From 219ca39427bf6c46c4e1473493e33bc00635e99b Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs 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 --- 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 1ae0089..36dffec 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 b65a138..40ed981 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)) { -- 2.7.4