Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > gnu.bash.bug > #14652

Re: bash sockets: printf \x0a does TCP fragmentation

Path csiph.com!xmission!news.snarked.org!news.linkpendium.com!news.linkpendium.com!panix!usenet.stanford.edu!not-for-mail
From Greg Wooledge <wooledg@eeg.ccf.org>
Newsgroups gnu.bash.bug
Subject Re: bash sockets: printf \x0a does TCP fragmentation
Date Mon, 24 Sep 2018 09:05:33 -0400
Lines 22
Approved bug-bash@gnu.org
Message-ID <mailman.1224.1537794758.1284.bug-bash@gnu.org> (permalink)
References <c6de6616-dda0-570d-de56-419e7676be8a@cbii-hh.de> <20180921231101307758654@bob.proulx.com> <714e1ba0-0052-2f2b-676d-778f2b7129c1@testssl.sh>
NNTP-Posting-Host lists.gnu.org
Mime-Version 1.0
Content-Type text/plain; charset=us-ascii
X-Trace usenet.stanford.edu 1537794758 24661 208.118.235.17 (24 Sep 2018 13:12:38 GMT)
X-Complaints-To action@cs.stanford.edu
To bug-bash@gnu.org
Envelope-to bug-bash@gnu.org
Mail-Followup-To bug-bash@gnu.org
Content-Disposition inline
In-Reply-To <714e1ba0-0052-2f2b-676d-778f2b7129c1@testssl.sh>
User-Agent NeoMutt/20170113 (1.7.2)
X-detected-operating-system by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic]
X-Received-From 139.137.100.1
X-BeenThere bug-bash@gnu.org
X-Mailman-Version 2.1.21
Precedence list
List-Id Bug reports for the GNU Bourne Again SHell <bug-bash.gnu.org>
List-Unsubscribe <https://lists.gnu.org/mailman/options/bug-bash>, <mailto:bug-bash-request@gnu.org?subject=unsubscribe>
List-Archive <http://lists.gnu.org/archive/html/bug-bash/>
List-Post <mailto:bug-bash@gnu.org>
List-Help <mailto:bug-bash-request@gnu.org?subject=help>
List-Subscribe <https://lists.gnu.org/mailman/listinfo/bug-bash>, <mailto:bug-bash-request@gnu.org?subject=subscribe>
Xref csiph.com gnu.bash.bug:14652

Show key headers only | View raw


On Sat, Sep 22, 2018 at 11:50:17AM +0200, dirk+bash@testssl.sh wrote:
> On 9/22/18 7:30 AM, Bob Proulx wrote:
> > dirk+bash@testssl.sh wrote:
> >> printf -- "$data" >&5 2>/dev/null
> > 
> > What happens if $data contains % format strings?  What happens if the
> > format contains a sequence such as \c?  This looks problematic.  This
> > is not a safe programming proctice.

Looking ONLY at this one line, there is an obvious bug, which Bob has
pointed out.  It should be

printf %s "$data" >&5 2>/dev/null

> I doubt you can judge on this by just looking at a single line
> of code -- the project has > 18k LoC in bash.

That is utterly horrifying.

I have no comments on the buffering issues.  Those have already been
covered.

Back to gnu.bash.bug | Previous | Next | Find similar | Unroll thread


Thread

Re: bash sockets: printf \x0a does TCP fragmentation Greg Wooledge <wooledg@eeg.ccf.org> - 2018-09-24 09:05 -0400

csiph-web