[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 24 Jul 2019 18:17:40 +0000
From: "Gote, Nitin R" <nitin.r.gote@...el.com>
To: Joe Perches <joe@...ches.com>, Kees Cook <keescook@...omium.org>
CC: "corbet@....net" <corbet@....net>, "akpm@...ux-foundation.org"
<akpm@...ux-foundation.org>, "apw@...onical.com" <apw@...onical.com>,
"linux-doc@...r.kernel.org" <linux-doc@...r.kernel.org>,
"kernel-hardening@...ts.openwall.com" <kernel-hardening@...ts.openwall.com>
Subject: RE: [PATCH v5] Documentation/checkpatch: Prefer strscpy/strscpy_pad
over strcpy/strlcpy/strncpy
Hi,
> -----Original Message-----
> From: Gote, Nitin R [mailto:nitin.r.gote@...el.com]
> Sent: Tuesday, July 23, 2019 2:56 PM
> To: Joe Perches <joe@...ches.com>; Kees Cook <keescook@...omium.org>
> Cc: corbet@....net; akpm@...ux-foundation.org; apw@...onical.com;
> linux-doc@...r.kernel.org; kernel-hardening@...ts.openwall.com
> Subject: RE: [PATCH v5] Documentation/checkpatch: Prefer
> strscpy/strscpy_pad over strcpy/strlcpy/strncpy
>
>
> > -----Original Message-----
> > From: Joe Perches [mailto:joe@...ches.com]
> > Sent: Monday, July 22, 2019 11:11 PM
> > To: Kees Cook <keescook@...omium.org>; Gote, Nitin R
> > <nitin.r.gote@...el.com>
> > Cc: corbet@....net; akpm@...ux-foundation.org; apw@...onical.com;
> > linux-doc@...r.kernel.org; kernel-hardening@...ts.openwall.com
> > Subject: Re: [PATCH v5] Documentation/checkpatch: Prefer
> > strscpy/strscpy_pad over strcpy/strlcpy/strncpy
> >
> > On Mon, 2019-07-22 at 10:30 -0700, Kees Cook wrote:
> > > On Wed, Jul 17, 2019 at 10:00:05AM +0530, NitinGote wrote:
> > > > From: Nitin Gote <nitin.r.gote@...el.com>
> > > >
> > > > Added check in checkpatch.pl to
> > > > 1. Deprecate strcpy() in favor of strscpy().
> > > > 2. Deprecate strlcpy() in favor of strscpy().
> > > > 3. Deprecate strncpy() in favor of strscpy() or strscpy_pad().
> > > >
> > > > Updated strncpy() section in Documentation/process/deprecated.rst
> > > > to cover strscpy_pad() case.
> > > >
> > > > Signed-off-by: Nitin Gote <nitin.r.gote@...el.com>
> > >
> > > Reviewed-by: Kees Cook <keescook@...omium.org>
> > >
> > > Joe, does this address your checkpatch concerns?
> >
> > Well, kinda.
> >
> > strscpy_pad isn't used anywhere in the kernel.
> >
> > And
> >
> > + "strncpy" => "strscpy, strscpy_pad or
> for non-
> > NUL-terminated strings, strncpy() can still be used, but destinations
> > should be marked with __nonstring",
> >
> > is a bit verbose. This could be simply:
> >
> > + "strncpy" => "strscpy - for non-NUL-terminated uses,
> > + strncpy() dst
> > should be __nonstring",
> >
>
Could you please give your opinion on below comment.
> But, if the destination buffer needs extra NUL-padding for remaining size of
> destination, then safe replacement is strscpy_pad(). Right? If yes, then what
> is your opinion on below change :
>
> "strncpy" => "strscpy, strcpy_pad - for non-NUL-terminated uses,
> strncpy() dst should be __nonstring",
>
>
If you agree on this, then I will include this change in next patch version.
> -Nitin
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
