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AMD Could Profit from Buffer-Overflow Protection
spin2cool writes "New Scientist has an article about how AMD and Intel are planning on releasing new consumer chips with built-in buffer-overflow protection. Apparently AMD's chips will make it to market first, though, which some analysts think could give AMD an advantage as the next round of chips are released. The question will be whether their PR department can spin this into a big enough story to sell to the Average Joe."
Especially if the buffer is their banking account.
Like IBM with OS/2, they have the better product. They now just need to convince ordinary consumers that this is the case. For some reason, people love that little Intel jingle.
I know that people using standard APIs might be fine, but I can't help but wonder how many applications will not work because of it. While there probably aren't many self-modifying code apps out there, there are surely some. Will they be affected?
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They are protecting the pages marked as code from the data pages. Code could still overflow, but not use that to execute arbitrary code in the pages marked as data(or non-executable).
AMD's Athlon-64 (for PCs) and Opteron (for servers) will protect against buffer overflows when used with a new version of Windows XP.
This does require some interaction from the operating system in order to work. Hopefully AMD will release enough information to allow this feature to be implemented in Linux.
Where's my lobbyist? Right here.
I find it interesting that one of the reasons that hardware protection from buffer overflows is needed is because many programs were created using functions in languages that don't properly check array bounds. Programmers really need to learn that either they need to use functions which provide bounds checking if they insist on using a language like C or C++, or they need to program in another language.
(Note: Although many people come down on C++, it's also what functions you use. For instance, while fget() is considered "safe" because you provide a buffer boundry, gets() is considered unsafe. This drives me nuts! We knew how to program to prevent buffer overruns years ago, and they're still a problem!)
Sure, AMD just has to write a buffer-overflow exploit into a worm that carries the pop-up window message, "If you had and AMD processor, you're hard drive wouldn't be erasing right now."
From my reading of the article, this sounds like it's just a new spin on the per-page eXec flag on the AMD64 architecture.
:-)
Granted, yes, this is a good thing, but "buffer-overflow protection when used with a new version of Windows XP?" We now have to rely on Microsoft to set the X flag properly...
This has been talked about on Slashdot a lot in the past; the OpenBSD guys in particular are hot on the Opteron because it, like SPARC, provides this protection. Fortunately, this isn't some Windows-specific voodoo; we all stand to benefit from this fundamental fix to the broken Intel VM architecture.
Wraaaag! Why does everyone keep calling this a Microsoft bug?
Yes... the vast majority of buffer overflow exploits we read about are Microsoft based, however it's not too hard to find software from other providers, yes, even in Linux. Which can suffer from this kind of flaw.
Help Brendan pay off his student loans
Then the Japanese started making cars that didn't leak oil. Now, no one would accept a car that leaks oil. People have realized that cars don't have to leak and we shouldn't accept it.
It's the same thing with buffer overflows. People now have this attitude "well, there's nothing you can do. Just write code really carefully. Anyone who makes buffer overflows in his code is just a sloppy coder!"
Nothing could be further from the truth. There is no way anyone can code a large project in plain old C and not make buffer overflows. Look at OpenBSD, who are masters of secure C. They still have buffer problems.
And yet, there is absolutely no reason for code to have any buffer overflows! There are programatic tools, such as virtuams machines (think JVM) and safe libraries which mean that programmers never have to manipulate buffers in unsafe ways.
Putting in hardware-level support for this would be fantastic. It is time for people to change their attitude about what they accept in computers. Crashes and security holes are not inherent aspects of software. Mistakes are inherent in writing code, but these mistakes don't always need to have such disasterous consequences.
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What's about GNU/Linux's bugs or NetBSD's or Sendmail's bugs? This is OS agnostic.
This isn't insightful, it's flamebait and FUD.
They buy computers. They don't need to sell the idea to the Average Joe, they need to sell the idea to the people making computers for the Average Joe.
You probably shouldn't click this.
It's pathetic that AMD has to fix M$'s bugs...
How is this insightful? First of all, any post that uses the $ is Microsoft's name should be modded -1, 14 year old poster.
As if buffer overflows really had much to do with the OS. It has a lot more to do with poor coding. Try the following searches for more info:
linux buffer overflow
bsd buffer overflow
OS X buffer overflow
Solaris buffer overflow
And yes, everyone's favorite:
windows buffer overflow
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Some of today's problems are really just side-effects of the x86 legacy. If you're willing to break binary compatibility, fixing problems is really, really easy. For example, there's no law that stacks have to stupidly grow downwards in memory so that an overflow ends up overwriting older stuff on the stack space, instead of overwriting in the direction where the unallocated space is. And indeed, on many architectures, it works more sensibly. So even if you don't protect against overflows, their damage doesn't need to be so severe.
But by the time it became popular for personal computers to be connected to the internet (and thus, overflow protection started to become really important), it was far too late to fix the problem, because too many people were locked into x86.
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This existed in the 8086 and 8088 CPUs. You seperate your program into code, data and stack segments and load the appropriate segment registers. Code segments can't be read or written, data and stack segments can't be executed. But stupid programmers decided that that kept you from playing games with code-as-data and data-as-code, so they created flat addressing mode with all segment registers pointing at a single segment. Feh. Those who don't read history are doomed to repeat it. Badly.
Don't blame MS for everything. Unix too has a notorious history of its contibution due to buffer overflow. Ever heard of sendmail? I believe the first internet worm in 1988 utilized buffer overflow in number of unix apps including sendflow, finger, ...
Software can't do everything. In fact, some earlier architectures offered choice of separating data segment and code segment (DEC VAX were the latest I used which had this feature), but because they have some performance penalty, the hardware companies removed this feature. Now that we have more speed than needed, it is being put back.
For what it's worth... many processors, like the PowerPC series have had this "buffer overflow protection" feature for years. The idea is to mark program code pages after they are loaded as executeable and read-only. No other pages are marked executeable. It destroys clever little hacks like self-modifying code but at the same time, makes it impossible for buffer overflows to introduce new code into a programs executeable code page set.
The average joe can't even figure out that he shouldn't open email attachments from people he doesn't know (Exhibit A: MyDoom). You really think he knows what the fuck a buffer overflow is? "No buffer overflow? But what if I *want* overflow! More is better!" I applaud this security feature, but don't think of it as a selling point for typical users.
Exactly. OpenBSD 3.3 already came with this feature in May 2003.
"W^X (pronounced: "W xor X") on architectures capable of pure execute-bit support in the MMU (sparc, sparc64, alpha, hppa). This is a fine-grained memory permissions layout, ensuring that memory which can be written to by application programs can not be executable at the same time and vice versa. This raises the bar on potential buffer overflows and other attacks: as a result, an attacker is unable to write code anywhere in memory where it can be executed. (NOTE: i386 and powerpc do not support W^X in 3.3; however, 3.3-current already supports it on i386, and both these processors are expected to support this change in 3.4). "
I think a good commercial would having hackers trying to break into a computer, and then a big "ACCESS DENIED" error shows, and one of the hackers exclaims, "No good, they've got the latest AMD CPU!" And then some announcer says something like, "With the latest CPUs from AMD, your computer executes only what YOU want it to, not what THEY [flash over to image of frustrated hackers] want!"