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Date:   Mon, 12 Jul 2021 13:26:24 +0100
From:   Salah Triki <salah.triki@gmail.com>
To:     Joe Perches <joe@perches.com>
Cc:     dan.j.williams@intel.com, vishal.l.verma@intel.com,
        dave.jiang@intel.com, nvdimm@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] dax: replace sprintf() by scnprintf()
Message-ID: <20210712122624.GB777994@pc>
References: <20210710164615.GA690067@pc>
 <10621e048f62018432c42a3fccc1a5fd9a6d71d7.camel@perches.com>
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On Sat, Jul 10, 2021 at 10:04:48AM -0700, Joe Perches wrote:
> 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;
> > ?
> > 
> 
> 

since region_id and id are unsigned long may be devname should be
char[21].

I'm finding and changing these manually.

Thanx