of LSMs willing to be the last, e.g. the 'integrity' LSM, without changing the kernel command line or configuration.
Please reframe this as a bug fix for 79f7865d844c ("LSM: Introduce
"lsm=" for boottime LSM selection") and upstream it first, with
'integrity' as the last LSM. The original bug fix commit 92063f3ca73a
("integrity: double check iint_cache was initialized") could then be
removed.
As for LSM_ORDER_FIRST, LSMs with LSM_ORDER_LAST are always enabled and put at the end of the LSM list in no particular order.
^Similar to LSM_ORDER_FIRST ... And remove "in no particular order".
quoted hunk ↗ jump to hunk
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> --- include/linux/lsm_hooks.h | 1 + security/security.c | 12 +++++++++--- 2 files changed, 10 insertions(+), 3 deletions(-)diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 21a8ce23108..05c4b831d99 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h@@ -93,6 +93,7 @@ extern void security_add_hooks(struct security_hook_list *hooks, int count, enum lsm_order { LSM_ORDER_FIRST = -1, /* This is only for capabilities. */ LSM_ORDER_MUTABLE = 0, + LSM_ORDER_LAST = 1, }; struct lsm_info {diff --git a/security/security.c b/security/security.c index 322090a50cd..24f52ba3218 100644 --- a/security/security.c +++ b/security/security.c@@ -284,9 +284,9 @@ static void __init ordered_lsm_parse(const char *order, const char *origin) bool found = false; for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { - if (lsm->order == LSM_ORDER_MUTABLE && - strcmp(lsm->name, name) == 0) { - append_ordered_lsm(lsm, origin); + if (strcmp(lsm->name, name) == 0) { + if (lsm->order == LSM_ORDER_MUTABLE) + append_ordered_lsm(lsm, origin); found = true; } }@@ -306,6 +306,12 @@ static void __init ordered_lsm_parse(const char *order, const char *origin) } } + /* LSM_ORDER_LAST is always last. */ + for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { + if (lsm->order == LSM_ORDER_LAST) + append_ordered_lsm(lsm, " last"); + } + /* Disable all LSMs not in the ordered list. */ for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { if (exists_ordered_lsm(lsm))
-- thanks, Mimi