LU-17678 quota: fix memleak in qmt_setup_lqe_gd()

a race in qmt_setup_lqe_gd() can lead to leaked lqe_glbl_data.

Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Change-Id: I807aa276fa373cec493cae9d8182b28d996f5a8b
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/54575
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Sergey Cheremencev <scherementsev@ddn.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>

diff --git a/lustre/quota/qmt_entry.c b/lustre/quota/qmt_entry.c
index 6c37036..5a55034 100644 (file)
--- a/lustre/quota/qmt_entry.c
+++ b/lustre/quota/qmt_entry.c
@@ -1323,7 +1323,15 @@ void qmt_setup_lqe_gd(const struct lu_env *env, struct qmt_device *qmt,
                                  lqe_qtype(lqe), &lqe->lqe_id);
        qmt_seed_glbe(env, lgd, false);
 
-       lqe->lqe_glbl_data = lgd;
+       mutex_lock(&lqe->lqe_glbl_data_lock);
+       if (lqe->lqe_glbl_data == NULL) {
+               lqe->lqe_glbl_data = lgd;
+               lgd = NULL;
+       }
+       mutex_unlock(&lqe->lqe_glbl_data_lock);
+       if (lgd)
+               qmt_free_lqe_gd(lgd);
+
        qmt_id_lock_notify(qmt, lqe);
 
        qti_lqes_fini(env);