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Message-ID: <10621e048f62018432c42a3fccc1a5fd9a6d71d7.camel@perches.com>
Subject: Re: [PATCH] dax: replace sprintf() by scnprintf()
From:   Joe Perches <joe@perches.com>
To:     Salah Triki <salah.triki@gmail.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
Date:   Sat, 10 Jul 2021 10:04:48 -0700
In-Reply-To: <20210710164615.GA690067@pc>
References: <20210710164615.GA690067@pc>
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On Sat, 2021-07-10 at 17:46 +0100, Salah Triki wrote:
> Replace sprintf() by scnprintf() in order to avoid buffer overflows.

OK but also not strictly necessary.  DAX_NAME_LEN is 30.

Are you finding and changing these manually or with a script?

> diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
[]
> @@ -76,7 +76,7 @@ static ssize_t do_id_store(struct device_driver *drv, const char *buf,
> ?	fields = sscanf(buf, "dax%d.%d", &region_id, &id);
> ?	if (fields != 2)
> ?		return -EINVAL;
> -	sprintf(devname, "dax%d.%d", region_id, id);
> +	scnprintf(devname, DAX_NAME_LEN, "dax%d.%d", region_id, id);
> ?	if (!sysfs_streq(buf, devname))
> ?		return -EINVAL;
> ?
>