Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c22fcde7 authored by Jan Kara's avatar Jan Kara Committed by Paul Moore
Browse files

audit: Drop all unused chunk nodes during deletion 



When deleting chunk from a tree, drop all unused nodes in a chunk
instead of just the one used by the tree. This gets rid of possibly
lingering unused nodes (created due to fallback path in untag_chunk())
and also removes some special cases and will allow us to simplify
locking in untag_chunk().

Signed-off-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent 49a4ee7d

kernel/audit_tree.c

+18 −9
Original line number Diff line number Diff line
@@ -277,8 +277,7 @@ static struct audit_chunk *find_chunk(struct node *p) 
	return container_of(p, struct audit_chunk, owners[0]);

}



static void replace_chunk(struct audit_chunk *new, struct audit_chunk *old,

			  struct node *skip)

static void replace_chunk(struct audit_chunk *new, struct audit_chunk *old)

{

	struct audit_tree *owner;

	int i, j;
@@ -288,7 +287,7 @@ static void replace_chunk(struct audit_chunk *new, struct audit_chunk *old, 
	list_for_each_entry(owner, &new->trees, same_root)

		owner->root = new;

	for (i = j = 0; j < old->count; i++, j++) {

		if (&old->owners[j] == skip) {

		if (!old->owners[j].owner) {

			i--;

			continue;

		}
@@ -322,20 +321,28 @@ static void remove_chunk_node(struct audit_chunk *chunk, struct node *p) 
	put_tree(owner);

}



static int chunk_count_trees(struct audit_chunk *chunk)

{

	int i;

	int ret = 0;



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

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

			ret++;

	return ret;

}



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;

	int size = chunk->count - 1;

	int size;



	remove_chunk_node(chunk, p);

	fsnotify_get_mark(entry);

	spin_unlock(&hash_lock);



	if (size)

		new = alloc_chunk(size);



	mutex_lock(&entry->group->mark_mutex);

	/*

	 * mark_mutex protects mark from getting detached and thus also from
@@ -348,6 +355,7 @@ static void untag_chunk(struct node *p) 
		goto out;

	}



	size = chunk_count_trees(chunk);

	if (!size) {

		chunk->dead = 1;

		spin_lock(&hash_lock);
@@ -360,6 +368,7 @@ static void untag_chunk(struct node *p) 
		goto out;

	}



	new = alloc_chunk(size);

	if (!new)

		goto out_mutex;
@@ -375,7 +384,7 @@ static void untag_chunk(struct node *p) 
	 * This has to go last when updating chunk as once replace_chunk() is

	 * called, new RCU readers can see the new chunk.

	 */

	replace_chunk(new, chunk, p);

	replace_chunk(new, chunk);

	spin_unlock(&hash_lock);

	fsnotify_detach_mark(entry);

	mutex_unlock(&entry->group->mark_mutex);
@@ -520,7 +529,7 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) 
	 * This has to go last when updating chunk as once replace_chunk() is

	 * called, new RCU readers can see the new chunk.

	 */

	replace_chunk(chunk, old, NULL);

	replace_chunk(chunk, old);

	spin_unlock(&hash_lock);

	fsnotify_detach_mark(old_entry);

	mutex_unlock(&audit_tree_group->mark_mutex);