// SPDX-License-Identifier: GPL-2.0#include "audit.h"#include <linux/fsnotify_backend.h>#include <linux/namei.h>#include <linux/mount.h>#include <linux/kthread.h>#include <linux/refcount.h>#include <linux/slab.h> struct audit_tree;struct audit_chunk; struct audit_tree { refcount_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);static struct task_struct *prune_thread; /* * 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) { refcount_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){ refcount_inc(&tree->count);} static inline void put_tree(struct audit_tree *tree){ if (refcount_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_group); chunk->mark.mask = FS_IN_IGNORED; return chunk;} enum {HASH_SIZE = 128};static struct list_head chunk_hash_heads[HASH_SIZE];static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock); /* Function to return search key in our hash from inode. */static unsigned long inode_to_key(const struct inode *inode){ /* Use address pointed to by connector->obj as the key */ return (unsigned long)&inode->i_fsnotify_marks;} /* * Function to return search key in our hash from chunk. Key 0 is special and * should never be present in the hash. */static unsigned long chunk_to_key(struct audit_chunk *chunk){ /* * We have a reference to the mark so it should be attached to a * connector. */ if (WARN_ON_ONCE(!chunk->mark.connector)) return 0; return (unsigned long)chunk->mark.connector->obj;} static inline struct list_head *chunk_hash(unsigned long key){ unsigned long n = key / 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){ unsigned long key = chunk_to_key(chunk); struct list_head *list; if (!(chunk->mark.flags & FSNOTIFY_MARK_FLAG_ATTACHED)) return; list = chunk_hash(key); list_add_rcu(&chunk->hash, list);} /* called under rcu_read_lock */struct audit_chunk *audit_tree_lookup(const struct inode *inode){ unsigned long key = inode_to_key(inode); struct list_head *list = chunk_hash(key); struct audit_chunk *p; list_for_each_entry_rcu(p, list, hash) { if (chunk_to_key(p) == key) { atomic_long_inc(&p->refs); return p; } } return NULL;} bool 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 true; return false;} /* 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); mutex_lock(&entry->group->mark_mutex); spin_lock(&entry->lock); /* * mark_mutex protects mark from getting detached and thus also from * mark->connector->obj getting NULL. */ if (chunk->dead || !(entry->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) { spin_unlock(&entry->lock); mutex_unlock(&entry->group->mark_mutex); if (new) fsnotify_put_mark(&new->mark); 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); mutex_unlock(&entry->group->mark_mutex); fsnotify_destroy_mark(entry, audit_tree_group); goto out; } if (!new) goto Fallback; if (fsnotify_add_mark_locked(&new->mark, entry->connector->obj, FSNOTIFY_OBJ_TYPE_INODE, 1)) { fsnotify_put_mark(&new->mark); 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); mutex_unlock(&entry->group->mark_mutex); fsnotify_destroy_mark(entry, audit_tree_group); fsnotify_put_mark(&new->mark); /* drop initial reference */ 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); mutex_unlock(&entry->group->mark_mutex);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_inode_mark(entry, inode, 0)) { fsnotify_put_mark(entry); 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, audit_tree_group); 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); fsnotify_put_mark(entry); /* drop initial reference */ 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_mark(&inode->i_fsnotify_marks, audit_tree_group); 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; mutex_lock(&old_entry->group->mark_mutex); spin_lock(&old_entry->lock); /* * mark_mutex protects mark from getting detached and thus also from * mark->connector->obj getting NULL. */ if (!(old_entry->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) { /* old_entry is being shot, lets just lie */ spin_unlock(&old_entry->lock); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_put_mark(old_entry); fsnotify_put_mark(&chunk->mark); return -ENOENT; } if (fsnotify_add_mark_locked(chunk_entry, old_entry->connector->obj, FSNOTIFY_OBJ_TYPE_INODE, 1)) { spin_unlock(&old_entry->lock); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_put_mark(chunk_entry); 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); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_destroy_mark(chunk_entry, audit_tree_group); 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); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_destroy_mark(old_entry, audit_tree_group); fsnotify_put_mark(chunk_entry); /* drop initial reference */ fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ return 0;} static void audit_tree_log_remove_rule(struct audit_krule *rule){ struct audit_buffer *ab; Lines 1–500 of 1034. 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// SPDX-License-Identifier: GPL-2.0 #include "audit.h" #include <linux/fsnotify_backend.h> #include <linux/namei.h> #include <linux/mount.h> #include <linux/kthread.h> #include <linux/refcount.h> #include <linux/slab.h> struct audit_tree; struct audit_chunk; struct audit_tree { refcount_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); static struct task_struct *prune_thread; /* * 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) { refcount_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) { refcount_inc(&tree->count); } static inline void put_tree(struct audit_tree *tree) { if (refcount_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_group); chunk->mark.mask = FS_IN_IGNORED; return chunk; } enum {HASH_SIZE = 128}; static struct list_head chunk_hash_heads[HASH_SIZE]; static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock); /* Function to return search key in our hash from inode. */ static unsigned long inode_to_key(const struct inode *inode) { /* Use address pointed to by connector->obj as the key */ return (unsigned long)&inode->i_fsnotify_marks; } /* * Function to return search key in our hash from chunk. Key 0 is special and * should never be present in the hash. */ static unsigned long chunk_to_key(struct audit_chunk *chunk) { /* * We have a reference to the mark so it should be attached to a * connector. */ if (WARN_ON_ONCE(!chunk->mark.connector)) return 0; return (unsigned long)chunk->mark.connector->obj; } static inline struct list_head *chunk_hash(unsigned long key) { unsigned long n = key / 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) { unsigned long key = chunk_to_key(chunk); struct list_head *list; if (!(chunk->mark.flags & FSNOTIFY_MARK_FLAG_ATTACHED)) return; list = chunk_hash(key); list_add_rcu(&chunk->hash, list); } /* called under rcu_read_lock */ struct audit_chunk *audit_tree_lookup(const struct inode *inode) { unsigned long key = inode_to_key(inode); struct list_head *list = chunk_hash(key); struct audit_chunk *p; list_for_each_entry_rcu(p, list, hash) { if (chunk_to_key(p) == key) { atomic_long_inc(&p->refs); return p; } } return NULL; } bool 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 true; return false; } /* 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); mutex_lock(&entry->group->mark_mutex); spin_lock(&entry->lock); /* * mark_mutex protects mark from getting detached and thus also from * mark->connector->obj getting NULL. */ if (chunk->dead || !(entry->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) { spin_unlock(&entry->lock); mutex_unlock(&entry->group->mark_mutex); if (new) fsnotify_put_mark(&new->mark); 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); mutex_unlock(&entry->group->mark_mutex); fsnotify_destroy_mark(entry, audit_tree_group); goto out; } if (!new) goto Fallback; if (fsnotify_add_mark_locked(&new->mark, entry->connector->obj, FSNOTIFY_OBJ_TYPE_INODE, 1)) { fsnotify_put_mark(&new->mark); 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); mutex_unlock(&entry->group->mark_mutex); fsnotify_destroy_mark(entry, audit_tree_group); fsnotify_put_mark(&new->mark); /* drop initial reference */ 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); mutex_unlock(&entry->group->mark_mutex); 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_inode_mark(entry, inode, 0)) { fsnotify_put_mark(entry); 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, audit_tree_group); 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); fsnotify_put_mark(entry); /* drop initial reference */ 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_mark(&inode->i_fsnotify_marks, audit_tree_group); 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; mutex_lock(&old_entry->group->mark_mutex); spin_lock(&old_entry->lock); /* * mark_mutex protects mark from getting detached and thus also from * mark->connector->obj getting NULL. */ if (!(old_entry->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) { /* old_entry is being shot, lets just lie */ spin_unlock(&old_entry->lock); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_put_mark(old_entry); fsnotify_put_mark(&chunk->mark); return -ENOENT; } if (fsnotify_add_mark_locked(chunk_entry, old_entry->connector->obj, FSNOTIFY_OBJ_TYPE_INODE, 1)) { spin_unlock(&old_entry->lock); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_put_mark(chunk_entry); 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); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_destroy_mark(chunk_entry, audit_tree_group); 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); mutex_unlock(&old_entry->group->mark_mutex); fsnotify_destroy_mark(old_entry, audit_tree_group); fsnotify_put_mark(chunk_entry); /* drop initial reference */ fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ return 0; } static void audit_tree_log_remove_rule(struct audit_krule *rule) { struct audit_buffer *ab;