From: ebiederman@lnxi.com (Eric W. Biederman)
To: "David S. Miller" <davem@redhat.com>
Cc: Linus Torvalds <torvalds@transmeta.com>,
<linux-kernel@vger.kernel.org>,
Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH] Longstanding elf fix (2.4.3 fix)
Date: 23 Apr 2001 01:44:57 -0600 [thread overview]
Message-ID: <m3snj0giva.fsf@DLT.linuxnetworx.com> (raw)
In-Reply-To: <m31yqk8oas.fsf@DLT.linuxnetworx.com> <15075.40500.408470.152332@pizda.ninka.net>
In-Reply-To: "David S. Miller"'s message of "Sun, 22 Apr 2001 20:15:00 -0700 (PDT)"
"David S. Miller" <davem@redhat.com> writes:
> Eric W. Biederman writes:
> > In building a patch for 2.4.3 I also discovered that we are not taking
> > the mmap_sem around do_brk in the exec paths.
>
> Does that really matter?
In the library loader I can certainly see it making a difference.
> Who else can get at the address space?
> We are a singly referenced address space at that point... perhaps ptrace?
In practice I don't see it being a big deal. But reliable code is
made by closing all of the little loop holes.
It also improves consistency as all of the calls to do_mmap are
already protected in the exec paths.
And of course since much of the code in the kernel is built on the
copy a good example neglecting the locking without a big comment,
invites trouble elsewhere like in elf_load_library. Where we could
have multiple threads running.
Eric
next prev parent reply other threads:[~2001-04-23 7:45 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-04-23 0:14 [PATCH] Longstanding elf fix (2.4.3 fix) Eric W. Biederman
2001-04-23 3:15 ` David S. Miller
2001-04-23 7:44 ` Eric W. Biederman [this message]
2001-04-23 7:59 ` Philip Blundell
2001-04-23 16:05 ` Eric W. Biederman
2001-04-23 17:39 ` Linus Torvalds
2001-04-23 18:54 ` Eric W. Biederman
2001-04-24 22:34 ` Ion Badulescu
2001-04-24 23:34 ` Eric W. Biederman
-- strict thread matches above, loose matches on Subject: below --
2001-04-23 21:54 Manfred Spraul
2001-04-24 7:19 ` Eric W. Biederman
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=m3snj0giva.fsf@DLT.linuxnetworx.com \
--to=ebiederman@lnxi.com \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=davem@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@transmeta.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.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.