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Anatomy Of A Bug In Microsoft Office
bender writes "An insightful look at what it is like to track down and fix a bug in Microsoft Office is available from Microsoft's Blog site."
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I can already fix MS Office bugs by myself!
1. Does it affect Clippy? Fix immediately!
2. Does it affect features? Fix this week.
3. Does it affect security? Fix when you get around to it.
what it is like to track down and fix a bug
:)
Track a bug? Sounds like trying to follow a single mosquito in the ranforest.
Step 1: Deny existence of bug.
Step 2: Classify bug as feature.
Step 3: Cave to user demand and try to fix bug.
Step 4: Introduce new bugs during the fix.
Step 5: Classify those bugs as features.
Step 6: Pretend bugs are fixed and continue playing Minesweeper.
Here, drive this Yugo instead.
Cretin - a powerful and flexible CD reencoder
One of my favorite Chris Mason quotes comes from that memo, "Since human beings themselves are not fully debugged yet, there will be bugs in your code no matter what you do."
Then it would seem humans working at Microsoft are less debugged than everybody else. Because *boy*, at some point Microsoft was a bug factory.
To their credit though, this is changing fast. Microsoft is a huge company that can turn on a dime, and they've understood that having shite engineers onboard won't do much good to their latest "trustworthy computing" PR stunt. Not to mention, they actually have a nice R&D shop now, not just the pretense of one anymore.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Humans are bugs, err, humans are viruses. Correction: Humans have bugs.
Programs are like onions. Ogres are like onions. Donkeys like cake.
Mac Office X is the red-headed step child of Microsoft development efforts
Microsoft is a lot like the police.
--
Was it the sheep climbing onto the altar, or the cattle lowing to be slain,
or the Son of God hanging dead and bloodied on a cross that told me this was a world condemned, but loved and bought with blood.
Why don't they fix that awful formatting in MS Word?
You know, push enter twice and it returns to the default font/size. That really bothers me.
Click here for a free picture of an iPod!
"And, always remember that I can't fix what I can't see. I have to be able to reproduce the problem while being able to run some kind of diagnostic tool. The key to fixing a bug is predictability. Without predictability, I can't fix it, because without predictability I have no way to understand how the complex interactions in modern software cause the specific problem to occur."
I wonder if they'll do another writeup when they fix the next bug.
___
It's the end of my comment as I know it and I feel fine.
I figured out the missing step: Marketing!
Do you want it buggy today or robust tomorrow? One need only look at the overclocking community and throngs of beta-testers to work out the answer. History is littered with technically superior failures in the marketplace (Betamax, Divx, BeOS) and the reason is that the consumer is more fickle about price and features than about technical superiority or stability.
Read any book put out by Microsoft Press and it's plain there are a number of people there that are as or more capable than most open source programmers. But the open source programmer doesn't have to appease any person or schedule other than those he sets himself -- and can therefore program under much better circumstances.
Try not. Do or do not, there is no try.
-- Dr. Spock, stardate 2822-3.
From the article
But there is a benefit to discussing complexity because it does seem to impact how many bugs arise and the maintainability, upgradeability, and usability of the software.
It's not merely a philosophical issue, either. This is a real, practical issue that impacts millions of people everyday.
The complexity of interacting software components is like the dark side of Metcalfe's Law about the usefulness of networks increasing quadratically with the number of participants in the network.
The maintainability of software decreases as the number of interacting components increase and as the number of ways of interaction increases.
I've developed code for a long time and seen great ideas turn into great code with creeping useful features gradually added on until a day comes when you wonder how you ended up working on such a monstrosity.
A good friend once told me years ago
"Provided by the management for your protection."
Cut the sarcasm. It really is innovative. It makes chunks of the document independent of what file they're in, and paved the way for an efficient implementation of our beloved "multiple undo" feature. And bear in mind that this was over 20 years ago, when the desktop software industry was just getting started and there was little prior experience to draw on.
Karma: Segmentation fault (tried to dereference a null post)
Have you read about all the new bugs that are being found in SP2.
Yes, and most of what is written is junk.
There are compaints about how the SP2 security panel can be spoofed.
Yes, they are uninformed compliants.
This allows a person to trick people into thinking their firewall and virus scan are all on and working normally.
Any person?
Microsoft's response... (paraphrased quote) "We are busy with other more important bugs at the time, don't bother us with these tivialities."
Umm.. no, thats a blantant distortion.
Here is the story you don't want to know:
A program running locally on the XP SP2 machine has the ability to overwrite the data store used to track and display the various updated components in XP SP2.
This isn't a remote vulnerability. It means that, simply put, a program can constantly overwrite the data that would indicate a virus scan hasn't taken place in 15 days, or that the firewall is off or open on certain ports, etc.
To have this "vulernability" be "exploited", first the protection would have to be subverted/turned off by the user. Nothing in this "exploit" allows an application to disable the features, just make them look as though they are in place. So after a program infilitrates the system and is running as an Administrator, it would be able to make the user think that the protection they already disabled was in fact running.
This is not a big deal. For example, let's say I had a program I could find a way to get onto a box with root access. I could just easily, if not more easily, spoof the security center interface and make it say what ever I wanted. I could just as easily spoof it to say "OH NO, GO DOWNLOAD THIS PATCH".
The point being this is a hole in the design or implementation. It's a social engineering attack. To be useful, the user would have to disable the protection on the machine; the user would then have to be convinced to download the trojan; the user would have to be induced to run the trojan; and the user would have to believe that he/she was in fact protected despite knowingly disabling the protection.
The nature of any operating system is that it responds to users actions. If any person/program can convince any user on any operating system to run any malicious binary as root/Administrator/etc than that box is exploitable by means of social engineering. Big deal. That's not new, it's not a security vulnerability per se, it's not anything but human nature.
Well, it's not *that* simple.
Figuring out how to best represent a document in memory can be more complicated than it would seem. Say, the easiest way would be just to malloc a chunk of memory for the whole document, but try to insert text into the middle of a 100 page document if you do it that way.
A more workable approach is to make it be an array with one entry per line, but that can run into exactly the same problem if you write a long enough paragraph.
So perhaps you go with something even more abstract, say, some kind of structure that contains pointers to words, which allows you to insert several invisible blanks every time you need to make space for stuff to reduce the time spent on memory management.
I think the article meant something similar to that last one.
gl4ss is completely correct.
Win95 was THE MOST ADVANCED OS in the world!
Win98 fixed all the bugs in Win95.
Win98SE fixed all the bugs in Win98.
Windows2000 is crash proof and the Unix killer!
Windows XP is even more stable than Win2K and will be sure to slay *nix.
Go digging through the press releases and gushing "journalists" for every single release (except WinME) since (and including) Win95. You'll see the same quotes over and over and over.
Several bugs have been sighted near the southern perimeter and some of our QA staff have been wounded in a couple of minor skirmishes. Strategic Command said the enemy's main move will not come for weeks and certainly not in this sector, though I am beginning to doubt.
27-08-2004 08:26The skirmishes have intensified and several QA squads are trapped between an unknown number of bugs. We even had a few lightning strikes beyond our perimeter, which took out our BugTraq listening post. I tried to call in for assistence from StratCom, because I suspect the main strike is happening here as we speak. 27-08-2004 08:54
The minor skirmishes have ceased along all sectors. We are trying to evacuate the wounded and salvage what's left of some of our equipment. 3rd QA batallion took heavy losses, as did 6th QA and 8th Helpdesk. What is this, some cat and mouse game they are playing with us?
27-08-2004 09:06All hell broke loose! While we were trying to evacuate the wounded, we found our sector under attack from multiple vectors, including artillery and naval support. Whatever remained of 3rd and 6th QA that was stationed in the rear has now been wiped out. 8th Helpdesk has been decimated and I had no other option to commit 24th, 12th and 2nd Developer batallion to the battle, at least untill reinforcements arrive. The enemy seems to be using a superior number of SFU-506 "Sasser" class fighters with ActiveX payloads. I nearly begged StratCom to send some "KB900364" SAM batteries.
27-08-2004 15:56We have pulled back and regrouped in Sector 56. 3rd, 4th, 6th QA got decimated. 8th, 12th and 15th Helpdesk have been routed as well. 24th, 12th and 2nd Developer have been utterly destroyed to save the rest from annihilation. The few who remain are now en-route back home. Some are shell-shocked, one fat guy keeps jumping around yelling "Developers!"... Poor sod, this is war at it's worst.
Gee, I wonder why.
--Rob
Towards the Singularity.
Describes a huge chunk of my life in Software QA. It's an example of what is great about MS software and what is awful:
Great: dedicated test resources to chase down corner cases/non-obvious scenarios, accountability for broken scenarios, etc
Awful: Iterations of releases built on legacy code means no one (or two, or three) people can understand the problem or scope the fix.
For all the complaints here about MS code I wonder that no one has noticed the Windows weakness that is not getting exploited..? If MS software is really as bad as everyone here makes out then why doesn't someone do it better? Blah blah Linux blah blah... Build software for Windows that people can use without rebuilding their systems. If you do it well enough tell them it's even better on Platform X.
Insert predictable rant here about how there are no bugs in Free software because any user could fix the bug themselves...
I agree. No doubt there will be a few who suggest the many-eyes approach will fix all the world's evils... it won't, it will let a developer who can be bothered to sift through the thousands/millions of lines of code necessary to fix the bug - this is a dedicated programmer and deserves credit for that... the world is not full of a large number of dedicated intelligent programmers who have time to do this for all, or even a small fraction of code they encounter - if you use Open SOurce (I use BSD/Windows with open/prop apps, don't bother with the 'jokes') do really look through every line of code looking for a buffer overflow exploit, do you pro-rata what you look through with the assumed userbase, do you assume others will do the QC/QA/peer review? Sure it could be made to be ultra-secure, and for this I am all in favour of Open Source (there is absolutely no security through obscurity, as those that need to know will know), but I really have a gripe with those that blindly use the many-eyes assumption and group-think, auto-mod others who disagree. If you want to criticise MS Office, then do something about it.
MS Office is massive, MS Office may be bloated to those who does not use all those features (and who does?!), but the idea of modulising Office suites, good or bad idea that may be, died miserabley in the last 90s.
MS Office is inferior, functionality and UI wise, to specialist applications made for a certain job - I would never do serious statistical analysis in Excel nor would i distribute a Word doc, nor would I make a webpage in Word(!).
Criticise it for valid reason, not knee-jerk group think, but it does serve as a good lowest-common-denominator suite that integrates OK for an intermediate solution. Open software may also suck at many tasks, but carries the benefit it is open. If I see the 'many eyes' justification for all opensource software refered to again, without proper justification I think I will throw my computer out of the window - please mods - don't just mod something down because you disagree with it, if you disagree contribute and bring effective discussion rather than pushing an opinion out of the room - save downmods for things which are clearly Offtopic, Flamebait or Trollish (and baiting discussion is not Flamebait, it is Discussion-Bait).
Haha. You even got +5, Insightful. Why don't we look at the rest of the sentence?
Brodie figured out that a document is really just a collection of pieces of text, and that it didn't really matter where each piece of text is physically located within the document's file.
I.e., if you're going to have "The dog is red." appears in the document, it doesn't matter if "The" occurs in the file before "red", or vice-versa.
Maybe this seems trivial to you, but I think most of us when designing a document format would try to put "The" before "dog", by instinct. It makes sense.
So what he figured out is not as straightforward as your out-of-context quotation makes it out to be. He was, at least, being a little creative. The article then goes onto explain multiple ways in which this design was useful in Word processing software.
I realize you're just being an asshole and that you probably didn't read the article, but just looked for a way to use it to make fun of Microsoft. "Standard Operating Procedure" at Slashdot, I know.
But, moderators, this guy doesn't deserve Insightful. He should be Flamebait.
They spent years in the dark that the "disk is full" error was caused by too many open files.
You'd think that if the disk isn't actually full, you'd look at other places that can generate that error. Even though obviously the error should have been along the lines of "too many open files".
Note that this underlying problem isn't just a technical one. You get over-general error messages on windows (and with various badly designed software) all the time.
The least you can do when you pop-up an error is to give some additional information; like where it occurred ("Bad Thing Happened in somefile.c line #456"), so even if, like in this case, you can't reproduce the error in a debugger, you know where the error got kicked into being. Not quite as useful as a full stacktrace like in Java, but pretty usefull.
Compare this to how (non-Microsoft) geeks write error codes; from man ep;
ep0: 3c509 in test mode. Erase pencil mark!
This means that someone has scribbled with pencil in the test area on the card. Erase the pencil mark and reboot. (This is not a joke).
Even if you don't understand the error code, at least you can google for its pretty unique description "erase pencil mark".
SCO employee? Check out the bounty
Comment removed based on user account deletion
have you ever actually released software into the wild?
I came across a bug in one of my active enterprise systems today that I had never seen before, and none of my 1500 users had reported it. It would have never been found had i not been just screwing around with random things.
Give the MS guys some credit here, they have a lot of things to go over with constantly looming deadlines. You can't test EVERYTHING.
?SYNTAX ERROR IN LINE 42
Obviously you've never tried to make big documents with Word.
Writing a book with pictures in Word is extremely difficult. It randomly moves stuff around, changes fonts, and deletes sections of the code when you exceed somewhere around 2MB file size (or 10 pages...I'm not really sure about the limit).
The interface isn't the whole problem either. Exporting to rtf format creates files that don't actually meet the rtf specification (which has been defined by Microsoft, by the way), so have errors (even when read by Microsoft's rtf importer), and html output is even worse.
Latex has more features than Word without any of these problems. Also, given the original "find a bug and win money" challenge, I think I can say it is probably one of the most stable pieces of software on the planet, and it has an extension mechanism built in (Word does too, by the way - several of them).
There are some things that Microsoft makes that beat the competition, but I don't think that Word is one of them.
Mod me down and I will become more powerful than you can possibly imagine!
You can blab and whine all you want about complexity. Then you gotta explain why, since Word 95, there's been an issue with Section Breaks spontaneously changing type, and causing page numbering problems.
Still exists in Word 2003.
Countless usenet posts exist describing the anguish of VBA programmers when they encounter this bug, classify the behavior, report it to Microsoft, find out it's been a known issue for over 9 years, with no plan to fix it.
That's not caused by complexity. That's caused by bad management. Folks with no conscience. No pride in their work.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
Once you tie Word down, hold a knife to its throat and say "No. Really. I know what I'm doing -- back off," it's really quite good.
It's not an issue of bugs, it's an issue of features turned on by default. Unfortunately (as I said above), you need to call off the dogs in about 100 different places before Word becomes really good.
Cretin - a powerful and flexible CD reencoder
...is a pretty good analogy when you thnk about it:
* MS Word/Office is built around a big, powerful and complex engine, just like a Ferrari. Both are high-performance but tempermental and quirky.
* OpenOffice is derived from another project (StarOffice) which Sun bought (through purchase of StarDivision) rather than invented itself. The Yugo is derived from the Zastava GTL from Eastern Europe, the design of which Zastava bought (from Fiat for the Fiat 128) rather than invented itself.
* The casual MS Word user is completely mystified by its exotic internal workings. When things go wrong they must contend with clueless and/or irritated tech support people who offer incomprehensible advice. Proper support is expensive. The Ferrari driver is also mystified by the internal workings of his car, and when things go wrong must contend with a clueless and/or irritated Italian mechanic who offers incomprehensible advice. Parts and labour are expensive.
* The dealer network was always sparse and is now non-existant, so Yugo drivers must fend for themselves by searching the wrecking yards for parts. The internal workings are primitive but well known to owners--there is no fancy, proprietary technology. Tech support for OpenOffice is sparse to non-existant, so OO.o users must fend for themselves by Googling for patches on the 'net. The source is less complex than that of MS Office and is open, so it is known to many of its users.
* A lot of people know and use MS office because it is more powerful and popular than the rest, so they put up with all the annoyances and pay a lot of money for it, even though they don't use it to its full potential. Most Ferrari drivers buy a Ferrari because it is powerful and a popular status symbol, so they put up with all the annoyances and pay a fortune for it, even if they can't legally drive it anywhere NEAR it's full potential--and seldom do.
* Properly cared for, a Yugo can serve you well as basic transportation--even though it has less features than a lot of other cars and is slow to start. OpenOffice, properly used, can serve you well as a productivity suite--even though it has less features than some other office suites and is a bit slow to start.
* Both the Yugo and OpenOffice can be obtained and used for basically no money and some amount of tinkering.