Re: [syzbot] [PATCH] ocfs2: fix use-after-free due to dangling quota pointer and checking suspended flag

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Subject: [PATCH] ocfs2: fix use-after-free due to dangling quota pointer and checking suspended flag
Author: dennis.lamerice@xxxxxxxxx

Signed-off-by: Dennis Lam <dennis.lamerice@xxxxxxxxx>
---
#syz test

 fs/ocfs2/quota_global.c | 3 ++-
 fs/ocfs2/quota_local.c  | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index 2b0daced98eb..c6d38340d6d4 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -893,7 +893,8 @@ static int ocfs2_get_next_id(struct super_block *sb, struct kqid *qid)
 	int status = 0;
 
 	trace_ocfs2_get_next_id(from_kqid(&init_user_ns, *qid), type);
-	if (!sb_has_quota_loaded(sb, type)) {
+	if (!sb_has_quota_loaded(sb, type) ||
+			sb_dqopt(sb)->flags & DQUOT_SUSPENDED) {
 		status = -ESRCH;
 		goto out;
 	}
diff --git a/fs/ocfs2/quota_local.c b/fs/ocfs2/quota_local.c
index 73d3367c533b..2956d888c131 100644
--- a/fs/ocfs2/quota_local.c
+++ b/fs/ocfs2/quota_local.c
@@ -867,6 +867,7 @@ static int ocfs2_local_free_info(struct super_block *sb, int type)
 	brelse(oinfo->dqi_libh);
 	brelse(oinfo->dqi_lqi_bh);
 	kfree(oinfo);
+	info->dqi_priv = NULL;
 	return status;
 }
 
-- 
2.47.0