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Date:   Tue, 20 Sep 2022 10:38:38 -0700
From:   Dan Williams <dan.j.williams@intel.com>
To:     Bo Liu <liubo03@inspur.com>, <dan.j.williams@intel.com>,
        <vishal.l.verma@intel.com>, <dave.jiang@intel.com>
CC:     <nvdimm@lists.linux.dev>, <linux-kernel@vger.kernel.org>,
        Bo Liu <liubo03@inspur.com>
Subject: RE: [PATCH] dax: Check dev_set_name() return value
Message-ID: <6329fa9e928de_2a6ded294c@dwillia2-xfh.jf.intel.com.notmuch>
References: <20220805053319.3865-1-liubo03@inspur.com>
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Bo Liu wrote:
> It's possible that dev_set_name() returns -ENOMEM, catch and handle this.
> 
> Signed-off-by: Bo Liu <liubo03@inspur.com>
> ---
>  drivers/dax/bus.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
> index 1dad813ee4a6..36cf245ee467 100644
> --- a/drivers/dax/bus.c
> +++ b/drivers/dax/bus.c
> @@ -765,7 +765,12 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id)
>  	device_initialize(dev);
>  	dev->parent = &dev_dax->dev;
>  	dev->type = &dax_mapping_type;
> -	dev_set_name(dev, "mapping%d", mapping->id);
> +	rc = dev_set_name(dev, "mapping%d", mapping->id);
> +	if (rc) {
> +		kfree(mapping);

No, this needs to trigger put_device() otherwise it leaks mapping->id.