From: Christoph Hellwig <hch@infradead.org>
To: Rich Felker <dalias@aerifal.cx>
Cc: David Drysdale <drysdale@google.com>,
Andy Lutomirski <luto@amacapital.net>,
libc-alpha <libc-alpha@sourceware.org>,
musl@lists.openwall.com,
Andrew Morton <akpm@linux-foundation.org>,
Linux API <linux-api@vger.kernel.org>,
Christoph Hellwig <hch@infradead.org>
Subject: Re: [musl] Re: [RFC] Possible new execveat(2) Linux syscall
Date: Fri, 21 Nov 2014 02:10:15 -0800 [thread overview]
Message-ID: <20141121101015.GF8866@infradead.org> (raw)
In-Reply-To: <20141117183010.GE22465@brightrain.aerifal.cx>
On Mon, Nov 17, 2014 at 01:30:10PM -0500, Rich Felker wrote:
> On Mon, Nov 17, 2014 at 03:42:15PM +0000, David Drysdale wrote:
> > I'm not familiar with O_EXEC either, I'm afraid, so to be clear -- does
> > O_EXEC mean the permission check is explicitly skipped later, at execute
> > time? In other words, if you open(O_EXEC) an executable then remove the
> > execute bit from the file, does a subsequent fexecve() still work?
>
> Yes. It's just like how read and write permissions work. If you open a
> file for read then remove read permissions, or open it for write then
> remove write permissions, the existing permissions to the open file
> are not lost. Of course open with O_EXEC/O_SEARCH needs to fail if the
> caller does not have +x access to the file/directory at the time of
> open.
Adding a FMODE_EXEC similar to FMODE_READ/WRITE would be trivial.
next prev parent reply other threads:[~2014-11-21 10:10 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAHse=S8ccC2No5EYS0Pex=Ng3oXjfDB9woOBmMY_k+EgxtODZA@mail.gmail.com>
2014-11-16 19:52 ` Rich Felker
[not found] ` <20141116195246.GX22465-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org>
2014-11-16 21:20 ` Andy Lutomirski
2014-11-16 22:08 ` Rich Felker
[not found] ` <20141116220859.GY22465-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org>
2014-11-16 22:34 ` Andy Lutomirski
2014-11-16 23:32 ` [musl] " Rich Felker
[not found] ` <20141116233202.GA22465-C3MtFaGISjmo6RMmaWD+6Sb1p8zYI1N1@public.gmane.org>
2014-11-17 0:06 ` Andy Lutomirski
2014-11-17 15:42 ` David Drysdale
2014-11-17 18:30 ` Rich Felker
2014-11-21 10:10 ` Christoph Hellwig [this message]
2014-11-21 10:13 ` Christoph Hellwig
[not found] ` <20141121101318.GG8866-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2014-11-21 13:49 ` David Drysdale
[not found] ` <CAHse=S9RATqvXSrFXxDOcWx7Ub94Yhyr_-=USib-PPMx+_CC-w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-11-21 14:15 ` [musl] " Rich Felker
2014-11-21 14:11 ` Rich Felker
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=20141121101015.GF8866@infradead.org \
--to=hch@infradead.org \
--cc=akpm@linux-foundation.org \
--cc=dalias@aerifal.cx \
--cc=drysdale@google.com \
--cc=libc-alpha@sourceware.org \
--cc=linux-api@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=musl@lists.openwall.com \
/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.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/musl/
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).