audit: Provide helper for dropping mark's chunk reference

Provide a helper function audit_mark_put_chunk() for dropping mark's
reference (which has to happen only after RCU grace period expires).
Currently that happens only from a single place but in later patches we
introduce more callers.

Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
Jan Kara 2018-11-12 09:54:49 -05:00 committed by Paul Moore
parent 8cd0feb523
commit a8375713fb
1 changed files with 11 additions and 1 deletions

View File

@ -132,10 +132,20 @@ static void __put_chunk(struct rcu_head *rcu)
audit_put_chunk(chunk);
}
/*
* Drop reference to the chunk that was held by the mark. This is the reference
* that gets dropped after we've removed the chunk from the hash table and we
* use it to make sure chunk cannot be freed before RCU grace period expires.
*/
static void audit_mark_put_chunk(struct audit_chunk *chunk)
{
call_rcu(&chunk->head, __put_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);
audit_mark_put_chunk(chunk);
}
static struct audit_chunk *alloc_chunk(int count)