Re: [PATCH] lib/string: Introduce sysfs_streqcase

[Gioh Kim]

On Fri, Apr 2, 2021 at 8:24 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
> On Fri, Apr 02, 2021 at 11:17:13AM -0700, Nick Desaulniers wrote:
> > Thanks for the patch!
> >
> > + akpm (please remember to run ./scripts/get_maintainer.pl on your patch files)
> >
> > On Fri, Apr 2, 2021 at 2:41 AM Gioh Kim <gi-oh.kim@xxxxxxxxx> wrote:
> > >
> > > As the name shows, it checks if strings are equal in case insensitive
> > > manner. I found some cases using strncasecmp to check the entire
> > > strings and they would not work as intended.
> > >
> > > For example, drivers/infiniband/ulp/rtrs/rtrs-clt-sysfs.c uses
> > > strncasecmp to check that the input via sysfs is "mi". But it would
> > > work even-if the input is "min-wrongcommand".
> > > And also drivers/pnp/interface.c checks "disable" command with
> > > strncasecmp but it would also work if the command is "disable-wrong".
> >
> > Perhaps those callers should be using strcasecmp then, rather than strncasecmp?
> >
> > Also, if they're being liberal in accepting either case, I don't see
> > why the sysfs nodes should be strict in rejecting trailing input at
> > that point.
>
> I think this shouldn't be prefixed "sysfs_" -- name it for what it does,
> not where it gets used, if it's a general utility function.
>

I think sysfs_streqcase is another version of sysfs_streq.
That is why I use "sysfs_" prefix.