From 219ca39427bf6c46c4e1473493e33bc00635e99b Mon Sep 17 00:00:00 2001
From: Richard Guy Briggs <rgb@redhat.com>
Date: Wed, 26 Mar 2014 07:26:47 -0400
Subject: [PATCH] audit: use union for audit_field values since they are
mutually exclusive
Since only one of val, uid, gid and lsm* are used at any given time, combine
them to reduce the size of the struct audit_field.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
---
include/linux/audit.h | 14 +++++++++-----
kernel/auditfilter.c | 29 ++++++++++++++++++++---------
2 files changed, 29 insertions(+), 14 deletions(-)
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 1ae00891aff9b..36dffeccebdbe 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -66,12 +66,16 @@ struct audit_krule {
struct audit_field {
u32 type;
- u32 val;
- kuid_t uid;
- kgid_t gid;
+ union {
+ u32 val;
+ kuid_t uid;
+ kgid_t gid;
+ struct {
+ char *lsm_str;
+ void *lsm_rule;
+ };
+ };
u32 op;
- char *lsm_str;
- void *lsm_rule;
};
extern int is_audit_feature_set(int which);
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index b65a138250b8d..40ed9813d4b28 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -71,6 +71,24 @@ static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
DEFINE_MUTEX(audit_filter_mutex);
+static void audit_free_lsm_field(struct audit_field *f)
+{
+ switch (f->type) {
+ case AUDIT_SUBJ_USER:
+ case AUDIT_SUBJ_ROLE:
+ case AUDIT_SUBJ_TYPE:
+ case AUDIT_SUBJ_SEN:
+ case AUDIT_SUBJ_CLR:
+ case AUDIT_OBJ_USER:
+ case AUDIT_OBJ_ROLE:
+ case AUDIT_OBJ_TYPE:
+ case AUDIT_OBJ_LEV_LOW:
+ case AUDIT_OBJ_LEV_HIGH:
+ kfree(f->lsm_str);
+ security_audit_rule_free(f->lsm_rule);
+ }
+}
+
static inline void audit_free_rule(struct audit_entry *e)
{
int i;
@@ -80,11 +98,8 @@ static inline void audit_free_rule(struct audit_entry *e)
if (erule->watch)
audit_put_watch(erule->watch);
if (erule->fields)
- for (i = 0; i < erule->field_count; i++) {
- struct audit_field *f = &erule->fields[i];
- kfree(f->lsm_str);
- security_audit_rule_free(f->lsm_rule);
- }
+ for (i = 0; i < erule->field_count; i++)
+ audit_free_lsm_field(&erule->fields[i]);
kfree(erule->fields);
kfree(erule->filterkey);
kfree(e);
@@ -422,10 +437,6 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
f->type = data->fields[i];
f->val = data->values[i];
- f->uid = INVALID_UID;
- f->gid = INVALID_GID;
- f->lsm_str = NULL;
- f->lsm_rule = NULL;
/* Support legacy tests for a valid loginuid */
if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) {