Please sign in to comment.
Limit maximum line length in interactive shells
Dear all, it seems as if I sent around the wrong version of the patch. Please find the correct version attached to this e-mail. Kind regards, > one of our testers found out that he could reliably reboot our > erlang-based device by just sending tons of 'A' characters to an > interactive shell. > > It appears that the I/O server of the interactive shell (in group.erl) > is always reading a full line before doing any end-of-input processing, > so that by sending bytes without a newline in between, it slowly eats up > all available memory. > > The patch attached to this e-mail fixes that by introducing a new > io:setopt() option in group.erl named 'max_length' that is used to check > whether the current line length exceeds this maximum whenever the line > is edited. If an overlong line is detected, max_length bytes are > returned immediately (without the actual stop condition being fulfilled, > though, allowing I/O clients to detect this situation). > > max_length is allowed to be an integer() > 0 or 'unlimited'. The default > is 'unlimited' to have the old behaviour by default. > > > > Kind regards, > > _______________________________________________ > erlang-patches mailing list > firstname.lastname@example.org > http://erlang.org/mailman/listinfo/erlang-patches -- Dr. Stefan Zegenhagen arcutronix GmbH Garbsener Landstr. 10 30419 Hannover Germany Tel: +49 511 277-2734 Fax: +49 511 277-2709 Email: email@example.com Web: www.arcutronix.com *Synchronize the Ethernet* General Managers: Dipl. Ing. Juergen Schroeder, Dr. Josef Gfrerer - Legal Form: GmbH, Registered office: Hannover, HRB 202442, Amtsgericht Hannover; Ust-Id: DE257551767. Please consider the environment before printing this message. >From b8b904f4ca1e0b418f8e758c9aa5e43b6469c3b4 Mon Sep 17 00:00:00 2001 From: Stefan Zegenhagen <firstname.lastname@example.org> Date: Tue, 7 May 2013 14:14:50 +0200 Subject: [PATCH] limit line length in interactive shells Since the I/O server in group.erl was always collecting full lines before doing any further end-of-input processing, it was possible to crash any erlang system by just sending tons of characters without any newline to an interactive shell. Fix that by allowing to specify a maximum input length. Whenever new characters are received from the input device, check whether the new input exceeds the maximum line length and if so, return the data that was read so far (up to the maximum line length characters).
- Loading branch information...
Showing with 101 additions and 13 deletions.