From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#24751: 26.0.50; Regex stack overflow not detected properly (gets "Variable binding depth exceeds max-specpdl-size") Date: Fri, 04 Nov 2016 10:22:08 +0200 Message-ID: <83h97nlknj.fsf@gnu.org> References: <87twc6tl0i.fsf@users.sourceforge.net> Reply-To: Eli Zaretskii NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1478247770 8433 195.159.176.226 (4 Nov 2016 08:22:50 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 4 Nov 2016 08:22:50 +0000 (UTC) Cc: 24751@debbugs.gnu.org To: npostavs@users.sourceforge.net Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Fri Nov 04 09:22:46 2016 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c2ZlK-0005j7-Bi for geb-bug-gnu-emacs@m.gmane.org; Fri, 04 Nov 2016 09:22:10 +0100 Original-Received: from localhost ([::1]:37041 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c2ZlN-00018h-75 for geb-bug-gnu-emacs@m.gmane.org; Fri, 04 Nov 2016 04:22:13 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:52744) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c2ZlH-00018R-3N for bug-gnu-emacs@gnu.org; Fri, 04 Nov 2016 04:22:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c2ZlC-0001D7-B7 for bug-gnu-emacs@gnu.org; Fri, 04 Nov 2016 04:22:07 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:55819) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1c2ZlC-0001Cx-7I for bug-gnu-emacs@gnu.org; Fri, 04 Nov 2016 04:22:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1c2ZlC-0000N6-2F for bug-gnu-emacs@gnu.org; Fri, 04 Nov 2016 04:22:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 04 Nov 2016 08:22:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 24751 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 24751-submit@debbugs.gnu.org id=B24751.14782477151413 (code B ref 24751); Fri, 04 Nov 2016 08:22:02 +0000 Original-Received: (at 24751) by debbugs.gnu.org; 4 Nov 2016 08:21:55 +0000 Original-Received: from localhost ([127.0.0.1]:42985 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c2Zl4-0000Mj-Rq for submit@debbugs.gnu.org; Fri, 04 Nov 2016 04:21:55 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:33482) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c2Zl4-0000MY-5Z for 24751@debbugs.gnu.org; Fri, 04 Nov 2016 04:21:54 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c2Zkw-0000se-04 for 24751@debbugs.gnu.org; Fri, 04 Nov 2016 04:21:49 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:46995) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c2Zkv-0000sW-TJ; Fri, 04 Nov 2016 04:21:45 -0400 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:2057 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1c2Zkv-0004pm-0K; Fri, 04 Nov 2016 04:21:45 -0400 In-reply-to: <87twc6tl0i.fsf@users.sourceforge.net> (npostavs@users.sourceforge.net) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:125325 Archived-At: > From: npostavs@users.sourceforge.net > Date: Thu, 20 Oct 2016 23:54:05 -0400 > > So we we might want to fix the re_max_failures setting in main, but it > doesn't quite make sense to me that GROW_FAIL_STACK relies on > re_max_failures being a multiple of (sizeof (fail_stack_elt_t)). At the > definition of TYPICAL_FAILURE_SIZE we have > > /* Estimate the size of data pushed by a typical failure stack entry. > An estimate is all we need, because all we use this for > is to choose a limit for how big to make the failure stack. */ > /* BEWARE, the value `20' is hard-coded in emacs.c:main(). */ > #define TYPICAL_FAILURE_SIZE 20 > > Why do we use an "estimate" here? What's wrong with just using > (re_max_failures * sizeof (fail_stack_elt_t)) as the limit? Or should > the limit actually be (re_max_failures * TYPICAL_FAILURE_SIZE * sizeof > (fail_stack_elt_t))? I think it should be the latter, indeed. Can you propose a patch along those lines that would remove the infloop in ENSURE_FAIL_STACK? Thanks.