Re: bin/54069

[christos%zoulas.com@localhost (Christos Zoulas)]

The following reply was made to PR bin/54069; it has been noted by GNATS.

From: christos%zoulas.com@localhost (Christos Zoulas)
To: Ingo Schwarze <schwarze%usta.de@localhost>, gnats-bugs%NetBSD.org@localhost
Cc: Thomas Klausner <wiz%NetBSD.org@localhost>, Jason Thorpe <horpej%me.com@localhost>
Subject: Re: bin/54069
Date: Fri, 29 Mar 2019 17:59:32 -0400

 On Mar 29, 10:46pm, schwarze%usta.de@localhost (Ingo Schwarze) wrote:
 -- Subject: Re: bin/54069
 
 | Hi,
 | 
 | thanks to Jason for finding and reporting the bug, to Thomas for
 | making me aware of the PR, and to Christos for his commit, which
 | helped me understanding the bug.
 | 
 | I just fixed it upstream:
 | 
 |   http://mandoc.bsd.lv/cgi-bin/cvsweb/out.c#rev1.78
 | 
 | Note that my patch is smaller than Christos' and at a different
 | place.  It is easier to understand because that is where maxcol is
 | originally calculated.  Changing it later when it has already been
 | used for various purposes is somewhat confusing.   Maybe you want
 | to merge the upstream patch, to ease future updates and to avoid
 | ultimately ending up with a double fix.
 | 
 | Thanks,
 |   Ingo
 | 
 | 
 | Log Message:
 | -----------
 | Set the maximum column index in a tbl(7) to the maximum *right* edge 
 | of any cell span, not to the maximum *left* edge, which may be smaller 
 | if the last column of the table is only reached by horizontal spans,
 | but not by any regular cell in any row of the table.
 | Otherwise, the algorithm calculating column widths accessed memomy
 | after the end of the colwidth[] array, while it was trying to handle 
 | the rightmost column(s).
 | 
 | Crash reported by Jason Thorpe <thorpej at NetBSD>
 | via https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=54069
 | and via Thomas Klausner (wiz@).
 | Christos@ Zoulas sent a (correct, but slightly confusing) patch.
 | The patch i'm committing here is easier to understand.
 
 Thank you! I've committed your change.
 
 christos