From: David Gibson <hermes@gibson.dropbear.id.au>
To: "Randy.Dunlap" <rddunlap@osdl.org>
Cc: netdev@oss.sgi.com, jgarzik@pobox.com
Subject: Re: [PATRCH] janitor: hermes: delete verify_area call
Date: Tue, 30 Sep 2003 14:51:10 +1000 [thread overview]
Message-ID: <20030930045110.GG15200@zax> (raw)
In-Reply-To: <20030929130608.156bbc2b.rddunlap@osdl.org>
On Mon, Sep 29, 2003 at 01:06:08PM -0700, Randy.Dunlap wrote:
> On Mon, 29 Sep 2003 15:29:25 +1000 David Gibson <hermes@gibson.dropbear.id.au> wrote:
>
> | On Thu, Sep 25, 2003 at 09:59:02PM -0700, Randy.Dunlap wrote:
> | >
> | > Hi,
> | > Please apply to 2.6.0-test5-current.
> | >
> | > Thanks,
> |
> | Sorry, can you clarify why this verify_area() is not needed?
>
>
> Sure, I'll try to do that.
> There are several related reasons for it.
>
> Summary:
> Using verify_area() [or access_ok()] is redundant if copy*user(),
> get_user(), or put_user() is being used, but must (*should*) be used
> if __copy*user(), __get_user(), or __put_user() are being used.
>
> a. [include/asm-i386/uaccess.h] verify_area: - Obsolete, use access_ok()
>
> b. copy_*_user() already calls access_ok() to validate the user address.
> The __* versions of copy*user() and __get/put_user() do not use
> access_ok(), so checking must be done before using them.
Ah, ok, thanks. In that case presumably the other call to
verify_area() doesn't need to be there either...
--
David Gibson | For every complex problem there is a
david@gibson.dropbear.id.au | solution which is simple, neat and
| wrong.
http://www.ozlabs.org/people/dgibson
next prev parent reply other threads:[~2003-09-30 4:51 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-09-26 4:59 [PATRCH] janitor: hermes: delete verify_area call Randy.Dunlap
2003-09-29 5:29 ` David Gibson
2003-09-29 20:06 ` Randy.Dunlap
2003-09-30 4:51 ` David Gibson [this message]
2003-09-30 5:15 ` David S. Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20030930045110.GG15200@zax \
--to=hermes@gibson.dropbear.id.au \
--cc=jgarzik@pobox.com \
--cc=netdev@oss.sgi.com \
--cc=rddunlap@osdl.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).