#554711 lynx-cur: Signal 11 on certain pages in UTF-8 locales

Package:
lynx-cur
Source:
lynx
Submitter:
"Deekoo L."
Date:
2023-04-26 10:03:09 UTC
Severity:
normal
Tags:
#554711#5
Date:
2009-11-06 07:18:49 UTC
From:
To:
Lynx crashed with a bus error when I attempted to use it to poke at an URL
from a spam I'd gotten.  Upgrading to 2.8.8dev.1-1 fixed the crash on the
unmodified page, but a slightly modified version of the spammer's page still
crashes with a signal 11.

Since it's a spammer's page, it's highly possible that it'll try to install
malware of some sort when visited, (and also possible that the Lynx crash is
a failed exploit - or a successful exploit that's managed to hide everything
but the crash from me), and the copy on my site has only been changed enough
to make it crash the latest Lynx in testing; I have NOT done anything that
would remove a malicious payload from it.  That being said,
LANG=en_US.UTF-8 lynx http://deekoo.net/peeves/spam/signal11.html
will crash; LANG=C lynx http://deekoo.net/peeves/spam/signal11.html will
not crash.

The previous version of Lynx from testing that I was using (I don't,
unfortunately, remember the version I was using) would crash in an assortment
of different ways (bus error, signal 11, dump message) depending on how I
changed the offending page; it wouldn't crash if I removed the ar-sa or
windows-1256 meta tags from the page.

(And my email address should be deliverable - hopefully its length will break
address extractors, though.)
#554711#10
Date:
2009-11-22 21:09:27 UTC
From:
To:
I can't reproduce this (did the page change?).
#554711#15
Date:
2009-11-22 21:09:27 UTC
From:
To:
I can't reproduce this (did the page change?).
#554711#20
Date:
2009-11-26 17:39:11 UTC
From:
To:
I haven't changed it, and it still crashes for me (tested in xterm, Eterm,
and console.).

I poked around a bit more, and it turns out that installing lynx-cur-wrapper
masks the crash; removing lynx-cur-wrapper brings it back.
#554711#25
Date:
2009-11-26 19:29:26 UTC
From:
To:
I made a copy of it, just in case, when I looked at it, this weekend.
(I see the url says today that it was last modified November 6).

lynx-cur-wrapper mainly is used to supply extra lynx.cfg flavors that set
the PREFERRED_LANGUAGE value.  For en_US.UTF-8 it should not have
to do anything.  However, it also does use the values of $TERM and
$COLORTERM -- if _adding_ lynx-cur-wrapper caused a problem, I'd
look there.

I should be able to duplicate your setting without removing
lynx-cur-wrapper by just typing

 	LYNX_CFG=/etc/lynx-cur/lynx.cfg /usr/bin/lynx.cur signal11.html

...but it's not breaking for me, still.

Outside of lynx, my ncurses libraries are newer - from last weekend rather
than August 3.

You might be able to get a core dump (and using gdb, a minimal walkback),
to give an idea where the problem lies, using lynx's -core option.