From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Nate Karstens <nate.karstens@garmin.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Jeff Layton <jlayton@kernel.org>,
"J. Bruce Fields" <bfields@fieldses.org>,
Arnd Bergmann <arnd@arndb.de>,
Richard Henderson <rth@twiddle.net>,
Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
Matt Turner <mattst88@gmail.com>, Helge Deller <deller@gmx.de>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org,
linux-alpha@vger.kernel.org, linux-parisc@vger.kernel.org,
sparclinux@vger.kernel.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Cc: Changli Gao <xiaosuo@gmail.com>
Subject: Re: Implement close-on-fork
Date: Wed, 22 Apr 2020 07:32:55 -0700 [thread overview]
Message-ID: <1587565975.3485.5.camel@HansenPartnership.com> (raw)
In-Reply-To: <20200420071548.62112-1-nate.karstens@garmin.com>
On Mon, 2020-04-20 at 02:15 -0500, Nate Karstens wrote:
> Series of 4 patches to implement close-on-fork. Tests have been
> published to https://github.com/nkarstens/ltp/tree/close-on-fork.
>
> close-on-fork addresses race conditions in system(), which
> (depending on the implementation) is non-atomic in that it
> first calls a fork() and then an exec().
Why is this a problem? I get that there's a time between fork and exec
when you have open file descriptors, but they should still be running
in the binary context of the programme that called fork, i.e. under
your control. The security problems don't seem to occur until you exec
some random binary, which close on exec covers. So what problem would
close on fork fix?
> This functionality was approved by the Austin Common Standards
> Revision Group for inclusion in the next revision of the POSIX
> standard (see issue 1318 in the Austin Group Defect Tracker).
URL? Does this standard give a reason why the functionality might be
useful.
James
next prev parent reply other threads:[~2020-04-22 14:33 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-20 7:15 Implement close-on-fork Nate Karstens
2020-04-20 7:15 ` [PATCH 1/4] fs: " Nate Karstens
2020-04-20 10:25 ` Eric Dumazet
2020-04-22 3:38 ` Changli Gao
2020-04-22 3:41 ` Changli Gao
2020-04-22 8:35 ` David Laight
2020-05-01 14:45 ` Karstens, Nate
2020-05-01 15:23 ` Matthew Wilcox
2020-05-03 13:52 ` David Laight
2020-04-22 15:36 ` Karstens, Nate
2020-04-22 15:43 ` Matthew Wilcox
2020-04-22 16:02 ` Karstens, Nate
2020-04-22 16:31 ` Bernd Petrovitsch
2020-04-22 16:55 ` David Laight
2020-04-23 12:34 ` Bernd Petrovitsch
2020-04-20 7:15 ` [PATCH 2/4] fs: Add O_CLOFORK flag for open(2) and dup3(2) Nate Karstens
2020-04-20 7:15 ` [PATCH 3/4] fs: Add F_DUPFD_CLOFORK to fcntl(2) Nate Karstens
2020-04-20 7:15 ` [PATCH 4/4] net: Add SOCK_CLOFORK Nate Karstens
2020-04-22 14:32 ` James Bottomley [this message]
2020-04-22 15:01 ` Implement close-on-fork Al Viro
2020-04-22 15:18 ` Matthew Wilcox
2020-04-22 15:34 ` James Bottomley
2020-04-22 16:00 ` Al Viro
2020-04-22 16:13 ` Al Viro
2020-05-04 13:46 ` Karstens, Nate
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=1587565975.3485.5.camel@HansenPartnership.com \
--to=james.bottomley@hansenpartnership.com \
--cc=arnd@arndb.de \
--cc=bfields@fieldses.org \
--cc=davem@davemloft.net \
--cc=deller@gmx.de \
--cc=ink@jurassic.park.msu.ru \
--cc=jlayton@kernel.org \
--cc=kuba@kernel.org \
--cc=linux-alpha@vger.kernel.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-parisc@vger.kernel.org \
--cc=mattst88@gmail.com \
--cc=nate.karstens@garmin.com \
--cc=netdev@vger.kernel.org \
--cc=rth@twiddle.net \
--cc=sparclinux@vger.kernel.org \
--cc=viro@zeniv.linux.org.uk \
--cc=xiaosuo@gmail.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 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).