Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
Message-ID: <7b796b3e-2fd9-00bc-5410-1097512162be@suse.de>
Date:   Fri, 8 Apr 2022 01:18:20 +0800
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0)
 Gecko/20100101 Thunderbird/91.7.0
Subject: Re: [PATCH v2] md: bcache: check the return value of kzalloc() in
 detached_dev_do_request()
Content-Language: en-US
To:     Jia-Ju Bai <baijiaju1990@gmail.com>
Cc:     linux-bcache@vger.kernel.org, kent.overstreet@gmail.com,
        linux-kernel@vger.kernel.org
References: <20220303015544.32186-1-baijiaju1990@gmail.com>
From:   Coly Li <colyli@suse.de>
In-Reply-To: <20220303015544.32186-1-baijiaju1990@gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 3/3/22 9:55 AM, Jia-Ju Bai wrote:
> The function kzalloc() in detached_dev_do_request() can fail, so its
> return value should be checked.
>
> Fixes: bc082a55d25c ("bcache: fix inaccurate io state for detached bcache devices")
> Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
> ---
> v2:
> * Fix the error handling code when ddip is NULL.
>    Thank Coly for good advice.
>
> ---
>   drivers/md/bcache/request.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> index d15aae6c51c1..673a680240a9 100644
> --- a/drivers/md/bcache/request.c
> +++ b/drivers/md/bcache/request.c
> @@ -1107,6 +1107,12 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
>   	 * which would call closure_get(&dc->disk.cl)
>   	 */
>   	ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
> +	if (!ddip) {
> +		bio->bi_status = BLK_STS_RESOURCE;
> +		bio->bi_end_io(bio);
> +		return;
> +	}
> +
>   	ddip->d = d;
>   	/* Count on the bcache device */
>   	ddip->orig_bdev = orig_bdev;

Added into my testing queue.

Thanks.


Coly Li