Simson Garfinkel 11.08.05

Last month automaker Toyota announced a recall of 160,000 of its Prius hybrid vehicles following reports of vehicle warning lights illuminating for no reason, and cars’ gasoline engines stalling unexpectedly. But unlike the large-scale auto recalls of years past, the root of the Prius issue wasn’t a hardware problem — it was a programming error in the smart car’s embedded code. The Prius had a software bug.

With that recall, the Prius joined the ranks of the buggy computer — a club that began in 1945 when engineers found a moth in Panel F, Relay #70 of the Harvard Mark II system.The computer was running a test of its multiplier and adder when the engineers noticed something was wrong. The moth was trapped, removed and taped into the computer’s logbook with the words: “first actual case of a bug being found.”

Sixty years later, computer bugs are still with us, and show no sign of going extinct. As the line between software and hardware blurs, coding errors are increasingly playing tricks on our daily lives. Bugs don’t just inhabit our operating systems and applications — today they lurk within our cell phones and our pacemakers, our power plants and medical equipment. And now, in our cars.

But which are the worst?

It’s all too easy to come up with a list of bugs that have wreaked havoc. It’s harder to rate their severity. Which is worse — a security vulnerability that’s exploited by a computer worm to shut down the internet for a few days or a typo that triggers a day-long crash of the nation’s phone system? The answer depends on whether you want to make a phone call or check your e-mail.

Many people believe the worst bugs are those that cause fatalities. To be sure, there haven’t been many, but cases like the Therac-25 are widely seen as warnings against the widespread deployment of software in safety critical applications. Experts who study such systems, though, warn that even though the software might kill a few people, focusing on these fatalities risks inhibiting the migration of technology into areas where smarter processing is sorely needed. In the end, they say, the lack of software might kill more people than the inevitable bugs.

What seems certain is that bugs are here to stay. Here, in chronological order, is the Wired News list of the 10 worst software bugs of all time … so far.

July 28, 1962 — Mariner I space probe. A bug in the flight software for the Mariner 1 causes the rocket to divert from its intended path on launch. Mission control destroys the rocket over the Atlantic Ocean. The investigation into the accident discovers that a formula written on paper in pencil was improperly transcribed into computer code, causing the computer to miscalculate the rocket’s trajectory.

1982 — Soviet gas pipeline. Operatives working for the Central Intelligence Agency allegedly (.pdf) plant a bug in a Canadian computer system purchased to control the trans-Siberian gas pipeline. The Soviets had obtained the system as part of a wide-ranging effort to covertly purchase or steal sensitive U.S. technology. The CIA reportedly found out about the program and decided to make it backfire with equipment that would pass Soviet inspection and then fail once in operation. The resulting event is reportedly the largest non-nuclear explosion in the planet’s history.

1985-1987 — Therac-25 medical accelerator. A radiation therapy device malfunctions and delivers lethal radiation doses at several medical facilities. Based upon a previous design, the Therac-25 was an “improved” therapy system that could deliver two different kinds of radiation: either a low-power electron beam (beta particles) or X-rays. The Therac-25′s X-rays were generated by smashing high-power electrons into a metal target positioned between the electron gun and the patient. A second “improvement” was the replacement of the older Therac-20′s electromechanical safety interlocks with software control, a decision made because software was perceived to be more reliable.

What engineers didn’t know was that both the 20 and the 25 were built upon an operating system that had been kludged together by a programmer with no formal training. Because of a subtle bug called a “race condition,” a quick-fingered typist could accidentally configure the Therac-25 so the electron beam would fire in high-power mode but with the metal X-ray target out of position. At least five patients die; others are seriously injured.

1988 — Buffer overflow in Berkeley Unix finger daemon. The first internet worm (the so-called Morris Worm) infects between 2,000 and 6,000 computers in less than a day by taking advantage of a buffer overflow. The specific code is a function in the standard input/output library routine called gets() designed to get a line of text over the network. Unfortunately, gets() has no provision to limit its input, and an overly large input allows the worm to take over any machine to which it can connect.

Programmers respond by attempting to stamp out the gets() function in working code, but they refuse to remove it from the C programming language’s standard input/output library, where it remains to this day.

1988-1996 — Kerberos Random Number Generator. The authors of the Kerberos security system neglect to properly “seed” the program’s random number generator with a truly random seed. As a result, for eight years it is possible to trivially break into any computer that relies on Kerberos for authentication. It is unknown if this bug was ever actually exploited.

January 15, 1990 — AT&T Network Outage. A bug in a new release of the software that controls AT&T’s #4ESS long distance switches causes these mammoth computers to crash when they receive a specific message from one of their neighboring machines — a message that the neighbors send out when they recover from a crash.

One day a switch in New York crashes and reboots, causing its neighboring switches to crash, then their neighbors’ neighbors, and so on. Soon, 114 switches are crashing and rebooting every six seconds, leaving an estimated 60 thousand people without long distance service for nine hours. The fix: engineers load the previous software release.

1993 — Intel Pentium floating point divide. A silicon error causes Intel’s highly promoted Pentium chip to make mistakes when dividing floating-point numbers that occur within a specific range. For example, dividing 4195835.0/3145727.0 yields 1.33374 instead of 1.33382, an error of 0.006 percent. Although the bug affects few users, it becomes a public relations nightmare. With an estimated 3 million to 5 million defective chips in circulation, at first Intel only offers to replace Pentium chips for consumers who can prove that they need high accuracy; eventually the company relents and agrees to replace the chips for anyone who complains. The bug ultimately costs Intel $475 million.

1995/1996 — The Ping of Death. A lack of sanity checks and error handling in the IP fragmentation reassembly code makes it possible to crash a wide variety of operating systems by sending a malformed “ping” packet from anywhere on the internet. Most obviously affected are computers running Windows, which lock up and display the so-called “blue screen of death” when they receive these packets. But the attack also affects many Macintosh and Unix systems as well.

June 4, 1996 — Ariane 5 Flight 501. Working code for the Ariane 4 rocket is reused in the Ariane 5, but the Ariane 5′s faster engines trigger a bug in an arithmetic routine inside the rocket’s flight computer. The error is in the code that converts a 64-bit floating-point number to a 16-bit signed integer. The faster engines cause the 64-bit numbers to be larger in the Ariane 5 than in the Ariane 4, triggering an overflow condition that results in the flight computer crashing.

First Flight 501′s backup computer crashes, followed 0.05 seconds later by a crash of the primary computer. As a result of these crashed computers, the rocket’s primary processor overpowers the rocket’s engines and causes the rocket to disintegrate 40 seconds after launch.

November 2000 — National Cancer Institute, Panama City. In a series of accidents, therapy planning software created by Multidata Systems International, a U.S. firm, miscalculates the proper dosage of radiation for patients undergoing radiation therapy.

Multidata’s software allows a radiation therapist to draw on a computer screen the placement of metal shields called “blocks” designed to protect healthy tissue from the radiation. But the software will only allow technicians to use four shielding blocks, and the Panamanian doctors wish to use five.

The doctors discover that they can trick the software by drawing all five blocks as a single large block with a hole in the middle. What the doctors don’t realize is that the Multidata software gives different answers in this configuration depending on how the hole is drawn: draw it in one direction and the correct dose is calculated, draw in another direction and the software recommends twice the necessary exposure.

At least eight patients die, while another 20 receive overdoses likely to cause significant health problems. The physicians, who were legally required to double-check the computer’s calculations by hand, are indicted for murder.

Guest-commentary-College-degrees-key-economic-success-Obama-s-education-plan-will-increase-access

• Customer Surveys
  - Sales and Premium
  • Amazon™ – Retails Sales that serves a second purpose of excellent product reviews
  • Ebags™ – Retail Sale site for luggage, and containers- an example of design and self improving review system

• Dedicated non-sales Review Sources
  • Epinions™ – another in the top 10
  • Consumer Reports™
  • Home & Furnishings
  • Autos: Foreign & Domestic
  • Age Demographics
  • Consumer Tools

• TV, Movies, Grass Roots
  • IMDB
  • Plugged In – A Child and Family Friendly Movie Review Service

• sqaforums.com
• youneedqa.com
• Bugzilla
• Mantis [eats bugs]·
• Cruise Control (builds)·
• Selenium Automation·
• Sahi web automation (browser independent)
  
• QTP: Geeks not spellers nor mere mortals
• W. E. “Kaizen” Deming· Odd Side Issues
• Web Sequence Diagrams

16 Critical Software Practices CD Online

16 CRITICAL SOFTWARE PRACTICES^TM

for Performance-based management

PURPOSE

PROJECT INTEGRITY
1. ADOPT CONTINUOUS PROGRAM RISK MANAGEMENT
2. ESTIMATE COST AND SCHEDULE EMPIRICALLY
3. USE METRICS TO MANAGE
4. TRACK EARNED VALUE
5. TRACK DEFECTS AGAINST QUALITY TARGETS
6. TREAT PEOPLE AS THE MOST IMPORTANT RESOURCE

CONSTRUCTION INTEGRITY
7. ADOPT LIFE CYCLE CONFIGURATION MANAGEMENT
8. MANAGE AND TRACE REQUIREMENTS
9. USE SYSTEM-BASED SOFTWARE DESIGN
10. ENSURE DATA AND DATABASE INTEROPERABILITY
11. DEFINE AND CONTROL INTERFACES
12. DESIGN TWICE, CODE ONCE
13. ASSESS REUSE RISKS AND COSTS

PRODUCT STABILITY AND INTEGRITY
14. INSPECT REQUIREMENTS AND DESIGN
15. MANAGE TESTING AS A CONTINUOUS PROCESS
16. COMPILE AND SMOKE TEST FREQUENTLY

This review does help me lean that-a-way…. yet I’ve spent hours today on Amazon and elsewhere reviewing different Android incarnations, none yet with v2.2, and with a daunting number of exceptions.  And all serious satisfied Android customers still give or take away “stars” based on the “iPhone platinium-iridium bar”.  One of the Android plusses, is so many choices…yet is a curse as well, since rush to market almost guarantees poor or incomplete QA

Sadly neither the customers, much less the OEMs (Samsung, LG, Nokia), seem able to handle so many variations without a massive migraine of industrial ADHD.

• I’ve tried so many “top rated” phones, and each has had some glaring blunder[s] … no, actually.. “evil compromise” that they deliver with the phone.
• My iPhone2 chose to omit cut/paste, promised, did not deliver voice dial. I swapped it for now-obsolete Motorola Z60 that was great phone but inept browser, that *did* sync with Outlook with a lot of “handholding”
• Then my most carefully researched and most beautiful Nokia E71 had everything you’d ever need, except a small system crash/shutdown when dialling.  Yep, they took the “no body will use this” shortcut with the PHONE part of their smartPHONE.
  It was a hardware masterpiece and a software, customer-is-idiot nightmare.
• Current reviews of Korean and Euro phones all have a near equal list of Pros and Cons.
• My Samsung Mythic shows equal or better design in the apt choice of name (mythic and elusive)
  ( spotty voice dial is 1000% better than Nokia’s or Apple, but 60% of Motorola’s 5 year old technology)
• “What the market will bear” to me means “what we will buy ignorantly, then put up with sheepishly“

I’ve got some waxed string on order. But am flirting with Ericsson’s X10, a used iphone 3gs or 4, HTCs 8181
If I expect my next phone to last for 3+ years, I may have to wait 3+ years. And for twice the value of laptop?
Apple seems to be the Volvo to Android’s Detroit (Beijing?) Big 5.

• ** January 23, 2011 – Update: I’ve gone over to the BSD side
  - Abused by lesser, cheaper, half-smart, half-fast phones, makes me a silly happy convert to iPhone4. Android tries harder and may catch up, but now is a lap or so behind in polish and User Experience. Most web browsers, except iPhone’s, do allow file uploads.
  • No matter that voice dial just takes off and calls Brazil without confirmation.
  • Nor that the keyboard may or may not work horizontally, and “auto-mis-corrects” typed words to some really embarrassing choices.  A textbook example of training the user to limp and like it.
  • Sadly alienated my Android friends, but now can hob nob with Apple apostles.
• Oh, indeed the iPhone is  a beautiful, well thought out computer (PDA?), camera, GPS system ….
  … with a neat near-afterthought Phone Accessory, wonderful voice mail and WiFi video conferencing (FaceTime).
• When they discover a workable human input device, and file upload, then it may even replace the PC for 90% of office  work…
• iPhone  replaced 50% of my email work yet gotten many laughs when I miss mistakes that  auto-correct introduces. Yes it can be turned off.
• It also has a fairly good Japanese IME with a spacebar that selects kanji, but can never enter spaces to accept a shorter / earlier choice.,

Lesson in Marketing 201 – Keep the consumers clamoring for just a few more features each new revision!

Opinion: Are We Raising a Nation of Fat Stupidos?

The latest global results on reading, math and science achievements have just been reported by the OECD. These educational achievements of young people are probably a pretty good leading indicator on how countries will fare in the 21st Century. In this article, these results are coupled with information on income inequality to draw interesting conclusions.

Education

The test scores for selected countries are presented in Table 1. They are ranked by the final column — the average score on all three subjects.

What do these findings tell us? Note the dominance of Asian countries at the top of the table. And note where most European countries and the U.S. end up. Europe and the U.S. had a tremendous head start on other nations. But now, does anyone in Europe or the U.S. really care about how well-educated their children are? These finding suggest the answer is no.

Does the amount spent per student in primary and secondary school influence scores? It does. For the 25 countries that the OECD has both scores and per student expenditure data, expenditures are positively correlated with scores and explain 47% of the variance in scores.

Table 2 provides information on average scores and total primary and secondary school expenditures per student for selected countries.

Does the pattern seen in Table 2 look familiar? For anyone who has read my pieces on US health care, it does. The U.S. spends tremendous amounts on health and education with a small return.

Education and Income Inequality

I hypothesize that educational attainment and income inequality are related: in countries with high income inequality, test scores will be lower. What is the basis for this hypothesis? In all countries, most students attend public school. But in countries with high income inequality, rich families will send their kids to private schools: and as a result, they don’t care about the quality of public schools and won’t want to support them.

What is the evidence? The Gini Coefficient measures income inequality. A Gini with a zero value means everyone has the same income. As the Gini increases, income inequality grows. Using a sample of 56 countries and data from the OECD, the Gini coefficient explains 22% of the variation in average educational attainment: as the Gini (income inequality) grows, educational attainment falls.

U.S. Youth

Two final points on young Americans:

1) Nearly 25% of students fail the written exam to join the U.S. military;

2) 75% of those aged 17 to 24 don’t qualify for the military because they are physically unfit (25% of American youths are obese), have a criminal record or didn’t graduate high school.

http://techcrunch.com/2010/10/05/ie-market-share/

Browser Market Share from techcrunch.com

• IE on decline, now under 50% share
• Chrome on the rise: now at 11.5% share

“As IE has been falling, rivals Firefox, Chrome, and Safari have been rising. But while both Firefox and Safari have had various growth spurts throughout the past two years, Chrome is the clear winner. The browser has gone from 1 percent of the market two years ago, to 11.5 percent last month. That places it well ahead of the older Safari (at 4.4 percent) and only behind Firefox (at 31.5 percent) and IE.”

On TechCrunch’s own site the numbers are different…probably due to its readers being more technology leaders.

http://techcrunch.com/2010/09/02/chrome-firefox-techcrunc/

• 15.65% is Safari
• 12.77% is IE

“The numbers are clear: Firefox is in trouble. It has been the top browser since we began using Google Analytics to record stats back in 2007. By 2008, it was nearly 25 percentage points ahead of the next closest rival, Internet Explorer. As of yesterday, it stood just 3 percentage points ahead of the next closest rival, Chrome.”