mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 10:16:49 +07:00
903 lines
20 KiB
C
903 lines
20 KiB
C
#include "audit.h"
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#include <linux/inotify.h>
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#include <linux/namei.h>
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#include <linux/mount.h>
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struct audit_tree;
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struct audit_chunk;
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struct audit_tree {
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atomic_t count;
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int goner;
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struct audit_chunk *root;
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struct list_head chunks;
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struct list_head rules;
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struct list_head list;
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struct list_head same_root;
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struct rcu_head head;
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char pathname[];
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};
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struct audit_chunk {
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struct list_head hash;
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struct inotify_watch watch;
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struct list_head trees; /* with root here */
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int dead;
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int count;
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struct rcu_head head;
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struct node {
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struct list_head list;
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struct audit_tree *owner;
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unsigned index; /* index; upper bit indicates 'will prune' */
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} owners[];
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};
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static LIST_HEAD(tree_list);
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static LIST_HEAD(prune_list);
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/*
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* One struct chunk is attached to each inode of interest.
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* We replace struct chunk on tagging/untagging.
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* Rules have pointer to struct audit_tree.
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* Rules have struct list_head rlist forming a list of rules over
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* the same tree.
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* References to struct chunk are collected at audit_inode{,_child}()
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* time and used in AUDIT_TREE rule matching.
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* These references are dropped at the same time we are calling
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* audit_free_names(), etc.
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*
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* Cyclic lists galore:
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* tree.chunks anchors chunk.owners[].list hash_lock
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* tree.rules anchors rule.rlist audit_filter_mutex
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* chunk.trees anchors tree.same_root hash_lock
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* chunk.hash is a hash with middle bits of watch.inode as
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* a hash function. RCU, hash_lock
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*
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* tree is refcounted; one reference for "some rules on rules_list refer to
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* it", one for each chunk with pointer to it.
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*
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* chunk is refcounted by embedded inotify_watch.
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*
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* node.index allows to get from node.list to containing chunk.
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* MSB of that sucker is stolen to mark taggings that we might have to
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* revert - several operations have very unpleasant cleanup logics and
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* that makes a difference. Some.
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*/
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static struct inotify_handle *rtree_ih;
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static struct audit_tree *alloc_tree(const char *s)
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{
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struct audit_tree *tree;
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tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL);
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if (tree) {
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atomic_set(&tree->count, 1);
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tree->goner = 0;
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INIT_LIST_HEAD(&tree->chunks);
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INIT_LIST_HEAD(&tree->rules);
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INIT_LIST_HEAD(&tree->list);
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INIT_LIST_HEAD(&tree->same_root);
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tree->root = NULL;
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strcpy(tree->pathname, s);
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}
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return tree;
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}
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static inline void get_tree(struct audit_tree *tree)
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{
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atomic_inc(&tree->count);
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}
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static void __put_tree(struct rcu_head *rcu)
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{
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struct audit_tree *tree = container_of(rcu, struct audit_tree, head);
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kfree(tree);
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}
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static inline void put_tree(struct audit_tree *tree)
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{
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if (atomic_dec_and_test(&tree->count))
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call_rcu(&tree->head, __put_tree);
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}
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/* to avoid bringing the entire thing in audit.h */
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const char *audit_tree_path(struct audit_tree *tree)
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{
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return tree->pathname;
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}
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static struct audit_chunk *alloc_chunk(int count)
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{
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struct audit_chunk *chunk;
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size_t size;
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int i;
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size = offsetof(struct audit_chunk, owners) + count * sizeof(struct node);
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chunk = kzalloc(size, GFP_KERNEL);
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if (!chunk)
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return NULL;
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INIT_LIST_HEAD(&chunk->hash);
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INIT_LIST_HEAD(&chunk->trees);
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chunk->count = count;
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for (i = 0; i < count; i++) {
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INIT_LIST_HEAD(&chunk->owners[i].list);
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chunk->owners[i].index = i;
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}
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inotify_init_watch(&chunk->watch);
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return chunk;
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}
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static void __free_chunk(struct rcu_head *rcu)
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{
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struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);
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int i;
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for (i = 0; i < chunk->count; i++) {
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if (chunk->owners[i].owner)
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put_tree(chunk->owners[i].owner);
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}
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kfree(chunk);
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}
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static inline void free_chunk(struct audit_chunk *chunk)
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{
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call_rcu(&chunk->head, __free_chunk);
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}
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void audit_put_chunk(struct audit_chunk *chunk)
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{
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put_inotify_watch(&chunk->watch);
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}
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enum {HASH_SIZE = 128};
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static struct list_head chunk_hash_heads[HASH_SIZE];
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static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock);
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static inline struct list_head *chunk_hash(const struct inode *inode)
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{
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unsigned long n = (unsigned long)inode / L1_CACHE_BYTES;
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return chunk_hash_heads + n % HASH_SIZE;
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}
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/* hash_lock is held by caller */
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static void insert_hash(struct audit_chunk *chunk)
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{
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struct list_head *list = chunk_hash(chunk->watch.inode);
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list_add_rcu(&chunk->hash, list);
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}
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/* called under rcu_read_lock */
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struct audit_chunk *audit_tree_lookup(const struct inode *inode)
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{
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struct list_head *list = chunk_hash(inode);
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struct audit_chunk *p;
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list_for_each_entry_rcu(p, list, hash) {
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if (p->watch.inode == inode) {
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get_inotify_watch(&p->watch);
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return p;
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}
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}
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return NULL;
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}
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int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree)
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{
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int n;
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for (n = 0; n < chunk->count; n++)
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if (chunk->owners[n].owner == tree)
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return 1;
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return 0;
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}
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/* tagging and untagging inodes with trees */
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static void untag_chunk(struct audit_chunk *chunk, struct node *p)
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{
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struct audit_chunk *new;
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struct audit_tree *owner;
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int size = chunk->count - 1;
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int i, j;
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mutex_lock(&chunk->watch.inode->inotify_mutex);
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if (chunk->dead) {
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mutex_unlock(&chunk->watch.inode->inotify_mutex);
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return;
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}
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owner = p->owner;
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if (!size) {
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chunk->dead = 1;
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spin_lock(&hash_lock);
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list_del_init(&chunk->trees);
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if (owner->root == chunk)
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owner->root = NULL;
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list_del_init(&p->list);
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list_del_rcu(&chunk->hash);
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spin_unlock(&hash_lock);
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inotify_evict_watch(&chunk->watch);
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mutex_unlock(&chunk->watch.inode->inotify_mutex);
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put_inotify_watch(&chunk->watch);
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return;
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}
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new = alloc_chunk(size);
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if (!new)
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goto Fallback;
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if (inotify_clone_watch(&chunk->watch, &new->watch) < 0) {
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free_chunk(new);
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goto Fallback;
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}
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chunk->dead = 1;
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spin_lock(&hash_lock);
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list_replace_init(&chunk->trees, &new->trees);
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if (owner->root == chunk) {
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list_del_init(&owner->same_root);
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owner->root = NULL;
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}
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for (i = j = 0; i < size; i++, j++) {
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struct audit_tree *s;
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if (&chunk->owners[j] == p) {
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list_del_init(&p->list);
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i--;
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continue;
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}
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s = chunk->owners[j].owner;
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new->owners[i].owner = s;
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new->owners[i].index = chunk->owners[j].index - j + i;
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if (!s) /* result of earlier fallback */
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continue;
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get_tree(s);
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list_replace_init(&chunk->owners[i].list, &new->owners[j].list);
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}
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list_replace_rcu(&chunk->hash, &new->hash);
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list_for_each_entry(owner, &new->trees, same_root)
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owner->root = new;
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spin_unlock(&hash_lock);
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inotify_evict_watch(&chunk->watch);
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mutex_unlock(&chunk->watch.inode->inotify_mutex);
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put_inotify_watch(&chunk->watch);
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return;
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Fallback:
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// do the best we can
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spin_lock(&hash_lock);
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if (owner->root == chunk) {
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list_del_init(&owner->same_root);
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owner->root = NULL;
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}
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list_del_init(&p->list);
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p->owner = NULL;
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put_tree(owner);
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spin_unlock(&hash_lock);
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mutex_unlock(&chunk->watch.inode->inotify_mutex);
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}
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static int create_chunk(struct inode *inode, struct audit_tree *tree)
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{
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struct audit_chunk *chunk = alloc_chunk(1);
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if (!chunk)
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return -ENOMEM;
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if (inotify_add_watch(rtree_ih, &chunk->watch, inode, IN_IGNORED | IN_DELETE_SELF) < 0) {
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free_chunk(chunk);
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return -ENOSPC;
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}
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mutex_lock(&inode->inotify_mutex);
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spin_lock(&hash_lock);
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if (tree->goner) {
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spin_unlock(&hash_lock);
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chunk->dead = 1;
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inotify_evict_watch(&chunk->watch);
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mutex_unlock(&inode->inotify_mutex);
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put_inotify_watch(&chunk->watch);
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return 0;
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}
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chunk->owners[0].index = (1U << 31);
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chunk->owners[0].owner = tree;
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get_tree(tree);
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list_add(&chunk->owners[0].list, &tree->chunks);
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if (!tree->root) {
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tree->root = chunk;
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list_add(&tree->same_root, &chunk->trees);
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}
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insert_hash(chunk);
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spin_unlock(&hash_lock);
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mutex_unlock(&inode->inotify_mutex);
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return 0;
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}
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/* the first tagged inode becomes root of tree */
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static int tag_chunk(struct inode *inode, struct audit_tree *tree)
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{
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struct inotify_watch *watch;
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struct audit_tree *owner;
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struct audit_chunk *chunk, *old;
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struct node *p;
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int n;
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if (inotify_find_watch(rtree_ih, inode, &watch) < 0)
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return create_chunk(inode, tree);
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old = container_of(watch, struct audit_chunk, watch);
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/* are we already there? */
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spin_lock(&hash_lock);
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for (n = 0; n < old->count; n++) {
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if (old->owners[n].owner == tree) {
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spin_unlock(&hash_lock);
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put_inotify_watch(watch);
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return 0;
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}
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}
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spin_unlock(&hash_lock);
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chunk = alloc_chunk(old->count + 1);
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if (!chunk)
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return -ENOMEM;
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mutex_lock(&inode->inotify_mutex);
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if (inotify_clone_watch(&old->watch, &chunk->watch) < 0) {
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mutex_unlock(&inode->inotify_mutex);
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free_chunk(chunk);
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return -ENOSPC;
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}
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spin_lock(&hash_lock);
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if (tree->goner) {
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spin_unlock(&hash_lock);
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chunk->dead = 1;
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inotify_evict_watch(&chunk->watch);
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mutex_unlock(&inode->inotify_mutex);
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put_inotify_watch(&chunk->watch);
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return 0;
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}
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list_replace_init(&old->trees, &chunk->trees);
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for (n = 0, p = chunk->owners; n < old->count; n++, p++) {
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struct audit_tree *s = old->owners[n].owner;
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p->owner = s;
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p->index = old->owners[n].index;
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if (!s) /* result of fallback in untag */
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continue;
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get_tree(s);
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list_replace_init(&old->owners[n].list, &p->list);
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}
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p->index = (chunk->count - 1) | (1U<<31);
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p->owner = tree;
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get_tree(tree);
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list_add(&p->list, &tree->chunks);
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list_replace_rcu(&old->hash, &chunk->hash);
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list_for_each_entry(owner, &chunk->trees, same_root)
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owner->root = chunk;
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old->dead = 1;
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if (!tree->root) {
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tree->root = chunk;
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list_add(&tree->same_root, &chunk->trees);
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}
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spin_unlock(&hash_lock);
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inotify_evict_watch(&old->watch);
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mutex_unlock(&inode->inotify_mutex);
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put_inotify_watch(&old->watch);
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return 0;
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}
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static struct audit_chunk *find_chunk(struct node *p)
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{
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int index = p->index & ~(1U<<31);
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p -= index;
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return container_of(p, struct audit_chunk, owners[0]);
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}
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static void kill_rules(struct audit_tree *tree)
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{
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struct audit_krule *rule, *next;
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struct audit_entry *entry;
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struct audit_buffer *ab;
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list_for_each_entry_safe(rule, next, &tree->rules, rlist) {
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entry = container_of(rule, struct audit_entry, rule);
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list_del_init(&rule->rlist);
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if (rule->tree) {
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/* not a half-baked one */
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ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
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audit_log_format(ab, "op=remove rule dir=");
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audit_log_untrustedstring(ab, rule->tree->pathname);
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if (rule->filterkey) {
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audit_log_format(ab, " key=");
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audit_log_untrustedstring(ab, rule->filterkey);
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} else
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audit_log_format(ab, " key=(null)");
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audit_log_format(ab, " list=%d res=1", rule->listnr);
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audit_log_end(ab);
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rule->tree = NULL;
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list_del_rcu(&entry->list);
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call_rcu(&entry->rcu, audit_free_rule_rcu);
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}
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}
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}
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/*
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* finish killing struct audit_tree
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*/
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static void prune_one(struct audit_tree *victim)
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{
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spin_lock(&hash_lock);
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while (!list_empty(&victim->chunks)) {
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struct node *p;
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struct audit_chunk *chunk;
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p = list_entry(victim->chunks.next, struct node, list);
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chunk = find_chunk(p);
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get_inotify_watch(&chunk->watch);
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spin_unlock(&hash_lock);
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untag_chunk(chunk, p);
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put_inotify_watch(&chunk->watch);
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spin_lock(&hash_lock);
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}
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spin_unlock(&hash_lock);
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put_tree(victim);
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}
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/* trim the uncommitted chunks from tree */
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static void trim_marked(struct audit_tree *tree)
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{
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struct list_head *p, *q;
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spin_lock(&hash_lock);
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if (tree->goner) {
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spin_unlock(&hash_lock);
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return;
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}
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/* reorder */
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for (p = tree->chunks.next; p != &tree->chunks; p = q) {
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struct node *node = list_entry(p, struct node, list);
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q = p->next;
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if (node->index & (1U<<31)) {
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list_del_init(p);
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list_add(p, &tree->chunks);
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}
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}
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while (!list_empty(&tree->chunks)) {
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struct node *node;
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struct audit_chunk *chunk;
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node = list_entry(tree->chunks.next, struct node, list);
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/* have we run out of marked? */
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if (!(node->index & (1U<<31)))
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break;
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chunk = find_chunk(node);
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get_inotify_watch(&chunk->watch);
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spin_unlock(&hash_lock);
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untag_chunk(chunk, node);
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put_inotify_watch(&chunk->watch);
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spin_lock(&hash_lock);
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}
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if (!tree->root && !tree->goner) {
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tree->goner = 1;
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spin_unlock(&hash_lock);
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mutex_lock(&audit_filter_mutex);
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kill_rules(tree);
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list_del_init(&tree->list);
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mutex_unlock(&audit_filter_mutex);
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prune_one(tree);
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} else {
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spin_unlock(&hash_lock);
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}
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}
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/* called with audit_filter_mutex */
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int audit_remove_tree_rule(struct audit_krule *rule)
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{
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struct audit_tree *tree;
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tree = rule->tree;
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if (tree) {
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spin_lock(&hash_lock);
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list_del_init(&rule->rlist);
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if (list_empty(&tree->rules) && !tree->goner) {
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tree->root = NULL;
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list_del_init(&tree->same_root);
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tree->goner = 1;
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list_move(&tree->list, &prune_list);
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rule->tree = NULL;
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spin_unlock(&hash_lock);
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audit_schedule_prune();
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return 1;
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}
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rule->tree = NULL;
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spin_unlock(&hash_lock);
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return 1;
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}
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return 0;
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}
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void audit_trim_trees(void)
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{
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struct list_head cursor;
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mutex_lock(&audit_filter_mutex);
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list_add(&cursor, &tree_list);
|
|
while (cursor.next != &tree_list) {
|
|
struct audit_tree *tree;
|
|
struct path path;
|
|
struct vfsmount *root_mnt;
|
|
struct node *node;
|
|
struct list_head list;
|
|
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.mnt, path.dentry);
|
|
path_put(&path);
|
|
if (!root_mnt)
|
|
goto skip_it;
|
|
|
|
list_add_tail(&list, &root_mnt->mnt_list);
|
|
spin_lock(&hash_lock);
|
|
list_for_each_entry(node, &tree->chunks, list) {
|
|
struct audit_chunk *chunk = find_chunk(node);
|
|
struct inode *inode = chunk->watch.inode;
|
|
struct vfsmount *mnt;
|
|
node->index |= 1U<<31;
|
|
list_for_each_entry(mnt, &list, mnt_list) {
|
|
if (mnt->mnt_root->d_inode == inode) {
|
|
node->index &= ~(1U<<31);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
spin_unlock(&hash_lock);
|
|
trim_marked(tree);
|
|
put_tree(tree);
|
|
list_del_init(&list);
|
|
drop_collected_mounts(root_mnt);
|
|
skip_it:
|
|
mutex_lock(&audit_filter_mutex);
|
|
}
|
|
list_del(&cursor);
|
|
mutex_unlock(&audit_filter_mutex);
|
|
}
|
|
|
|
static int is_under(struct vfsmount *mnt, struct dentry *dentry,
|
|
struct path *path)
|
|
{
|
|
if (mnt != path->mnt) {
|
|
for (;;) {
|
|
if (mnt->mnt_parent == mnt)
|
|
return 0;
|
|
if (mnt->mnt_parent == path->mnt)
|
|
break;
|
|
mnt = mnt->mnt_parent;
|
|
}
|
|
dentry = mnt->mnt_mountpoint;
|
|
}
|
|
return is_subdir(dentry, path->dentry);
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
/* 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, *p;
|
|
struct list_head list;
|
|
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.mnt, path.dentry);
|
|
path_put(&path);
|
|
if (!mnt) {
|
|
err = -ENOMEM;
|
|
goto Err;
|
|
}
|
|
list_add_tail(&list, &mnt->mnt_list);
|
|
|
|
get_tree(tree);
|
|
list_for_each_entry(p, &list, mnt_list) {
|
|
err = tag_chunk(p->mnt_root->d_inode, tree);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
list_del(&list);
|
|
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 path;
|
|
struct vfsmount *tagged;
|
|
struct list_head list;
|
|
struct vfsmount *mnt;
|
|
struct dentry *dentry;
|
|
int err;
|
|
|
|
err = kern_path(new, 0, &path);
|
|
if (err)
|
|
return err;
|
|
tagged = collect_mounts(path.mnt, path.dentry);
|
|
path_put(&path);
|
|
if (!tagged)
|
|
return -ENOMEM;
|
|
|
|
err = kern_path(old, 0, &path);
|
|
if (err) {
|
|
drop_collected_mounts(tagged);
|
|
return err;
|
|
}
|
|
mnt = mntget(path.mnt);
|
|
dentry = dget(path.dentry);
|
|
path_put(&path);
|
|
|
|
if (dentry == tagged->mnt_root && dentry == mnt->mnt_root)
|
|
follow_up(&mnt, &dentry);
|
|
|
|
list_add_tail(&list, &tagged->mnt_list);
|
|
|
|
mutex_lock(&audit_filter_mutex);
|
|
list_add(&barrier, &tree_list);
|
|
list_add(&cursor, &barrier);
|
|
|
|
while (cursor.next != &tree_list) {
|
|
struct audit_tree *tree;
|
|
struct vfsmount *p;
|
|
|
|
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) {
|
|
put_tree(tree);
|
|
mutex_lock(&audit_filter_mutex);
|
|
continue;
|
|
}
|
|
|
|
spin_lock(&vfsmount_lock);
|
|
if (!is_under(mnt, dentry, &path)) {
|
|
spin_unlock(&vfsmount_lock);
|
|
path_put(&path);
|
|
put_tree(tree);
|
|
mutex_lock(&audit_filter_mutex);
|
|
continue;
|
|
}
|
|
spin_unlock(&vfsmount_lock);
|
|
path_put(&path);
|
|
|
|
list_for_each_entry(p, &list, mnt_list) {
|
|
failed = tag_chunk(p->mnt_root->d_inode, tree);
|
|
if (failed)
|
|
break;
|
|
}
|
|
|
|
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);
|
|
list_del(&list);
|
|
mutex_unlock(&audit_filter_mutex);
|
|
dput(dentry);
|
|
mntput(mnt);
|
|
drop_collected_mounts(tagged);
|
|
return failed;
|
|
}
|
|
|
|
/*
|
|
* That gets run when evict_chunk() ends up needing to kill audit_tree.
|
|
* Runs from a separate thread, with audit_cmd_mutex held.
|
|
*/
|
|
void audit_prune_trees(void)
|
|
{
|
|
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);
|
|
}
|
|
|
|
/*
|
|
* Here comes the stuff asynchronous to auditctl operations
|
|
*/
|
|
|
|
/* inode->inotify_mutex is locked */
|
|
static void evict_chunk(struct audit_chunk *chunk)
|
|
{
|
|
struct audit_tree *owner;
|
|
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);
|
|
kill_rules(owner);
|
|
list_move(&owner->list, &prune_list);
|
|
audit_schedule_prune();
|
|
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);
|
|
mutex_unlock(&audit_filter_mutex);
|
|
}
|
|
|
|
static void handle_event(struct inotify_watch *watch, u32 wd, u32 mask,
|
|
u32 cookie, const char *dname, struct inode *inode)
|
|
{
|
|
struct audit_chunk *chunk = container_of(watch, struct audit_chunk, watch);
|
|
|
|
if (mask & IN_IGNORED) {
|
|
evict_chunk(chunk);
|
|
put_inotify_watch(watch);
|
|
}
|
|
}
|
|
|
|
static void destroy_watch(struct inotify_watch *watch)
|
|
{
|
|
struct audit_chunk *chunk = container_of(watch, struct audit_chunk, watch);
|
|
free_chunk(chunk);
|
|
}
|
|
|
|
static const struct inotify_operations rtree_inotify_ops = {
|
|
.handle_event = handle_event,
|
|
.destroy_watch = destroy_watch,
|
|
};
|
|
|
|
static int __init audit_tree_init(void)
|
|
{
|
|
int i;
|
|
|
|
rtree_ih = inotify_init(&rtree_inotify_ops);
|
|
if (IS_ERR(rtree_ih))
|
|
audit_panic("cannot initialize inotify handle for rectree watches");
|
|
|
|
for (i = 0; i < HASH_SIZE; i++)
|
|
INIT_LIST_HEAD(&chunk_hash_heads[i]);
|
|
|
|
return 0;
|
|
}
|
|
__initcall(audit_tree_init);
|