Debian bug report logs - #1088 ncurses - segfault in wnoutrefresh in dpkg 0.93.53 Package: ncurses-developer ; Reported by: iwj10@cus.cam.ac.uk (Ian Jackson); 113 days old . ----------------------------------------------------------------------- Message received at debian-bugs: From pixar.com!bruce Sat Jul 22 20:49:16 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sZs2W-0005QmC; Sat, 22 Jul 95 20:49 PDT Received: from mongo.pixar.com by pixar.com with SMTP id AA22392 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Sat, 22 Jul 1995 20:47:42 -0700 Received: by mongo.pixar.com (Smail3.1.28.1 #15) id m0sZryz-0005QmC; Sat, 22 Jul 95 20:45 PDT Message-Id: To: iwj10@cus.cam.ac.uk (Ian Jackson), debian-bugs@Pixar.com Cc: bruce@Pixar.com Subject: Re: Bug#1088: ncurses - segfault in wnoutrefresh In-Reply-To: Your message of "Sun, 23 Jul 1995 00:21:00 PDT." Date: Sat, 22 Jul 1995 20:45:37 -0700 From: Bruce Perens Yes, I did see the rectangle in the upper left rendered before everything else, and I also saw some lines cleared and than rendered with one space in the left before being redrawn with their proper contents. I put that up to strange movement optimization, but I'll take it up with them. Rather than have them look at the whole of dpkg, can you put the relevant fragments (refreshing windows, etc.) in a mail message along with questions? You'll be more likely to get a response that way. Thanks Bruce ----------------------------------------------------------------------- Acknowledgement sent to Bruce Perens : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1088 ; Package ncurses-developer . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From cus.cam.ac.uk!iwj10 Sat Jul 22 16:50:00 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sZoIy-0004BqC; Sat, 22 Jul 95 16:50 PDT Received: from bootes.cus.cam.ac.uk by pixar.com with SMTP id AA09425 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Sat, 22 Jul 1995 16:48:16 -0700 Received: by bootes.cus.cam.ac.uk (Smail-3.1.29.0 #36) id m0sZoIi-000BzOC; Sun, 23 Jul 95 00:49 BST Received: by chiark id (Debian /\oo/\ Smail3.1.29.1 #29.32); Sun, 23 Jul 95 00:21 BST Message-Id: Date: Sun, 23 Jul 95 00:21 BST From: iwj10@cus.cam.ac.uk (Ian Jackson) To: debian-bugs@Pixar.com Subject: Re: Bug#1088: ncurses - segfault in wnoutrefresh In-Reply-To: References: Bruce Perens writes ("Re: Bug#1088: ncurses - segfault in wnoutrefresh "): > iwj10@cus.cam.ac.uk said: > > However it's still doing something very weird that I think is > > probably a bug somewere. > > On my ANSI terminal emulation at work, it looked OK, though some of the > decisions it made about movement optimization were strange. Sorry, I've not made myself clear. You'll notice that it redraws a rectangle near the top left of the package list before everything else. I find this highly suspicious. There is nothing in my code that makes that rectangle special; the whole package list is a single pad which is pnoutrefresh'd all at once. The displayed data doesn't make it special either. I think that this bizarre redraw order is another symptom of the same bug that caused the coredump with 1.9.2c. It seems likely to me that it is coincidence that with 1.9.3 the numbers that are the corners of the rectangle are sane enough for it to redraw that part apparently correctly, and that in 1.9.2c it just happened to be sufficiently badly off to cause a coredump. I won't be convinced that this rectangle isn't an abberation involving some kind of incorrectly calculated quantities until someone shows me how it was derived :-). > I'll look at it on > my Linux at home as soon as I can to see if it's a linux-terminfo problem. If > it's solely a matter of not liking the movement optimization, I think we > should wait before complaining about that, as they've just worked over the > movement optimization for the next release. No, I don't think it is just a problem with the movement optimization. What I'd really like is for one of the ncurses team to look over my code and see what it ought to do and compare it with what it does. If you point them to me I can explain the window/pad structures I'm using, or answer their questions. > What were you running it under? Xterm? The linux console? What was $TERM > set to? Did it behave the same way under both xterm and the console? TERM=xterm in an 80x24 xterm (3.1.1-1 at the time, but it does it with 3.1.1-2 too). In fact, I've just tried it (0.93.62 dselect, List, Redraw) in an 80x37 xterm (3.1.1-2) and I get a segfault. If I try making my xterm bigger one line at a time I find that the earlier-drawn rectangle shrinks, and that I get a segfault when it has shrunk to nothing. I can't reproduce the problem with a 132x43 Linux console with TERM=console or TERM=linux. TERM=con132x43 (the default for my 1.2.10 kernel) produces a string of messages about errors in terminal entries and then appears to hang. Ian. ----------------------------------------------------------------------- Acknowledgement sent to iwj10@cus.cam.ac.uk (Ian Jackson) : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1088 ; Package ncurses-developer . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From pixar.com!bruce Fri Jul 21 17:27:16 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sZSPT-0003DbC; Fri, 21 Jul 95 17:27 PDT Received: from mongo.pixar.com by pixar.com with SMTP id AA24124 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Fri, 21 Jul 1995 17:25:41 -0700 Received: by mongo.pixar.com (Smail3.1.28.1 #15) id m0sZSOO-0003GFC; Fri, 21 Jul 95 17:26 PDT Message-Id: X-Mailer: exmh version 1.6.2 7/18/95 To: iwj10@cus.cam.ac.uk (Ian Jackson), debian-bugs@Pixar.com Cc: bruce@Pixar.com Subject: Re: Bug#1088: ncurses - segfault in wnoutrefresh In-Reply-To: Your message of "Fri, 21 Jul 1995 22:11:00 PDT." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 21 Jul 1995 17:26:08 -0700 From: Bruce Perens iwj10@cus.cam.ac.uk said: > However it's still doing something very weird that I think is > probably a bug somewere. On my ANSI terminal emulation at work, it looked OK, though some of the decisions it made about movement optimization were strange. I'll look at it on my Linux at home as soon as I can to see if it's a linux-terminfo problem. If it's solely a matter of not liking the movement optimization, I think we should wait before complaining about that, as they've just worked over the movement optimization for the next release. What were you running it under? Xterm? The linux console? What was $TERM set to? Did it behave the same way under both xterm and the console? If I'm seeing what you are complaining about, I'm perhaps not recognizing it. Can I have a few more words about what "something very weird" is? Thanks Bruce -- -- Attention Ham Radio Operators: For information on "Linux for Hams", read -- the World Wide Web page http://www.hams.com/perens/LinuxForHams, or send -- an e-mail message containing the word "help" to info@hams.com . ----------------------------------------------------------------------- Acknowledgement sent to Bruce Perens : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1088 ; Package ncurses-developer . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From cus.cam.ac.uk!iwj10 Fri Jul 21 16:11:26 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sZRE6-000B84C; Fri, 21 Jul 95 16:11 PDT Received: from bootes.cus.cam.ac.uk by pixar.com with SMTP id AA15844 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Fri, 21 Jul 1995 16:08:12 -0700 Received: by bootes.cus.cam.ac.uk (Smail-3.1.29.0 #36) id m0sZQ2k-000C0jC; Fri, 21 Jul 95 22:55 BST Received: by chiark id (Debian /\oo/\ Smail3.1.29.1 #29.32); Fri, 21 Jul 95 22:11 BST Message-Id: Date: Fri, 21 Jul 95 22:11 BST From: iwj10@cus.cam.ac.uk (Ian Jackson) To: debian-bugs@pixar.com Subject: Re: Bug#1088: ncurses - segfault in wnoutrefresh In-Reply-To: References: Bruce Perens writes: > Ian, is this still happening with ncurses-1.9.3 ? No, it's not. However it's still doing something very weird that I think is probably a bug somewhere. Here is a typescript which demonstrates the effect. For best results use something like slowprint 0.001 ); $|=1; $overhead= 0.0125; $delay= @ARGV ? $ARGV[0]+0 : 0.025; $per=1; while ($delay < $overhead) { $per*=2; $delay*=2; } $delay -= $overhead; while (length($v)) { print substr($v,0,$per); $v=substr($v,$per); select("","","",$delay); } begin 664 typescript.gz M'XL(``,7$#`"`^U:6T_;2!1^K[2_("_G#8H@8),K:+OBUJ8%45I@M2M$RV!/ MXEE\B69L0E[ZV_<EVFZ]J9W\X0>UW+Q!,7FU\6_TGBZ_>P+?5-!#Q M0*WZ_%*P>-4?7@U6UNK=]7K+7?45#[F7VCO\EH.$M3>U-@X:[:!VUJN=N1]J M9TZTFZ^'=X>GJPY"'1P3JO,=:P--`J$%Q2+22XC+BPF$GQN/KU&I)9&6D>DT_.8EAB1]%C; M#EVJDGXZ8I(V;^LE#5RR03.P)?A(?GW68[O=K0#]228*.WRBL7$\/N:LT7-X M=W(?.-$I>O'+$6`@P)?#9?`RJ1#^BH_)TK%(!0LAY&G*)7Y!&XN!2'-#:LQ- M!*&0.9)<*=@[/-G[3),>64!&YB$2$67Y=09/R) M6U$HF9BODSF'8RD&00J+.Z\I=QK+E$#P'L/[`YI1Y19P*!1.`J$`__H(7IAN M$\70L8K)`.]XS"5J=91=AL*#`^'QV.-P;;9U$8E"`75%XW*9F]M#"2A/4"U? MD#H*Q3H).+H%-SO\"+B-9'$Z)CG:QL0=<^_JNVM,[SKF[IK[NKDW]'U]L[-& M>=?=19.];.(U;S-ZYH29`HX,[X#F#T,>)M7-QF!2S*2-"7P3N7%*"@!& M^1D*INZ(B.4E0I9L;!_OKAR(E!NV+87Q@OZMU:8T];!DH8G[F(QH"1%C$@V9%$@CD-G-='B6@V!5+D"LXR.T$U91 M1G2BS9Z3Q]U"K$.^%)J[?364R4!95^S]=>*BQF$!6@AI";T4-_OAYD-D2V@@ZH0Z&*8,H8P*+DS%])XG`,S/.P&-9? MWR&KHY#GDN:5\B)8P$HXY$@J/BZA>AHD(X@2+"D!#X=4?;TP\VD/2F/3$1F^ MH_J3,#2LF9*J MM.FM-KJ<7XA[0F(AS66<3#UVF60I;6G8-\!:'5*]QO`S]EI4U&)-IM=L4%RUCC#;6/$2YB8\@]P&]81,&= M$R`1]P234_Q,%0&*H]RW(QXB%="&EL6??>4\3NB=GB7V?:+@]98>-8M1RTZV M[:!C!UT[,$F^7V3I?I%1^T4R[!>QNV\"3H\*7*<`=@IDM\!S"SRW0-'`!O7N M?E,/]^;E-G]XN?RORF1'!_E,5#WQ@FF)`C):HN%T MSN1M6>ELJW*V73G;J9SM5L[JG\#ETXY^QT/37Q^8=JM7VYR?,J[Y.<_]3;A] MP;0X8FJC^$@_]8DC[K4T97N]D/L>(+M'U]E2=B*Y#SL@.8F2K+2'A6ELR3R8),*535Q7Z_5P2/I.:* M%":%".19_8PS[V?^]_U,!!'O^813S=N7G.^UE2/KQ)[X>XX!V<;AM?BQL?BSLY8Z%M2:/A;ULR$[\ M/ZTZ4)Y!1K_ZL;!?4W1=8-JX=M-MR%I'5X(_&NV0Q@\=.WYUK`\N^PG6K?NG 0EML;CCFU_"_A3+SNX2P``-JX ` end ----------------------------------------------------------------------- Acknowledgement sent to iwj10@cus.cam.ac.uk (Ian Jackson) : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1088 ; Package ncurses-developer . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From pixar.com!bruce Tue Jul 18 21:28:45 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sYQkX-000604C; Tue, 18 Jul 95 21:28 PDT Received: from mongo.pixar.com by pixar.com with SMTP id AA22152 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Tue, 18 Jul 1995 21:27:12 -0700 Received: by mongo.pixar.com (Smail3.1.28.1 #15) id m0sYQhm-000604C; Tue, 18 Jul 95 21:25 PDT Message-Id: Date: Tue, 18 Jul 95 21:25 PDT From: bruce@pixar.com (Bruce Perens) To: debian-bugs@pixar.com, iwj10@cus.cam.ac.uk Subject: Re: Bug#1088: Acknowledgement (was: ncurses - segfault in wnoutrefresh Ian, is this still happening with ncurses-1.9.3 ? Thanks Bruce -- -- Attention Ham Radio Operators: For information on "Linux for Hams", read -- the World Wide Web page http://www.hams.com/perens/LinuxForHams, or send -- an e-mail message containing the word "help" to info@hams.com . ----------------------------------------------------------------------- Acknowledgement sent to bruce@pixar.com (Bruce Perens) : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1088 ; Package ncurses-developer . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From cus.cam.ac.uk!iwj10 Mon Jul 10 06:44:16 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sVJ8C-0005nTC; Mon, 10 Jul 95 06:44 PDT Received: from bootes.cus.cam.ac.uk by pixar.com with SMTP id AA21370 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Mon, 10 Jul 1995 06:42:43 -0700 Received: by bootes.cus.cam.ac.uk (Smail-3.1.29.0 #36) id m0sVJ86-000C00C; Mon, 10 Jul 95 14:44 BST Received: by chiark id (Debian /\oo/\ Smail3.1.29.1 #29.32); Mon, 10 Jul 95 00:32 BST Message-Id: Date: Mon, 10 Jul 95 00:32 BST From: iwj10@cus.cam.ac.uk (Ian Jackson) To: Debian bugs submission address Subject: ncurses - segfault in wnoutrefresh in dpkg 0.93.53 Package: ncurses-developer Version: 1.9.2c-1 To reproduce: * start dselect 0.93.53; * enter the package list (option 2); * hit ^L to redraw the display. The result is a coredump in wnoutrefresh. The arguments appear to be sane. I haven't investigated whether this is an overwriting (memory corruption) problem in dselect because the last time I had an overwriting problem it turned out to be ncurses infecting the rest of the program rather than the other way around. The bug happens with 0.93.42.3 too, and probably with other versions. If you want to debug this and have Electric Fence installed the easiest way is probably to use the `debugmake' script in the dpkg 0.93.53 source tarfile's `lib' and `dselect' directories. dpkg-0.93.53.tar.gz is currently in private/project/ALPHA; when I upload dpkg 0.93.54 I'll move it to dpkg-0.93.53-ncursesbug.tar.gz. Ian. ----------------------------------------------------------------------- Acknowledgement sent to iwj10@cus.cam.ac.uk (Ian Jackson) : New bug report received and forwarded. Full text available. ----------------------------------------------------------------------- Report forwarded to debian-devel@pixar.com : Bug#1088 ; Package ncurses-developer . Full text available. ----------------------------------------------------------------------- Ian Jackson / iwj10@thor.cam.ac.uk , with the debian-bugs tracking mechanism This page last modified 07:43:01 GMT Wed 01 Nov