[PATCH 2/7] ima: permit duplicate measurement list entries
From: Mimi Zohar <hidden>
Date: 2016-08-04 13:33:40
Also in:
kexec, lkml
Subsystem:
extended verification module (evm), integrity measurement architecture (ima), security subsystem, the rest · Maintainers:
Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
Measurements carried across kexec need to be added to the IMA measurement list, but should not prevent measurements of the newly booted kernel from being added to the measurement list. This patch adds support for allowing duplicate measurements. The "boot_aggregate" measurement entry is the delimiter between soft boots. Signed-off-by: Mimi Zohar <redacted> --- security/integrity/ima/ima_queue.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 4b1bb77..12d1b04 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c@@ -65,11 +65,12 @@ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value, } /* ima_add_template_entry helper function: - * - Add template entry to measurement list and hash table. + * - Add template entry to the measurement list and hash table, for + * all entries except those carried across kexec. * * (Called with ima_extend_list_mutex held.) */ -static int ima_add_digest_entry(struct ima_template_entry *entry) +static int ima_add_digest_entry(struct ima_template_entry *entry, int flags) { struct ima_queue_entry *qe; unsigned int key;
@@ -85,8 +86,10 @@ static int ima_add_digest_entry(struct ima_template_entry *entry) list_add_tail_rcu(&qe->later, &ima_measurements); atomic_long_inc(&ima_htable.len); - key = ima_hash_key(entry->digest); - hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]); + if (flags) { + key = ima_hash_key(entry->digest); + hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]); + } return 0; }
@@ -126,7 +129,7 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation, } } - result = ima_add_digest_entry(entry); + result = ima_add_digest_entry(entry, 1); if (result < 0) { audit_cause = "ENOMEM"; audit_info = 0;
@@ -155,7 +158,7 @@ int ima_restore_measurement_entry(struct ima_template_entry *entry) int result = 0; mutex_lock(&ima_extend_list_mutex); - result = ima_add_digest_entry(entry); + result = ima_add_digest_entry(entry, 0); mutex_unlock(&ima_extend_list_mutex); return result; }
--
2.1.0