mbcache: make sure c_entry_count is not decremented past zero

Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
CC: Eric Biggers <ebiggers@google.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Jan Kara <jack@suse.cz>
This commit is contained in:
Jiang Biao 2018-01-09 23:57:52 -05:00 committed by Theodore Ts'o
parent a90ac0f5dc
commit 9ee93ba3c4
1 changed files with 3 additions and 1 deletions

View File

@ -239,6 +239,8 @@ void mb_cache_entry_delete(struct mb_cache *cache, u32 key, u64 value)
spin_lock(&cache->c_list_lock);
if (!list_empty(&entry->e_list)) {
list_del_init(&entry->e_list);
if (!WARN_ONCE(cache->c_entry_count == 0,
"mbcache: attempt to decrement c_entry_count past zero"))
cache->c_entry_count--;
atomic_dec(&entry->e_refcnt);
}