From:   Natalia Petrova <n.petrova@fintech.ru>
To:     Ilya Dryomov <idryomov@gmail.com>
CC:     Natalia Petrova <n.petrova@fintech.ru>,
        Dongsheng Yang <dongsheng.yang@easystack.cn>,
        Jens Axboe <axboe@kernel.dk>, <ceph-devel@vger.kernel.org>,
        <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <lvc-project@linuxtesting.org>,
        "Alexey Khoroshilov" <khoroshilov@ispras.ru>
Subject: [PATCH] rbd: avoid double free memory on error path in rbd_dev_create()
Date:   Fri, 3 Feb 2023 17:15:15 +0300
Message-ID: <20230203141515.125205-1-n.petrova@fintech.ru>
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Precedence: bulk

If rbd_dev_create() fails after assignment 'opts' to 'rbd_dev->opts',
double free of 'rbd_options' happens:
one is in rbd_dev_free() and another one is in do_rbd_add().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 1643dfa4c2c8 ("rbd: introduce a per-device ordered workqueue")
Signed-off-by: Natalia Petrova <n.petrova@fintech.ru>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
---
 drivers/block/rbd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 04453f4a319c..ab6bfc352cde 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -5357,7 +5357,6 @@ static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
 	if (!rbd_dev)
 		return NULL;
 
-	rbd_dev->opts = opts;
 
 	/* get an id and fill in device name */
 	rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0,
@@ -5372,6 +5371,7 @@ static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
 	if (!rbd_dev->task_wq)
 		goto fail_dev_id;
 
+	rbd_dev->opts = opts;
 	/* we have a ref from do_rbd_add() */
 	__module_get(THIS_MODULE);
 
-- 
2.34.1