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Diffstat (limited to 'kernel/auditfilter.c')
-rw-r--r--kernel/auditfilter.c339
1 files changed, 172 insertions, 167 deletions
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index b7d354e2b0e..fbf24d121d9 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -86,6 +86,14 @@ struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
#error Fix audit_filter_list initialiser
#endif
};
+static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
+ LIST_HEAD_INIT(audit_rules_list[0]),
+ LIST_HEAD_INIT(audit_rules_list[1]),
+ LIST_HEAD_INIT(audit_rules_list[2]),
+ LIST_HEAD_INIT(audit_rules_list[3]),
+ LIST_HEAD_INIT(audit_rules_list[4]),
+ LIST_HEAD_INIT(audit_rules_list[5]),
+};
DEFINE_MUTEX(audit_filter_mutex);
@@ -244,7 +252,8 @@ static inline int audit_to_inode(struct audit_krule *krule,
struct audit_field *f)
{
if (krule->listnr != AUDIT_FILTER_EXIT ||
- krule->watch || krule->inode_f || krule->tree)
+ krule->watch || krule->inode_f || krule->tree ||
+ (f->op != Audit_equal && f->op != Audit_not_equal))
return -EINVAL;
krule->inode_f = f;
@@ -262,7 +271,7 @@ static int audit_to_watch(struct audit_krule *krule, char *path, int len,
if (path[0] != '/' || path[len-1] == '/' ||
krule->listnr != AUDIT_FILTER_EXIT ||
- op & ~AUDIT_EQUAL ||
+ op != Audit_equal ||
krule->inode_f || krule->watch || krule->tree)
return -EINVAL;
@@ -412,12 +421,32 @@ exit_err:
return ERR_PTR(err);
}
+static u32 audit_ops[] =
+{
+ [Audit_equal] = AUDIT_EQUAL,
+ [Audit_not_equal] = AUDIT_NOT_EQUAL,
+ [Audit_bitmask] = AUDIT_BIT_MASK,
+ [Audit_bittest] = AUDIT_BIT_TEST,
+ [Audit_lt] = AUDIT_LESS_THAN,
+ [Audit_gt] = AUDIT_GREATER_THAN,
+ [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL,
+ [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL,
+};
+
+static u32 audit_to_op(u32 op)
+{
+ u32 n;
+ for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++)
+ ;
+ return n;
+}
+
+
/* Translate struct audit_rule to kernel's rule respresentation.
* Exists for backward compatibility with userspace. */
static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
{
struct audit_entry *entry;
- struct audit_field *ino_f;
int err = 0;
int i;
@@ -427,12 +456,28 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
for (i = 0; i < rule->field_count; i++) {
struct audit_field *f = &entry->rule.fields[i];
+ u32 n;
+
+ n = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS);
+
+ /* Support for legacy operators where
+ * AUDIT_NEGATE bit signifies != and otherwise assumes == */
+ if (n & AUDIT_NEGATE)
+ f->op = Audit_not_equal;
+ else if (!n)
+ f->op = Audit_equal;
+ else
+ f->op = audit_to_op(n);
+
+ entry->rule.vers_ops = (n & AUDIT_OPERATORS) ? 2 : 1;
- f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS);
f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS);
f->val = rule->values[i];
err = -EINVAL;
+ if (f->op == Audit_bad)
+ goto exit_free;
+
switch(f->type) {
default:
goto exit_free;
@@ -454,11 +499,8 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
case AUDIT_EXIT:
case AUDIT_SUCCESS:
/* bit ops are only useful on syscall args */
- if (f->op == AUDIT_BIT_MASK ||
- f->op == AUDIT_BIT_TEST) {
- err = -EINVAL;
+ if (f->op == Audit_bitmask || f->op == Audit_bittest)
goto exit_free;
- }
break;
case AUDIT_ARG0:
case AUDIT_ARG1:
@@ -467,11 +509,8 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
break;
/* arch is only allowed to be = or != */
case AUDIT_ARCH:
- if ((f->op != AUDIT_NOT_EQUAL) && (f->op != AUDIT_EQUAL)
- && (f->op != AUDIT_NEGATE) && (f->op)) {
- err = -EINVAL;
+ if (f->op != Audit_not_equal && f->op != Audit_equal)
goto exit_free;
- }
entry->rule.arch_f = f;
break;
case AUDIT_PERM:
@@ -488,33 +527,10 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
goto exit_free;
break;
}
-
- entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1;
-
- /* Support for legacy operators where
- * AUDIT_NEGATE bit signifies != and otherwise assumes == */
- if (f->op & AUDIT_NEGATE)
- f->op = AUDIT_NOT_EQUAL;
- else if (!f->op)
- f->op = AUDIT_EQUAL;
- else if (f->op == AUDIT_OPERATORS) {
- err = -EINVAL;
- goto exit_free;
- }
}
- ino_f = entry->rule.inode_f;
- if (ino_f) {
- switch(ino_f->op) {
- case AUDIT_NOT_EQUAL:
- entry->rule.inode_f = NULL;
- case AUDIT_EQUAL:
- break;
- default:
- err = -EINVAL;
- goto exit_free;
- }
- }
+ if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
+ entry->rule.inode_f = NULL;
exit_nofree:
return entry;
@@ -530,7 +546,6 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
{
int err = 0;
struct audit_entry *entry;
- struct audit_field *ino_f;
void *bufp;
size_t remain = datasz - sizeof(struct audit_rule_data);
int i;
@@ -546,11 +561,11 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
struct audit_field *f = &entry->rule.fields[i];
err = -EINVAL;
- if (!(data->fieldflags[i] & AUDIT_OPERATORS) ||
- data->fieldflags[i] & ~AUDIT_OPERATORS)
+
+ f->op = audit_to_op(data->fieldflags[i]);
+ if (f->op == Audit_bad)
goto exit_free;
- f->op = data->fieldflags[i] & AUDIT_OPERATORS;
f->type = data->fields[i];
f->val = data->values[i];
f->lsm_str = NULL;
@@ -662,18 +677,8 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
}
}
- ino_f = entry->rule.inode_f;
- if (ino_f) {
- switch(ino_f->op) {
- case AUDIT_NOT_EQUAL:
- entry->rule.inode_f = NULL;
- case AUDIT_EQUAL:
- break;
- default:
- err = -EINVAL;
- goto exit_free;
- }
- }
+ if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
+ entry->rule.inode_f = NULL;
exit_nofree:
return entry;
@@ -713,10 +718,10 @@ static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule)
rule->fields[i] = krule->fields[i].type;
if (krule->vers_ops == 1) {
- if (krule->fields[i].op & AUDIT_NOT_EQUAL)
+ if (krule->fields[i].op == Audit_not_equal)
rule->fields[i] |= AUDIT_NEGATE;
} else {
- rule->fields[i] |= krule->fields[i].op;
+ rule->fields[i] |= audit_ops[krule->fields[i].op];
}
}
for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i];
@@ -744,7 +749,7 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
struct audit_field *f = &krule->fields[i];
data->fields[i] = f->type;
- data->fieldflags[i] = f->op;
+ data->fieldflags[i] = audit_ops[f->op];
switch(f->type) {
case AUDIT_SUBJ_USER:
case AUDIT_SUBJ_ROLE:
@@ -919,6 +924,7 @@ static struct audit_entry *audit_dupe_rule(struct audit_krule *old,
new->action = old->action;
for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
new->mask[i] = old->mask[i];
+ new->prio = old->prio;
new->buflen = old->buflen;
new->inode_f = old->inode_f;
new->watch = NULL;
@@ -987,9 +993,8 @@ static void audit_update_watch(struct audit_parent *parent,
/* If the update involves invalidating rules, do the inode-based
* filtering now, so we don't omit records. */
- if (invalidating && current->audit_context &&
- audit_filter_inodes(current, current->audit_context) == AUDIT_RECORD_CONTEXT)
- audit_set_auditable(current->audit_context);
+ if (invalidating && current->audit_context)
+ audit_filter_inodes(current, current->audit_context);
nwatch = audit_dupe_watch(owatch);
if (IS_ERR(nwatch)) {
@@ -1007,12 +1012,15 @@ static void audit_update_watch(struct audit_parent *parent,
list_del_rcu(&oentry->list);
nentry = audit_dupe_rule(&oentry->rule, nwatch);
- if (IS_ERR(nentry))
+ if (IS_ERR(nentry)) {
+ list_del(&oentry->rule.list);
audit_panic("error updating watch, removing");
- else {
+ } else {
int h = audit_hash_ino((u32)ino);
list_add(&nentry->rule.rlist, &nwatch->rules);
list_add_rcu(&nentry->list, &audit_inode_hash[h]);
+ list_replace(&oentry->rule.list,
+ &nentry->rule.list);
}
call_rcu(&oentry->rcu, audit_free_rule_rcu);
@@ -1077,6 +1085,7 @@ static void audit_remove_parent_watches(struct audit_parent *parent)
audit_log_end(ab);
}
list_del(&r->rlist);
+ list_del(&r->list);
list_del_rcu(&e->list);
call_rcu(&e->rcu, audit_free_rule_rcu);
}
@@ -1094,20 +1103,24 @@ static void audit_inotify_unregister(struct list_head *in_list)
list_for_each_entry_safe(p, n, in_list, ilist) {
list_del(&p->ilist);
inotify_rm_watch(audit_ih, &p->wdata);
- /* the put matching the get in audit_do_del_rule() */
- put_inotify_watch(&p->wdata);
+ /* the unpin matching the pin in audit_do_del_rule() */
+ unpin_inotify_watch(&p->wdata);
}
}
/* Find an existing audit rule.
* Caller must hold audit_filter_mutex to prevent stale rule data. */
static struct audit_entry *audit_find_rule(struct audit_entry *entry,
- struct list_head *list)
+ struct list_head **p)
{
struct audit_entry *e, *found = NULL;
+ struct list_head *list;
int h;
- if (entry->rule.watch) {
+ if (entry->rule.inode_f) {
+ h = audit_hash_ino(entry->rule.inode_f->val);
+ *p = list = &audit_inode_hash[h];
+ } else if (entry->rule.watch) {
/* we don't know the inode number, so must walk entire hash */
for (h = 0; h < AUDIT_INODE_BUCKETS; h++) {
list = &audit_inode_hash[h];
@@ -1118,6 +1131,8 @@ static struct audit_entry *audit_find_rule(struct audit_entry *entry,
}
}
goto out;
+ } else {
+ *p = list = &audit_filter_list[entry->rule.listnr];
}
list_for_each_entry(e, list, list)
@@ -1258,15 +1273,17 @@ static int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp,
return ret;
}
+static u64 prio_low = ~0ULL/2;
+static u64 prio_high = ~0ULL/2 - 1;
+
/* Add rule to given filterlist if not a duplicate. */
-static inline int audit_add_rule(struct audit_entry *entry,
- struct list_head *list)
+static inline int audit_add_rule(struct audit_entry *entry)
{
struct audit_entry *e;
- struct audit_field *inode_f = entry->rule.inode_f;
struct audit_watch *watch = entry->rule.watch;
struct audit_tree *tree = entry->rule.tree;
struct nameidata *ndp = NULL, *ndw = NULL;
+ struct list_head *list;
int h, err;
#ifdef CONFIG_AUDITSYSCALL
int dont_count = 0;
@@ -1277,13 +1294,8 @@ static inline int audit_add_rule(struct audit_entry *entry,
dont_count = 1;
#endif
- if (inode_f) {
- h = audit_hash_ino(inode_f->val);
- list = &audit_inode_hash[h];
- }
-
mutex_lock(&audit_filter_mutex);
- e = audit_find_rule(entry, list);
+ e = audit_find_rule(entry, &list);
mutex_unlock(&audit_filter_mutex);
if (e) {
err = -EEXIST;
@@ -1319,10 +1331,22 @@ static inline int audit_add_rule(struct audit_entry *entry,
}
}
+ entry->rule.prio = ~0ULL;
+ if (entry->rule.listnr == AUDIT_FILTER_EXIT) {
+ if (entry->rule.flags & AUDIT_FILTER_PREPEND)
+ entry->rule.prio = ++prio_high;
+ else
+ entry->rule.prio = --prio_low;
+ }
+
if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
+ list_add(&entry->rule.list,
+ &audit_rules_list[entry->rule.listnr]);
list_add_rcu(&entry->list, list);
entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
} else {
+ list_add_tail(&entry->rule.list,
+ &audit_rules_list[entry->rule.listnr]);
list_add_tail_rcu(&entry->list, list);
}
#ifdef CONFIG_AUDITSYSCALL
@@ -1345,15 +1369,14 @@ error:
}
/* Remove an existing rule from filterlist. */
-static inline int audit_del_rule(struct audit_entry *entry,
- struct list_head *list)
+static inline int audit_del_rule(struct audit_entry *entry)
{
struct audit_entry *e;
- struct audit_field *inode_f = entry->rule.inode_f;
struct audit_watch *watch, *tmp_watch = entry->rule.watch;
struct audit_tree *tree = entry->rule.tree;
+ struct list_head *list;
LIST_HEAD(inotify_list);
- int h, ret = 0;
+ int ret = 0;
#ifdef CONFIG_AUDITSYSCALL
int dont_count = 0;
@@ -1363,13 +1386,8 @@ static inline int audit_del_rule(struct audit_entry *entry,
dont_count = 1;
#endif
- if (inode_f) {
- h = audit_hash_ino(inode_f->val);
- list = &audit_inode_hash[h];
- }
-
mutex_lock(&audit_filter_mutex);
- e = audit_find_rule(entry, list);
+ e = audit_find_rule(entry, &list);
if (!e) {
mutex_unlock(&audit_filter_mutex);
ret = -ENOENT;
@@ -1389,9 +1407,13 @@ static inline int audit_del_rule(struct audit_entry *entry,
/* Put parent on the inotify un-registration
* list. Grab a reference before releasing
* audit_filter_mutex, to be released in
- * audit_inotify_unregister(). */
- list_add(&parent->ilist, &inotify_list);
- get_inotify_watch(&parent->wdata);
+ * audit_inotify_unregister().
+ * If filesystem is going away, just leave
+ * the sucker alone, eviction will take
+ * care of it.
+ */
+ if (pin_inotify_watch(&parent->wdata))
+ list_add(&parent->ilist, &inotify_list);
}
}
}
@@ -1400,6 +1422,7 @@ static inline int audit_del_rule(struct audit_entry *entry,
audit_remove_tree_rule(&e->rule);
list_del_rcu(&e->list);
+ list_del(&e->rule.list);
call_rcu(&e->rcu, audit_free_rule_rcu);
#ifdef CONFIG_AUDITSYSCALL
@@ -1428,30 +1451,16 @@ out:
static void audit_list(int pid, int seq, struct sk_buff_head *q)
{
struct sk_buff *skb;
- struct audit_entry *entry;
+ struct audit_krule *r;
int i;
/* This is a blocking read, so use audit_filter_mutex instead of rcu
* iterator to sync with list writers. */
for (i=0; i<AUDIT_NR_FILTERS; i++) {
- list_for_each_entry(entry, &audit_filter_list[i], list) {
- struct audit_rule *rule;
-
- rule = audit_krule_to_rule(&entry->rule);
- if (unlikely(!rule))
- break;
- skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1,
- rule, sizeof(*rule));
- if (skb)
- skb_queue_tail(q, skb);
- kfree(rule);
- }
- }
- for (i = 0; i < AUDIT_INODE_BUCKETS; i++) {
- list_for_each_entry(entry, &audit_inode_hash[i], list) {
+ list_for_each_entry(r, &audit_rules_list[i], list) {
struct audit_rule *rule;
- rule = audit_krule_to_rule(&entry->rule);
+ rule = audit_krule_to_rule(r);
if (unlikely(!rule))
break;
skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1,
@@ -1470,30 +1479,16 @@ static void audit_list(int pid, int seq, struct sk_buff_head *q)
static void audit_list_rules(int pid, int seq, struct sk_buff_head *q)
{
struct sk_buff *skb;
- struct audit_entry *e;
+ struct audit_krule *r;
int i;
/* This is a blocking read, so use audit_filter_mutex instead of rcu
* iterator to sync with list writers. */
for (i=0; i<AUDIT_NR_FILTERS; i++) {
- list_for_each_entry(e, &audit_filter_list[i], list) {
- struct audit_rule_data *data;
-
- data = audit_krule_to_data(&e->rule);
- if (unlikely(!data))
- break;
- skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1,
- data, sizeof(*data) + data->buflen);
- if (skb)
- skb_queue_tail(q, skb);
- kfree(data);
- }
- }
- for (i=0; i< AUDIT_INODE_BUCKETS; i++) {
- list_for_each_entry(e, &audit_inode_hash[i], list) {
+ list_for_each_entry(r, &audit_rules_list[i], list) {
struct audit_rule_data *data;
- data = audit_krule_to_data(&e->rule);
+ data = audit_krule_to_data(r);
if (unlikely(!data))
break;
skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1,
@@ -1599,8 +1594,7 @@ int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
if (IS_ERR(entry))
return PTR_ERR(entry);
- err = audit_add_rule(entry,
- &audit_filter_list[entry->rule.listnr]);
+ err = audit_add_rule(entry);
audit_log_rule_change(loginuid, sessionid, sid, "add",
&entry->rule, !err);
@@ -1616,8 +1610,7 @@ int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
if (IS_ERR(entry))
return PTR_ERR(entry);
- err = audit_del_rule(entry,
- &audit_filter_list[entry->rule.listnr]);
+ err = audit_del_rule(entry);
audit_log_rule_change(loginuid, sessionid, sid, "remove",
&entry->rule, !err);
@@ -1630,28 +1623,29 @@ int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
return err;
}
-int audit_comparator(const u32 left, const u32 op, const u32 right)
+int audit_comparator(u32 left, u32 op, u32 right)
{
switch (op) {
- case AUDIT_EQUAL:
+ case Audit_equal:
return (left == right);
- case AUDIT_NOT_EQUAL:
+ case Audit_not_equal:
return (left != right);
- case AUDIT_LESS_THAN:
+ case Audit_lt:
return (left < right);
- case AUDIT_LESS_THAN_OR_EQUAL:
+ case Audit_le:
return (left <= right);
- case AUDIT_GREATER_THAN:
+ case Audit_gt:
return (left > right);
- case AUDIT_GREATER_THAN_OR_EQUAL:
+ case Audit_ge:
return (left >= right);
- case AUDIT_BIT_MASK:
+ case Audit_bitmask:
return (left & right);
- case AUDIT_BIT_TEST:
+ case Audit_bittest:
return ((left & right) == right);
+ default:
+ BUG();
+ return 0;
}
- BUG();
- return 0;
}
/* Compare given dentry name with last component in given path,
@@ -1774,6 +1768,43 @@ unlock_and_return:
return result;
}
+static int update_lsm_rule(struct audit_krule *r)
+{
+ struct audit_entry *entry = container_of(r, struct audit_entry, rule);
+ struct audit_entry *nentry;
+ struct audit_watch *watch;
+ struct audit_tree *tree;
+ int err = 0;
+
+ if (!security_audit_rule_known(r))
+ return 0;
+
+ watch = r->watch;
+ tree = r->tree;
+ nentry = audit_dupe_rule(r, watch);
+ if (IS_ERR(nentry)) {
+ /* save the first error encountered for the
+ * return value */
+ err = PTR_ERR(nentry);
+ audit_panic("error updating LSM filters");
+ if (watch)
+ list_del(&r->rlist);
+ list_del_rcu(&entry->list);
+ list_del(&r->list);
+ } else {
+ if (watch) {
+ list_add(&nentry->rule.rlist, &watch->rules);
+ list_del(&r->rlist);
+ } else if (tree)
+ list_replace_init(&r->rlist, &nentry->rule.rlist);
+ list_replace_rcu(&entry->list, &nentry->list);
+ list_replace(&r->list, &nentry->rule.list);
+ }
+ call_rcu(&entry->rcu, audit_free_rule_rcu);
+
+ return err;
+}
+
/* This function will re-initialize the lsm_rule field of all applicable rules.
* It will traverse the filter lists serarching for rules that contain LSM
* specific filter fields. When such a rule is found, it is copied, the
@@ -1781,45 +1812,19 @@ unlock_and_return:
* updated rule. */
int audit_update_lsm_rules(void)
{
- struct audit_entry *entry, *n, *nentry;
- struct audit_watch *watch;
- struct audit_tree *tree;
+ struct audit_krule *r, *n;
int i, err = 0;
/* audit_filter_mutex synchronizes the writers */
mutex_lock(&audit_filter_mutex);
for (i = 0; i < AUDIT_NR_FILTERS; i++) {
- list_for_each_entry_safe(entry, n, &audit_filter_list[i], list) {
- if (!security_audit_rule_known(&entry->rule))
- continue;
-
- watch = entry->rule.watch;
- tree = entry->rule.tree;
- nentry = audit_dupe_rule(&entry->rule, watch);
- if (IS_ERR(nentry)) {
- /* save the first error encountered for the
- * return value */
- if (!err)
- err = PTR_ERR(nentry);
- audit_panic("error updating LSM filters");
- if (watch)
- list_del(&entry->rule.rlist);
- list_del_rcu(&entry->list);
- } else {
- if (watch) {
- list_add(&nentry->rule.rlist,
- &watch->rules);
- list_del(&entry->rule.rlist);
- } else if (tree)
- list_replace_init(&entry->rule.rlist,
- &nentry->rule.rlist);
- list_replace_rcu(&entry->list, &nentry->list);
- }
- call_rcu(&entry->rcu, audit_free_rule_rcu);
+ list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
+ int res = update_lsm_rule(r);
+ if (!err)
+ err = res;
}
}
-
mutex_unlock(&audit_filter_mutex);
return err;