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From:   Ye Bin <yebin10@huawei.com>
To:     <jack@suse.com>, <linux-kernel@vger.kernel.org>
CC:     <yebin10@huawei.com>, Jan Kara <jack@suse.cz>,
        <syzbot+e633c79ceaecbf479854@syzkaller.appspotmail.com>
Subject: [PATCH v2 1/2] quota: Properly disable quotas when add_dquot_ref() fails
Date:   Mon, 5 Jun 2023 22:07:30 +0800
Message-ID: <20230605140731.2427629-2-yebin10@huawei.com>
In-Reply-To: <20230605140731.2427629-1-yebin10@huawei.com>
References: <20230605140731.2427629-1-yebin10@huawei.com>
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From: Jan Kara <jack@suse.cz>

When add_dquot_ref() fails (usually due to IO error or ENOMEM), we want
to disable quotas we are trying to enable. However dquot_disable() call
was passed just the flags we are enabling so in case flags ==
DQUOT_USAGE_ENABLED dquot_disable() call will just fail with EINVAL
instead of properly disabling quotas. Fix the problem by always passing
DQUOT_LIMITS_ENABLED | DQUOT_USAGE_ENABLED to dquot_disable() in this
case.

Reported-and-tested-by: Ye Bin <yebin10@huawei.com>
Reported-by: syzbot+e633c79ceaecbf479854@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/quota/dquot.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index ffd40dc3e4e9..6beceed34e08 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -2420,7 +2420,8 @@ int dquot_load_quota_sb(struct super_block *sb, int type, int format_id,
 
 	error = add_dquot_ref(sb, type);
 	if (error)
-		dquot_disable(sb, type, flags);
+		dquot_disable(sb, type,
+			      DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 
 	return error;
 out_fmt:
-- 
2.31.1