ima: Set again build_ima_appraise variable

BugLink: https://bugs.launchpad.net/bugs/1885023
[ Upstream commit b59fda449cf07f2db3be3a67142e6c000f5e8d79 ]

After adding the new add_rule() function in commit c52657d93b05
("ima: refactor ima_init_policy()"), all appraisal flags are added to the
temp_ima_appraise variable. Revert to the previous behavior instead of
removing build_ima_appraise, to benefit from the protection offered by
__ro_after_init.

The mentioned commit introduced a bug, as it makes all the flags
modifiable, while build_ima_appraise flags can be protected with
__ro_after_init.

Cc: stable@vger.kernel.org # 5.0.x
Fixes: c52657d93b05 ("ima: refactor ima_init_policy()")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index eb7d99fbae2dbfc5d7ceaf4295d9bbdbab7ec7b9..24d8aa2cc8ed4a2e51ce2adc41bbc75d2bdf053b 100644 (file)
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -590,8 +590,14 @@ static void add_rules(struct ima_rule_entry *entries, int count,
 
                        list_add_tail(&entry->list, &ima_policy_rules);
                }
-               if (entries[i].action == APPRAISE)
-                       temp_ima_appraise |= ima_appraise_flag(entries[i].func);
+               if (entries[i].action == APPRAISE) {
+                       if (entries != build_appraise_rules)
+                               temp_ima_appraise |=
+                                       ima_appraise_flag(entries[i].func);
+                       else
+                               build_ima_appraise |=
+                                       ima_appraise_flag(entries[i].func);
+               }
        }
 }