Re: [PATCH] dax: replace sprintf() by scnprintf()

From: Salah Triki
Date: Mon Jul 12 2021 - 08:26:45 EST


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