IMA_APPRAISE_BOOTPARAM has been marked as dependent on !IMA_ARCH_POLICY in compile time, enforcing the appraisal whenever the kernel had the arch policy option enabled.
However it breaks systems where the option is actually set but the system wasn't booted in a "secure boot" platform. In this scenario, anytime the an appraisal policy (i.e. ima_policy=appraisal_tcb) is used it will be forced, giving no chance to the user set the 'fix' state (ima_appraise=fix) to actually measure system's files.
This patch remove this compile time dependency and move it to a runtime decision, based on the arch policy loading failure/success.
Cc: stable@vger.kernel.org Fixes: d958083a8f64 ("x86/ima: define arch_get_ima_policy() for x86") Signed-off-by: Bruno Meneguele bmeneg@redhat.com --- changes from v1: - removed "ima:" prefix from pr_info() message
security/integrity/ima/Kconfig | 2 +- security/integrity/ima/ima_policy.c | 8 ++++++-- 2 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index edde88dbe576..62dc11a5af01 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -232,7 +232,7 @@ config IMA_APPRAISE_REQUIRE_POLICY_SIGS
config IMA_APPRAISE_BOOTPARAM bool "ima_appraise boot parameter" - depends on IMA_APPRAISE && !IMA_ARCH_POLICY + depends on IMA_APPRAISE default y help This option enables the different "ima_appraise=" modes diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index e493063a3c34..c876617d4210 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -733,11 +733,15 @@ void __init ima_init_policy(void) * (Highest priority) */ arch_entries = ima_init_arch_policy(); - if (!arch_entries) + if (!arch_entries) { pr_info("No architecture policies found\n"); - else + } else { + /* Force appraisal, preventing runtime xattr changes */ + pr_info("setting IMA appraisal to enforced\n"); + ima_appraise = IMA_APPRAISE_ENFORCE; add_rules(arch_policy_entry, arch_entries, IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY); + }
/* * Insert the builtin "secure_boot" policy rules requiring file