SmartisanOS_Kernel_Source/kernel/audit_tree.c at master · hhjack/SmartisanOS_Kernel_Source · GitHub

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#include "audit.h"

#include <linux/fsnotify_backend.h>

#include <linux/namei.h>

#include <linux/mount.h>

#include <linux/kthread.h>

#include <linux/slab.h>

struct audit_tree;

struct audit_chunk;

struct audit_tree {

atomic_t count;

int goner;

struct audit_chunk *root;

struct list_head chunks;

struct list_head rules;

struct list_head list;

struct list_head same_root;

struct rcu_head head;

char pathname[];

};

struct audit_chunk {

struct list_head hash;

struct fsnotify_mark mark;

struct list_head trees; /* with root here */

int dead;

int count;

atomic_long_t refs;

struct rcu_head head;

struct node {

struct list_head list;

struct audit_tree *owner;

unsigned index; /* index; upper bit indicates 'will prune' */

} owners[];

};

static LIST_HEAD(tree_list);

static LIST_HEAD(prune_list);

* One struct chunk is attached to each inode of interest.

* We replace struct chunk on tagging/untagging.

* Rules have pointer to struct audit_tree.

* Rules have struct list_head rlist forming a list of rules over

* the same tree.

* References to struct chunk are collected at audit_inode{,_child}()

* time and used in AUDIT_TREE rule matching.

* These references are dropped at the same time we are calling

* audit_free_names(), etc.

* Cyclic lists galore:

* tree.chunks anchors chunk.owners[].list hash_lock

* tree.rules anchors rule.rlist audit_filter_mutex

* chunk.trees anchors tree.same_root hash_lock

* chunk.hash is a hash with middle bits of watch.inode as

* a hash function. RCU, hash_lock

* tree is refcounted; one reference for "some rules on rules_list refer to

* it", one for each chunk with pointer to it.

* chunk is refcounted by embedded fsnotify_mark + .refs (non-zero refcount

* of watch contributes 1 to .refs).

* node.index allows to get from node.list to containing chunk.

* MSB of that sucker is stolen to mark taggings that we might have to

* revert - several operations have very unpleasant cleanup logics and

* that makes a difference. Some.

static struct fsnotify_group *audit_tree_group;

static struct audit_tree *alloc_tree(const char *s)

{

struct audit_tree *tree;

tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL);

if (tree) {

atomic_set(&tree->count, 1);

tree->goner = 0;

INIT_LIST_HEAD(&tree->chunks);

INIT_LIST_HEAD(&tree->rules);

INIT_LIST_HEAD(&tree->list);

INIT_LIST_HEAD(&tree->same_root);

tree->root = NULL;

strcpy(tree->pathname, s);

}

return tree;

}

static inline void get_tree(struct audit_tree *tree)

{

atomic_inc(&tree->count);

}

static inline void put_tree(struct audit_tree *tree)

{

if (atomic_dec_and_test(&tree->count))

kfree_rcu(tree, head);

}

/* to avoid bringing the entire thing in audit.h */

const char *audit_tree_path(struct audit_tree *tree)

{

return tree->pathname;

}

static void free_chunk(struct audit_chunk *chunk)

{

int i;

for (i = 0; i < chunk->count; i++) {

if (chunk->owners[i].owner)

put_tree(chunk->owners[i].owner);

}

kfree(chunk);

}

void audit_put_chunk(struct audit_chunk *chunk)

{

if (atomic_long_dec_and_test(&chunk->refs))

free_chunk(chunk);

}

static void __put_chunk(struct rcu_head *rcu)

{

struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);

audit_put_chunk(chunk);

}

static void audit_tree_destroy_watch(struct fsnotify_mark *entry)

{

struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark);

call_rcu(&chunk->head, __put_chunk);

}

static struct audit_chunk *alloc_chunk(int count)

{

struct audit_chunk *chunk;

size_t size;

int i;

size = offsetof(struct audit_chunk, owners) + count * sizeof(struct node);

chunk = kzalloc(size, GFP_KERNEL);

if (!chunk)

return NULL;

INIT_LIST_HEAD(&chunk->hash);

INIT_LIST_HEAD(&chunk->trees);

chunk->count = count;

atomic_long_set(&chunk->refs, 1);

for (i = 0; i < count; i++) {

INIT_LIST_HEAD(&chunk->owners[i].list);

chunk->owners[i].index = i;

}

fsnotify_init_mark(&chunk->mark, audit_tree_destroy_watch);

return chunk;

}

enum {HASH_SIZE = 128};

static struct list_head chunk_hash_heads[HASH_SIZE];

static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock);

static inline struct list_head *chunk_hash(const struct inode *inode)

{

unsigned long n = (unsigned long)inode / L1_CACHE_BYTES;

return chunk_hash_heads + n % HASH_SIZE;

}

/* hash_lock & entry->lock is held by caller */

static void insert_hash(struct audit_chunk *chunk)

{

struct fsnotify_mark *entry = &chunk->mark;

struct list_head *list;

if (!entry->i.inode)

return;

list = chunk_hash(entry->i.inode);

list_add_rcu(&chunk->hash, list);

}

/* called under rcu_read_lock */

struct audit_chunk *audit_tree_lookup(const struct inode *inode)

{

struct list_head *list = chunk_hash(inode);

struct audit_chunk *p;

list_for_each_entry_rcu(p, list, hash) {

/* mark.inode may have gone NULL, but who cares? */

if (p->mark.i.inode == inode) {

atomic_long_inc(&p->refs);

return p;

}

return NULL;

}

int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree)

{

int n;

for (n = 0; n < chunk->count; n++)

if (chunk->owners[n].owner == tree)

return 1;

return 0;

}

/* tagging and untagging inodes with trees */

static struct audit_chunk *find_chunk(struct node *p)

{

int index = p->index & ~(1U<<31);

p -= index;

return container_of(p, struct audit_chunk, owners[0]);

}

static void untag_chunk(struct node *p)

{

struct audit_chunk *chunk = find_chunk(p);

struct fsnotify_mark *entry = &chunk->mark;

struct audit_chunk *new = NULL;

struct audit_tree *owner;

int size = chunk->count - 1;

int i, j;

fsnotify_get_mark(entry);

spin_unlock(&hash_lock);

if (size)

new = alloc_chunk(size);

spin_lock(&entry->lock);

if (chunk->dead || !entry->i.inode) {

spin_unlock(&entry->lock);

if (new)

free_chunk(new);

goto out;

}

owner = p->owner;

if (!size) {

chunk->dead = 1;

spin_lock(&hash_lock);

list_del_init(&chunk->trees);

if (owner->root == chunk)

owner->root = NULL;

list_del_init(&p->list);

list_del_rcu(&chunk->hash);

spin_unlock(&hash_lock);

spin_unlock(&entry->lock);

fsnotify_destroy_mark(entry);

fsnotify_put_mark(entry);

goto out;

}

if (!new)

goto Fallback;

fsnotify_duplicate_mark(&new->mark, entry);

if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) {

free_chunk(new);

goto Fallback;

}

chunk->dead = 1;

spin_lock(&hash_lock);

list_replace_init(&chunk->trees, &new->trees);

if (owner->root == chunk) {

list_del_init(&owner->same_root);

owner->root = NULL;

}

for (i = j = 0; j <= size; i++, j++) {

struct audit_tree *s;

if (&chunk->owners[j] == p) {

list_del_init(&p->list);

i--;

continue;

}

s = chunk->owners[j].owner;

new->owners[i].owner = s;

new->owners[i].index = chunk->owners[j].index - j + i;

if (!s) /* result of earlier fallback */

continue;

get_tree(s);

list_replace_init(&chunk->owners[j].list, &new->owners[i].list);

}

list_replace_rcu(&chunk->hash, &new->hash);

list_for_each_entry(owner, &new->trees, same_root)

owner->root = new;

spin_unlock(&hash_lock);

spin_unlock(&entry->lock);

fsnotify_destroy_mark(entry);

fsnotify_put_mark(entry);

goto out;

Fallback:

// do the best we can

spin_lock(&hash_lock);

if (owner->root == chunk) {

list_del_init(&owner->same_root);

owner->root = NULL;

}

list_del_init(&p->list);

p->owner = NULL;

put_tree(owner);

spin_unlock(&hash_lock);

spin_unlock(&entry->lock);

out:

fsnotify_put_mark(entry);

spin_lock(&hash_lock);

}

static int create_chunk(struct inode *inode, struct audit_tree *tree)

{

struct fsnotify_mark *entry;

struct audit_chunk *chunk = alloc_chunk(1);

if (!chunk)

return -ENOMEM;

entry = &chunk->mark;

if (fsnotify_add_mark(entry, audit_tree_group, inode, NULL, 0)) {

free_chunk(chunk);

return -ENOSPC;

}

spin_lock(&entry->lock);

spin_lock(&hash_lock);

if (tree->goner) {

spin_unlock(&hash_lock);

chunk->dead = 1;

spin_unlock(&entry->lock);

fsnotify_destroy_mark(entry);

fsnotify_put_mark(entry);

return 0;

}

chunk->owners[0].index = (1U << 31);

chunk->owners[0].owner = tree;

get_tree(tree);

list_add(&chunk->owners[0].list, &tree->chunks);

if (!tree->root) {

tree->root = chunk;

list_add(&tree->same_root, &chunk->trees);

}

insert_hash(chunk);

spin_unlock(&hash_lock);

spin_unlock(&entry->lock);

return 0;

}

/* the first tagged inode becomes root of tree */

static int tag_chunk(struct inode *inode, struct audit_tree *tree)

{

struct fsnotify_mark *old_entry, *chunk_entry;

struct audit_tree *owner;

struct audit_chunk *chunk, *old;

struct node *p;

int n;

old_entry = fsnotify_find_inode_mark(audit_tree_group, inode);

if (!old_entry)

return create_chunk(inode, tree);

old = container_of(old_entry, struct audit_chunk, mark);

/* are we already there? */

spin_lock(&hash_lock);

for (n = 0; n < old->count; n++) {

if (old->owners[n].owner == tree) {

spin_unlock(&hash_lock);

fsnotify_put_mark(old_entry);

return 0;

}

spin_unlock(&hash_lock);

chunk = alloc_chunk(old->count + 1);

if (!chunk) {

fsnotify_put_mark(old_entry);

return -ENOMEM;

}

chunk_entry = &chunk->mark;

spin_lock(&old_entry->lock);

if (!old_entry->i.inode) {

/* old_entry is being shot, lets just lie */

spin_unlock(&old_entry->lock);

fsnotify_put_mark(old_entry);

free_chunk(chunk);

return -ENOENT;

}

fsnotify_duplicate_mark(chunk_entry, old_entry);

if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->i.inode, NULL, 1)) {

spin_unlock(&old_entry->lock);

free_chunk(chunk);

fsnotify_put_mark(old_entry);

return -ENOSPC;

}

/* even though we hold old_entry->lock, this is safe since chunk_entry->lock could NEVER have been grabbed before */

spin_lock(&chunk_entry->lock);

spin_lock(&hash_lock);

/* we now hold old_entry->lock, chunk_entry->lock, and hash_lock */

if (tree->goner) {

spin_unlock(&hash_lock);

chunk->dead = 1;

spin_unlock(&chunk_entry->lock);

spin_unlock(&old_entry->lock);

fsnotify_destroy_mark(chunk_entry);

fsnotify_put_mark(chunk_entry);

fsnotify_put_mark(old_entry);

return 0;

}

list_replace_init(&old->trees, &chunk->trees);

for (n = 0, p = chunk->owners; n < old->count; n++, p++) {

struct audit_tree *s = old->owners[n].owner;

p->owner = s;

p->index = old->owners[n].index;

if (!s) /* result of fallback in untag */

continue;

get_tree(s);

list_replace_init(&old->owners[n].list, &p->list);

}

p->index = (chunk->count - 1) | (1U<<31);

p->owner = tree;

get_tree(tree);

list_add(&p->list, &tree->chunks);

list_replace_rcu(&old->hash, &chunk->hash);

list_for_each_entry(owner, &chunk->trees, same_root)

owner->root = chunk;

old->dead = 1;

if (!tree->root) {

tree->root = chunk;

list_add(&tree->same_root, &chunk->trees);

}

spin_unlock(&hash_lock);

spin_unlock(&chunk_entry->lock);

spin_unlock(&old_entry->lock);

fsnotify_destroy_mark(old_entry);

fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */

fsnotify_put_mark(old_entry); /* and kill it */

return 0;

}

static void kill_rules(struct audit_tree *tree)

{

struct audit_krule *rule, *next;

struct audit_entry *entry;

struct audit_buffer *ab;

list_for_each_entry_safe(rule, next, &tree->rules, rlist) {

entry = container_of(rule, struct audit_entry, rule);

list_del_init(&rule->rlist);

if (rule->tree) {

/* not a half-baked one */

ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);

audit_log_format(ab, "op=");

audit_log_string(ab, "remove rule");

audit_log_format(ab, " dir=");

audit_log_untrustedstring(ab, rule->tree->pathname);

audit_log_key(ab, rule->filterkey);

audit_log_format(ab, " list=%d res=1", rule->listnr);

audit_log_end(ab);

rule->tree = NULL;

list_del_rcu(&entry->list);

list_del(&entry->rule.list);

call_rcu(&entry->rcu, audit_free_rule_rcu);

}

* finish killing struct audit_tree

static void prune_one(struct audit_tree *victim)

{

spin_lock(&hash_lock);

while (!list_empty(&victim->chunks)) {

struct node *p;

p = list_entry(victim->chunks.next, struct node, list);

untag_chunk(p);

}

spin_unlock(&hash_lock);

put_tree(victim);

}

/* trim the uncommitted chunks from tree */

static void trim_marked(struct audit_tree *tree)

{

struct list_head *p, *q;

spin_lock(&hash_lock);

if (tree->goner) {

spin_unlock(&hash_lock);

return;

}

/* reorder */

for (p = tree->chunks.next; p != &tree->chunks; p = q) {

struct node *node = list_entry(p, struct node, list);

q = p->next;

if (node->index & (1U<<31)) {

list_del_init(p);

list_add(p, &tree->chunks);

}

while (!list_empty(&tree->chunks)) {

struct node *node;

node = list_entry(tree->chunks.next, struct node, list);

/* have we run out of marked? */

if (!(node->index & (1U<<31)))

break;

untag_chunk(node);

}

if (!tree->root && !tree->goner) {

tree->goner = 1;

spin_unlock(&hash_lock);

mutex_lock(&audit_filter_mutex);

kill_rules(tree);

list_del_init(&tree->list);

mutex_unlock(&audit_filter_mutex);

prune_one(tree);

} else {

spin_unlock(&hash_lock);

}

static void audit_schedule_prune(void);

/* called with audit_filter_mutex */

int audit_remove_tree_rule(struct audit_krule *rule)

{

struct audit_tree *tree;

tree = rule->tree;

if (tree) {

spin_lock(&hash_lock);

list_del_init(&rule->rlist);

if (list_empty(&tree->rules) && !tree->goner) {

tree->root = NULL;

list_del_init(&tree->same_root);

tree->goner = 1;

list_move(&tree->list, &prune_list);

rule->tree = NULL;

spin_unlock(&hash_lock);

audit_schedule_prune();

return 1;

}

rule->tree = NULL;

spin_unlock(&hash_lock);

return 1;

}

return 0;

}

static int compare_root(struct vfsmount *mnt, void *arg)

{

return mnt->mnt_root->d_inode == arg;

}

void audit_trim_trees(void)

{

struct list_head cursor;

mutex_lock(&audit_filter_mutex);

list_add(&cursor, &tree_list);

while (cursor.next != &tree_list) {

struct audit_tree *tree;

struct path path;

struct vfsmount *root_mnt;

struct node *node;

int err;

tree = container_of(cursor.next, struct audit_tree, list);

get_tree(tree);

list_del(&cursor);

list_add(&cursor, &tree->list);

mutex_unlock(&audit_filter_mutex);

err = kern_path(tree->pathname, 0, &path);

if (err)

goto skip_it;

root_mnt = collect_mounts(&path);

path_put(&path);

if (!root_mnt)

goto skip_it;

spin_lock(&hash_lock);

list_for_each_entry(node, &tree->chunks, list) {

struct audit_chunk *chunk = find_chunk(node);

/* this could be NULL if the watch is dying else where... */

struct inode *inode = chunk->mark.i.inode;

node->index |= 1U<<31;

if (iterate_mounts(compare_root, inode, root_mnt))

node->index &= ~(1U<<31);

}

spin_unlock(&hash_lock);

trim_marked(tree);

put_tree(tree);

drop_collected_mounts(root_mnt);

skip_it:

mutex_lock(&audit_filter_mutex);

}

list_del(&cursor);

mutex_unlock(&audit_filter_mutex);

}

int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op)

{

if (pathname[0] != '/' ||

rule->listnr != AUDIT_FILTER_EXIT ||

op != Audit_equal ||

rule->inode_f || rule->watch || rule->tree)

return -EINVAL;

rule->tree = alloc_tree(pathname);

if (!rule->tree)

return -ENOMEM;

return 0;

}

void audit_put_tree(struct audit_tree *tree)

{

put_tree(tree);

}

static int tag_mount(struct vfsmount *mnt, void *arg)

{

return tag_chunk(mnt->mnt_root->d_inode, arg);

}

/* called with audit_filter_mutex */

int audit_add_tree_rule(struct audit_krule *rule)

{

struct audit_tree *seed = rule->tree, *tree;

struct path path;

struct vfsmount *mnt;

int err;

list_for_each_entry(tree, &tree_list, list) {

if (!strcmp(seed->pathname, tree->pathname)) {

put_tree(seed);

rule->tree = tree;

list_add(&rule->rlist, &tree->rules);

return 0;

}

tree = seed;

list_add(&tree->list, &tree_list);

list_add(&rule->rlist, &tree->rules);

/* do not set rule->tree yet */

mutex_unlock(&audit_filter_mutex);

err = kern_path(tree->pathname, 0, &path);

if (err)

goto Err;

mnt = collect_mounts(&path);

path_put(&path);

if (!mnt) {

err = -ENOMEM;

goto Err;

}

get_tree(tree);

err = iterate_mounts(tag_mount, tree, mnt);

drop_collected_mounts(mnt);

if (!err) {

struct node *node;

spin_lock(&hash_lock);

list_for_each_entry(node, &tree->chunks, list)

node->index &= ~(1U<<31);

spin_unlock(&hash_lock);

} else {

trim_marked(tree);

goto Err;

}

mutex_lock(&audit_filter_mutex);

if (list_empty(&rule->rlist)) {

put_tree(tree);

return -ENOENT;

}

rule->tree = tree;

put_tree(tree);

return 0;

Err:

mutex_lock(&audit_filter_mutex);

list_del_init(&tree->list);

list_del_init(&tree->rules);

put_tree(tree);

return err;

}

int audit_tag_tree(char *old, char *new)

{

struct list_head cursor, barrier;

int failed = 0;

struct path path1, path2;

struct vfsmount *tagged;

int err;

err = kern_path(new, 0, &path2);

if (err)

return err;

tagged = collect_mounts(&path2);

path_put(&path2);

if (!tagged)

return -ENOMEM;

err = kern_path(old, 0, &path1);

if (err) {

drop_collected_mounts(tagged);

return err;

}

mutex_lock(&audit_filter_mutex);

list_add(&barrier, &tree_list);

list_add(&cursor, &barrier);

while (cursor.next != &tree_list) {

struct audit_tree *tree;

int good_one = 0;

tree = container_of(cursor.next, struct audit_tree, list);

get_tree(tree);

list_del(&cursor);

list_add(&cursor, &tree->list);

mutex_unlock(&audit_filter_mutex);

err = kern_path(tree->pathname, 0, &path2);

if (!err) {

good_one = path_is_under(&path1, &path2);

path_put(&path2);

}

if (!good_one) {

put_tree(tree);

mutex_lock(&audit_filter_mutex);

continue;

}

failed = iterate_mounts(tag_mount, tree, tagged);

if (failed) {

put_tree(tree);

mutex_lock(&audit_filter_mutex);

break;

}

mutex_lock(&audit_filter_mutex);

spin_lock(&hash_lock);

if (!tree->goner) {

list_del(&tree->list);

list_add(&tree->list, &tree_list);

}

spin_unlock(&hash_lock);

put_tree(tree);

}

while (barrier.prev != &tree_list) {

struct audit_tree *tree;

tree = container_of(barrier.prev, struct audit_tree, list);

get_tree(tree);

list_del(&tree->list);

list_add(&tree->list, &barrier);

mutex_unlock(&audit_filter_mutex);

if (!failed) {

struct node *node;

spin_lock(&hash_lock);

list_for_each_entry(node, &tree->chunks, list)

node->index &= ~(1U<<31);

spin_unlock(&hash_lock);

} else {

trim_marked(tree);

}

put_tree(tree);

mutex_lock(&audit_filter_mutex);

}

list_del(&barrier);

list_del(&cursor);

mutex_unlock(&audit_filter_mutex);

path_put(&path1);

drop_collected_mounts(tagged);

return failed;

}

* That gets run when evict_chunk() ends up needing to kill audit_tree.

* Runs from a separate thread.

static int prune_tree_thread(void *unused)

{

mutex_lock(&audit_cmd_mutex);

mutex_lock(&audit_filter_mutex);

while (!list_empty(&prune_list)) {

struct audit_tree *victim;

victim = list_entry(prune_list.next, struct audit_tree, list);

list_del_init(&victim->list);

mutex_unlock(&audit_filter_mutex);

prune_one(victim);

mutex_lock(&audit_filter_mutex);

}

mutex_unlock(&audit_filter_mutex);

mutex_unlock(&audit_cmd_mutex);

return 0;

}

static void audit_schedule_prune(void)

{

kthread_run(prune_tree_thread, NULL, "audit_prune_tree");

}

* ... and that one is done if evict_chunk() decides to delay until the end

* of syscall. Runs synchronously.

void audit_kill_trees(struct list_head *list)

{

mutex_lock(&audit_cmd_mutex);

mutex_lock(&audit_filter_mutex);

while (!list_empty(list)) {

struct audit_tree *victim;

victim = list_entry(list->next, struct audit_tree, list);

kill_rules(victim);

list_del_init(&victim->list);

mutex_unlock(&audit_filter_mutex);

prune_one(victim);

mutex_lock(&audit_filter_mutex);

}

mutex_unlock(&audit_filter_mutex);

mutex_unlock(&audit_cmd_mutex);

}

* Here comes the stuff asynchronous to auditctl operations

static void evict_chunk(struct audit_chunk *chunk)

{

struct audit_tree *owner;

struct list_head *postponed = audit_killed_trees();

int need_prune = 0;

int n;

if (chunk->dead)

return;

chunk->dead = 1;

mutex_lock(&audit_filter_mutex);

spin_lock(&hash_lock);

while (!list_empty(&chunk->trees)) {

owner = list_entry(chunk->trees.next,

struct audit_tree, same_root);

owner->goner = 1;

owner->root = NULL;

list_del_init(&owner->same_root);

spin_unlock(&hash_lock);

if (!postponed) {

kill_rules(owner);

list_move(&owner->list, &prune_list);

need_prune = 1;

} else {

list_move(&owner->list, postponed);

}

spin_lock(&hash_lock);

}

list_del_rcu(&chunk->hash);

for (n = 0; n < chunk->count; n++)

list_del_init(&chunk->owners[n].list);

spin_unlock(&hash_lock);

if (need_prune)

audit_schedule_prune();

mutex_unlock(&audit_filter_mutex);

}

static int audit_tree_handle_event(struct fsnotify_group *group,

struct fsnotify_mark *inode_mark,

struct fsnotify_mark *vfsmonut_mark,

struct fsnotify_event *event)

{

BUG();

return -EOPNOTSUPP;

}

static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify_group *group)

{

struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark);

evict_chunk(chunk);

fsnotify_put_mark(entry);

}

static bool audit_tree_send_event(struct fsnotify_group *group, struct inode *inode,

struct fsnotify_mark *inode_mark,

struct fsnotify_mark *vfsmount_mark,

__u32 mask, void *data, int data_type)

{

return false;

}

static const struct fsnotify_ops audit_tree_ops = {

.handle_event = audit_tree_handle_event,

.should_send_event = audit_tree_send_event,

.free_group_priv = NULL,

.free_event_priv = NULL,

.freeing_mark = audit_tree_freeing_mark,

};

static int __init audit_tree_init(void)

{

int i;

audit_tree_group = fsnotify_alloc_group(&audit_tree_ops);

if (IS_ERR(audit_tree_group))

audit_panic("cannot initialize fsnotify group for rectree watches");

for (i = 0; i < HASH_SIZE; i++)

INIT_LIST_HEAD(&chunk_hash_heads[i]);

return 0;

}

__initcall(audit_tree_init);

SmartisanOS_Kernel_Source/kernel/audit_tree.c at master · hhjack/SmartisanOS_Kernel_Source · GitHub

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