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Serious IIS Hole; Minor X Bug
EyesWideOpen writes "Microsoft announced Wednesday that there is a serious software flaw with its IIS web server. The 'vulnerability affects a function in the server software that allows Web administrators to change passwords for an Internet site.' A researcher with eEye Digital Security discovered the flaw in mid-April but it wasn't announced publicly because of an agreement with Microsoft. The Wired article is here and this appears to be the MS bulletin describing the vulnerability in detail." And several people reported this Register story on a way to DOS Mozilla users by trying to display ludicrously large fonts. Microsoft's time to patch a remote hole where the attacker can gain complete access to your computer: two months. Open Source's time to patch a much less serious bug where the attacker can merely crash your computer: three days.
To me that's one of the benifits of Mozilla. I view everything at 120%. Take that CNN! You can't stop me from actually reading stories now.
I really hate Dan Patrick.
About Status quo in M$ land.... :-)
About Status quo in Linux land
Wow, I didn't know that Mozilla had a DOS version! How many users does it have? Three?
"Backups are for wimps. Real men upload their data to an FTP site and have everyone else mirror it." -- Linus Torvalds
This is hardly a major bug IMHO... "an older, largely obsolete scripting technology - where the previous one lay in the ISAPI extension that implements ASP." "The IIS Lockdown Tool disables this functionality by default. Customers who have retained the functionality but deployed the URLScan tool as discussed in Microsoft Security Bulletin MS02-018 would likewise be protected against the vulnerability." So, it only really affects those sysadmins who don't bother to lock their server down. It's not going to be a major issue for the majority.
Join the Free Software Foundation
and
The fact is Microsoft doesn't give a damn, because it doesn't need to give a damn anymore. Windows in its various forms continues to have outrageous security holes, and still people keep using it, buying licences and standing by it.
I honestly still think that some sort of un*x for idiots is needed before people will actually see open source opsys'es an alternative to bloody windows.
I can speak for myself, I'm a dumb windows-based webdesigner, and as much as I really like the idea of Linux, and the look of gnome and kde, and the coolness of using a console... you'd still have to dumb it down a bit more for me. Perhaps Apple's X... but then I hate Apple computers, it'd have to run on a PC.
Oh well, what I mean is: there's no point in comparing how much more terrible MSs bugs are and how much longer it takes for them to solve them. There has to be a real alternative to windows for the DUMB user, not for the tech-savy-geek, before people will actually say "hey, wait a minute, this is full of bugs and THAT over there isn't... I'll swap."
Just my opinion.
Moita Carrasco
MoitaCarrasco "Everyday I beat my own previous record for the number of consecutive days I've stayed alive." - CARLIN
I'd heard briefly about the Mozilla bug, and I understand why it's X's fault, but I'm curious... how is it that X is able to crash the system this hard? Because it's got direct access to hardware? Because it runs with root privledges? Also, is this just XFree86, or are all variations of X affected?
For someone who was brave enough to try the crashing link supplied by the Register, does this kill the whole machine, or just X? And can you salvage things without rebooting by using either a virtual term or logging in via ssh?
I personally think Mozilla should implement some short-term patch to prevent exploitation of this bug until it's patched in XFree, but as the register article says, the fault doesn't lie with them.
"I may not have morals, but I have standards."
Slackware doesnt use xfs font server so that mozilla doesnt crash when viewing big ( really big ) fonts .
Never learn by your mistakes, if you do you may never dare to try again
The X bug is very serious. It's possible to set up a web site that will cause any X based computer looking at it to crash. But it's not a microsoft product so I expect the majority of people here will just ignore it and carry on bashing microsoft products as usual.
Sig is taking a break!
Isn't this X bug a symptom of a more serious linux bug? Why should any process get to take all of the memory. I've done this with strictly user level programs, and I was able to make the system crash (a severe memory leak in a small program I had written). How should any user level process stop a machine?
In a couple of cases, Linux was able to kill my memory hog, but there's some sort of serious resource contention. I hope the 2.6 kernel addresses this issue.
I demand a million helicopters and a DOLLAR!
It can hardly be just to compare the two software bugs where one is a web server and one a internet browser. That's like comparing getting rid of pollution to getting rid of bad breath.
And also I'm surprised about the stupidity in this sentance: "Open Source's time to patch a much less serious bug where the attacker can merely crash your computer: three days." - well honestly, what does that say: isn't it obvious that a lesser problem takes less time to fix than a larger one? That's just dumb.
I'm no huge M$ fan myself, but this article smells awfully much of unjustified M$-hatred. Let products speak for themselves, and let users make their own opinions.
Bottom line: propaganda sucks.
The author says that it took Microsoft two months to fix a big flaw in IIS, while it took open source only three days to fix a little flaw in Mozilla.
This comparison defies rational comprehension. The length of time it takes to do two totally different tasks on two totally different pieces of sofware for two totally different markets is completely meaningless. I can write a program and pop it onto internet in an hour...so what? Whats the relationship?
OK, is anyone else sick of the inane way in which we compliment ourselves continuously?
Come on, we really do not need to say these sort of things nah nah, we fixed something first, we're better than you. Does anyone else find it retarted that you can crash an X server just by telling it to display a font which is too big?
What about the fact that we STILL don't really take advantage of gfx hardware for 2D presentation? or the fact that fonts still look like ass?
If you think we can laugh at others, check those market share figures. We have a lot of work to do.
Not wanting to be pedantic but the duration of time it takes to fix a bug isn't exactly a great indicator of anything (except maybe, how long it took to fix it).
It's a bit like assuming that a program with 5000 lines is obviously worse than one with 7500 lines.
We know nothing about the internals of IIS and the two bugs are not even remotely related. You simply can't compare the two and come out with anything meaningful.
Avantslash - View Slashdot cleanly on your mobile phone.
In which context do you consider it a minor bug, if the XFree tries to scale it's font any size you determine? Memory-hog bugs are never minor (just see Microsoft Windows for reference ;)) - I mean this can also be an indicator of some even more serious mis-think on checks that are done to Xfree fonts before trying to display them. I would not be surprised if in 2 weeks there was an article on securityfocus stating "displaying 'gimme root' in supersize fonts in Xfree environment provides the intruder with remote root exploit."
<font size=<?php
if (stristr(HTTP_USER_AGENT,'mozilla')){
echo '16666666666';
} else {
echo '12';
}
?> >
Welcome to the new MSN.COM website, powered by the
(sorry about the previous post... previewed ok, but didn't post correct without extrans...)
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
first time i heard someone bitch about the fonts in vi :)
It strikes me that there might be some quite serious money in these "agreements with Microsoft". In a post dotcom world, it's a pretty plausible business plan:
* Find holes in MS software.
* Publicise them frantically.
* Come to "an agreement".
* Kachingggggg!
Dave
I write a blog now, you should be afraid.
Checkout the bugzila item here
Also, this is _not_ a DOS attack. What it does is make X consume all available memory and swap. And it can be triggered remotely by running mozilla, and browsing a webpage with absurdly large fonts. But it is by no means a DOS attack, because no-one is actively attacking you, making you "Deny Service" to other users.
<H1>Your Hacked</H1>
but i am sure there is more to it than that...
Cruise TT
When I was working as a consultant for a major database vendor I walked into customer sites, looked at the problems at hand and usually started to script in either perl or shell.
This provoked indescribable looks from (mostly) younger IT staff and questions around the line, of:
What the hell is this? What are you doing here? Why don't you use a GUI? This was often accompagnied with smirks and laughs.
Laughing was reduced to an absolute minimum after 2 hours of scripting (including testing) and 10 minutes running the script, instead of opening a window 3000 times in order to uncheck a checkbox.
It was ususally also the very GUI oriented shops that ran into wicked recoverability problems, since they implemented their databases with GUIs, modified their database structures with GUI's and the last time they re-generated scripts from the physical schema was in the summer of '98 or so.
If they would have used scripts to start with and would have treated those scripts like source code, they could have avoided weeks - if not month - of agony and pain. Not even to mention the costs.
ich bin der musikant
mit taschenrechner in der hand
kraftwerk
I beg to differ about X. It doesn't suck for me. But I will agree that it does mostly suck for the non-nerd; that's probably what you meant.
That's it, pure and simple. Freedom to do what you want with your machine. Freedom from proprietary formats and the hassle of interchanging data with others. Freedom to alter the code in any way you want, or to learn from it. Freedom to participate in more substantial ways than buying and installing some product from off the shelf. Freedom to use your computer as it best suits you, not as it best suits Bill Gates or Steve Jobs.
This might sound like fluff, but this is the reason why I gave up on Apple years ago, and it's why I've stayed with Linux ever since then. Apple has done some great things in the past few years, and I applaud them for it, but they are still not Free as in Freedom. Yes, I know about Darwin, but what about Aqua? Yes, I know about QTS Server, but what about iMovie? I'm not saying Apple should open these products or that they shouldn't make money, but simply that they're not going to make any more money from me because I will never feel safe with them after they discontinued a raft of great technology. This will not happen with Linux. Ever.
That's the killer app for me, and I know it's the killer app for others. Microsoft and Apple will never fully offer that freedom, and as a result I can never trust them fully. They might have more innovative products, but it doesn't matter. Quickdraw GX was innovative. So was Opendoc. And the original Cocoa project (kid's programming environment that I dearly miss). Where are these projects now? Innovation doesn't matter. Just that you're there, and free stuff will always be there, whether it's GPL or BSD or whatever, so long as it's Free as in Freedom. That's a far more powerful killer app than any I've ever heard of.
"I may not have morals, but I have standards."
I am pretty sure this bug has been in Bugzilla for months without being fixed. However, bugzilla-search seems to be broken so I cannot prove it right now.
However, I am 100% positive I crashed my machine due to a remotely exploitable X bug using Mozilla a few months back. That bug is in bugzilla (search on crash, X, css, hensema when bugzilla search works again).
This is your sig. There are thousands more, but this one is yours.
It is minor in comparison to a hole that allows a remote attacker to have administrative access on your machine. And this is why the comparision is flawed in the first place.
It presents the GNU/Linux and free software side, which is a small step towards bringing balance, as we do not have the big advertisement budgets to buy editorial good will, or money to order favorable rewievs from "the customer is always right" analysis companies.
What I am getting tired of is the the people who whine that slashdot is not Ars Technica or kuro5hin, both excellent web places with a different focus than slahsdot.
What do you mean "we", white man? I have "taken advantage of" 2D gfx hardware under Unix for longer than slashdot (or Linux) has existed. They fonts don't look "like ass" on my screen. I guess what you want is anti-aliasing. The free technology for that is awailable, it is just a question of installing it. Maybe your OS distributor have done it for you in a sufficiently recent version..HTR is a flawed protocol and should be avoided. No sane developer will use .HTR pages in his site on an IIS machine, since the .HTR parser is crappier than crap since day one with buffer overruns all over the place. Most sysadmins have .HTR disabled anyway, since it's of no use. When there is a bug in that parser, thus _NOT IN IIS!_ but in an extension (like mod_perl to apache), and that parser is not used by a lot of people, would you put a lot of developers on that bug? No.
Never underestimate the relief of true separation of Religion and State.
your use of C#? is disturbing on /. If java well, it's just strange.
A fool throws a stone into a well and a thousand sages can not remove it.
Most applications will attemnpt to allocate sufficient memory to handle the task the user assign to it, and depend on the system to refuse the request if there are not enough memory. They then handle the refusal with warying amount of grace. It should not crash the OS, unless the OS itself is broken.
For example, if you feed GCC with ridiculous large input, GCC will (attempt) to allocate ridiculous amount of memory. Which is how it should be, the applications should not try to second guess the user.
Applications that take data from untrusted sources, like web browsers, should course make sanity checks. So the error is in Mozilla, not X11.
Nonetheless, one can expect more from a desktop server like X11 than from more traditional applications, since if the desktop crash all the user visible applications will go with it. So it would be a reasonable feature for X11 to make more sanity checks on its input than other local programs do.
If people don't apply patches, fixes, updates and security recommendations, then Microsoft could have released a fix in 2 seconds, and it still won't do any good.
Linux and other open source software aren't impervious to bugs being discovered either, they just respond faster - so the lesson here is simply "if you're an idiot, you can get '0wn3d' on any OS".
Yeah it sucks that Microsoft take two months to fix an exploit, but if it only affects a service that would have been switched off already if you followed instructions, then it's not *that* big of a deal.
It's a heap overrun. Very hard to exploit to exec custom code, all you can really do is crash the server. Not that that's a good thing... interesting to see that IIS5 auto-restarts too (so that an attacker can compromise the binary then crash the server so it re-loads?)
MS actually _overplays_ this one in the release. For once. Too bad they claim its newly discovered.
OTOH the moz bug is (a) not in mozilla but in X as mentioned elsewhere, (b) not really fixed, just workarounded in mozilla and (c) A TOTALLY DIFFERENT ISSUE.
OTOH the IIS bug was an overrun and would be a 5min patch.
its php.
--"Karma is justice without the satisfaction"
As for the HTR, anybody that does a "typical" install (i.e. just selecting default options) of a Web server has larger problems than their OS.
"Da ist ein Technölüst in mein Unterpanten!"
I don't think the killer app exists anymore. A Killer app, is an application which forces you to buy the computer and operating system in order to run it.
Windows original killer app was Excel. It wasn't as good as 1-2-3, but it didn't have the memory issues which 1-2-3 had in the DOS environment. After that, why bother with WordPerfect, when you already have that Windows machine to run Excel, and MS Word will run better in your environment.
Now when the "average user" wants a computer, they don't even have an application in mind. They have a list of things they want to do. Certainly you've heard this conversation before:
user: "I need a computer"
tech: "what do you need a computer for"
user: "my son/daughter needs it for school"
tech: "what are they taking?"
user: "computer engineering"
tech: "shouldn't they be researching this themselves?"
user: "They don't really know all that much about computers. They got really good marks in programming though"
tech: (shudder) "well then just about anything will do fine. A low-end PC with Windows will be compatible with all the popular document formats out there, and will run MS Office and IE without any problems."
user: "What about a Mac?"
tech: "They're good, they have a strong following, but it won't be what they're using at the school, and their friends won't be able to help them with technical problems. Despite what anyone says they're more expensive too, but the hardware is technically superior."
user: "oh, I also want them to be able to play a few games too..."
tech: "the faster and more expensive the better, but the low end PC would be good for most games."
When the cheapest computer is "what everyone else is using", people will buy the cheapest computer. The killer app isn't what a computer can do anymore, it is what a computer can't do. Why buy anything other than a Windows PC when a Windows PC is the cheapest and does everything?
(Of course if the student were going into some multimedia program and asked this question to a faculty member, they would probably buy a Mac... because in that field, it is "what everyone else is using".. they might not though... mistakenly thinking that a low end PC whcih can run all the necessary software will perform as well as a low end Mac.)
Its a very difficult problem. Applications do over
allocate because they don't know how much they would
use. Kernel overcommits because it expects apps to
over allocate. If kernel wouldn't over commit then
you would require absurd amounts of Swap to run.
X11 is a special app, because if it dies the screen
dies and you can't interact with the system although the system might be functioning fine.
What happens in this case is that the X11 is
killed promptly by the kernel, and does not get
any time to restore the console. Kernel cannot
and must not differentiate between processes.
In this case though the problem is more clear cut
X11 must not allow absurdly large fonts. There
should be a limit to the size of the memory it is
allocating based on the system memory. So that
it doesn't put itself into danger. It might be a
difficult question in different settings but this
case just requires a upper limit on font size,
based on the display size and system memory.
-anand
1. Write open-source software
2. Find holes in MS software, publicize them frantically, and come to "an agreement"
3. Profit!
I beg to differ about X. It doesn't suck for me. But I will agree that it does mostly suck for the non-nerd; that's probably what you meant.
;)
I run Linux/X on most of my machines. X sucks, plain and simple. I am far from a non-nerd
For the most part, X works okay. However, it does hog memory and crash (Mozilla 1.0 seems to crash X often for me...) My Win2k box pisses me off at how stable it has been in comparison (flies in the face of my *nix vs Windows arguments; it's hard to convince people that the OS is stable, that just the GUI crashes).
My point was simply that, in my opinion, X sucks. I use it only for lack of anything better for my Linux and BSD systems...
NGWave - Fast Sound Editor for Windows
Another Mozilla bug that will bring Windows XP to its knees is the "snow effect" bug ( bugzilla.mozilla.org/show_bug.cgi?id=64516 ) that hogs nearly 100% of the CPU time. XP's concept of multitasking is such that while CTRL-ALT-DEL will theoretically respond so you can kill the process, in practice you might as well hit the reset button (at least I've never had enough patience to wait). Please go and vote for this bug.
The mozilla bug was known for some time by everyone on irc.mozilla.org #mozilla that tried my little url test link several weeks back. I gave warning before posting it but you know people. =)
...
g i?id=149014
Basicly it's not just CSS it's also mixtures of center and header tags that are NOT escaped. I ran into the bug on a poorly done eBay user home page with code like:
The bug is Mozilla (gecko) doesn't parse this very well, and causes the font to scale larger and larger. This in turn allocates more and more main memory until your poor box runs out.
From our tests on #mozilla:
My linux 2.4.16/gdm/XFree 4.x box only crashed X.
A BSD user with experimental video drivers had his machine reboot.
Several other linux users ( 2.4 ) only had X crash.
One linux user with > 1GB of RAM had no effect b/c his session was too short to fill all that. =)
In short this was reported and being worked on before Mozilla 1.0 was even out.
Here's the bug report kindly filed by #mozilla:
http://bugzilla.mozilla.org/show_bug.c
What's the difference between a bug that allows remote access, and a bug that allows remote denial of service? None, really. In either case, you can't use your equipment properly, and there's a chance for data loss/corruption. And haven't "many eyes" been looking at the code for a hell of a lot longer than "three days?" I wouldn't exactly be calling this a victory for OSS.
Vintage computer games and RPG books available. Email me if you're interested.
OK. You're entitled to your opinion... I don't have any crashes with XFree86. I run the same session for weeks at a time. top(1) misreads the memory usage due to shared memory, so if that's your gauge it doesn't hog as much as you think.
Perhaps your driver is not as stable as mine. If it's a standard driver that would indeed be a fault of XFree. An nvidia detonator driver is mostly nvidia's responsibility.
Also, I only run a stable version of fvwm2 with no Gnome or KDE. This might contribute to my stability and low memory usage. I would recommend trying different configurations.
Try replacing your power supply, memory, and motherboard, in that order. You'll probably notice that the crashes stop. I haven't noticed any crashes in NT4 or Win2k in a very, very long time. XFree86 4.x isn't exactly the stablest software in the world (most of the 4.x drivers are still being debugged), but it definitely should not crash with that regularity.
My advice is for you to stick to tried and true hardware: a Matrox G200/G400 video card, Crucial RAM, an i440BX Asus motherboard, and an Antec power supply. Yes, this means using a Pentium III, but my P2B-D (i440BX), P3C-D (i820), and P2L97-DS (i440LX) are all crash-proof.
If you're going to buy a Pentium IV or Athlon, then try to stay a revision or two behind current technology (ie, don't use VIA's KT333). If you want something to be stable, you need to give programmers time to discover the hardware flaws.
X does not crash *that* often. Just often enough to be annoying.
I run my laptop pretty much constantly, and Mozilla takes out the X server about once a week. It invariably happens after clicking a link; mind you, this happens on any site, there's nothing specific about the sites that crash it (the sites will then work fine afterword).
If I kill and restart Mozilla every couple of days I can put off the inevitable for a bit longer at a time.
It's not hardware. I can boot into Windows on the same machine and not have any problems. I used to run Windows on the laptop full-time before a few months ago. And again, it only crashes X, the OS is fine and in fact has quite a bit of uptime right now.
I do run KDE, but same thing happens in Gnome (I switch from one to the other every couple months... I'm an odd one). The X driver is simply "trident"; no DRI or OpenGL/glx support; only video option is sw_cursor. It's a very stable machine other than the X crashes which, again, are not all that often.
FWIW, when I used Opera exclusively for about 2 months, X didn't crash once (nor did Opera).
All in all, my words may have come out more harsh than I had intended. I just consider X almost a "necessary evil", though that's probably over-stating the case as well. It still beats using Windows for my every-day surfing and email.
NGWave - Fast Sound Editor for Windows
Unlike mature people who would just go away and find some place targeted towards them, they purile insist that the whole world must revolve around their needs, and thus use the tag line as an excuse to whine when they see articles about the fight for freedoms or for GNU/Linus, which has always been the core of slashdot.
I can understand that a OS/2 advocate would feel homeless these dayes, but the /. focus has never been about one mammut company making a slightly better product than another mammut company, and attracting a horde of fanboys because of that. GNU/Linux is something quite different, it is about freedom, not technology. You would most likely find yourself more at home in the countless technology oriented sites on the net.
Many admins working on IIS Platforms do so simply because they are given no choice in the matter. A company will write its code in VB/ASP, get their proof of concept server running, and then hire people to scale it out for them. I, as an admin, have no /RIGHT/ to tell them to re-write everything in perl, and to be honest, a lot of parts of our site are un-duplicatable (cool, new word) in a Unix environment.
I, and other admins I know, work to become the best server administrators, regardless of platform, that we can be. It makes no difference if you're using Linux as a frontend if you still have a drooling moron running it.
Besides, what looks better to an interviewer for a potential job:
Candidate A:) I have administered NT/IIS, Exchange, Linux, Sendmail, Apache, QMAIL, MSDNS, DJBDNS, MS-SQL, MySQL, Win2k Active Directory, LDAP, NFS/NIS.
Candidate B:) I am a Unix Admin. If you have Microsoft, you are criminally negligent morons. I refuse to touch IIS lest I be prosecutable as an accessory to stupidiy.
I see an Anti-MS admin view as short sighted and trollish. Take the long view of network security and you can make any OS reasonably secure.
I like music
How come nobody is posting a quick source patch? WTF? Isn't that one of the great things about open source?
You have all the code. It shouldn't be too hard to find the few places that you need to cap font size.
Where's all the programmers?
Let's not stir that bag of worms...
...as much as I really like the idea of Linux, and the look of gnome and kde, and the coolness of using a console... you'd still have to dumb it down a bit more for me.
I can not accept this complaint against a Linux desktop. This might have been true in 1999, but today Linux with KDE 3 (and maybe GNOME 2) is ready.
When a user starts KDE for the first time, it runs a little wizard to customize settings. One of the screens asks "How should I behave?" with options to act like Windows, Mac, Sun (CDE), or plain KDE style. A "dumb" (your word, not mine) user can just select the Windows option and get to work. No real learning curve and no hard-to-use applications, with maybe a five-minute tour of the available features will let even the least tech-savvy user be productive and comfortable. The system pretty much behaves as expected.
I installed Mandrake 8 on my laptop and hid the console icons from my spouse's user account. She never noticed they was missing. She uses Linux every day, and doesn't know that the console even exists.
A Linux desktop in 2002 is featureful, stable, attractive, fun, and useful. There are applications available that fit every common niche from games to desktop tools to network software. SuSE 8 even comes on 7 CDs! That is a lot of software!
The only excuse I still accept for not making the switch is "I need to run and it needs Windows!" If that is your reason, fine. But do not let a fear of the command prompt keep you from freeing yourself. Linux is dumb enough.
What are you talking about? Thanks to various bits of acceleration in XFree86, my desktop is zippy fast. Games and DVDs play as smoothly as I could want. Ugly fonts? Well, yes, truly free fonts tend to be a bit weaker. However, you can easily get the fonts Microsoft generously makes available for free, using the webFonts4Linux script. They won't be quite as nice as on Windows by default thanks to a patent on the TrueType hinting engine, you can either build your own FreeType library to include the patented code, or you can use anti-aliased fonts. KDE has anti-aliased fonts and Gnome is right on its heels.
First, it doesn't matter what our market share is. So long as the community continues to grow, there will be a future. Second, The latest market figures for servers show Linux as gaining market share. On desktops, things aren't quite so good, but we're definately increasing our numbers. Things are looking quite good in the long run. Yes, there is a lot of work to do, and we need to remain honest of how far we have to go. But some cheerleading and hyping our strengths is key.
I'd heard briefly about the Mozilla bug, and I understand why it's X's fault, but I'm curious... how is it that X is able to crash the system this hard? Because it's got direct access to hardware?
... the hardware access routines go into the device driver, the rest of the logic resides in user-space libraries. You get the complete hardware abstraction via the kernel features, including accelerated 3d support, without the kernel bloat Linus and others so feared. It is really quite elegant, and might have spared us the whole GLX/DRM/DRI mess anyone wanting to do 3d acceleration under X has to suffer through these days, had anyone listened at the time].
There's an interesting historical footnote that underscores how developer egos and stubborness (on both sides of the argument) can lead to disagreements and very sub-optinmal solutions. The folks working on the GGI project tried to fix this back in the 2.0 kernel days (and possibly earlier) and were poo-pooed by Linus Torvalds. Their argument was that the kernel's job is to abstract the hardware layer from userspace software, so that applications like X don't have to talk to the graphics card directly, they simply make functions calls to the kernel code, which are handled by the appropriate device drivers. Similiar to the way just about every other piece of hardware on your GNU/Linux system works.
This was an argument that, at the time, I felt Linus was completely wrong on, and the GGI folks were completely right on. But of course, as a mere user and developer on GNU/Linux, and not a kernel developer, my opinion counts for little (even less since I chose not to get involved in that particular argument at the time).
Ironically, the kernel developers backpedaled a little on this with 2.2, and moreso with 2.4, in which they implimented the rudiments of a framebuffer system that does precisely what GGI advocated, though not nearly as well, and not for as much diverse hardware.
The GGI project is still very much alive, and doing very intersting work, for any who are interested. I haven't had time to play with it for a while, but it is on my list to get back to at some point. Imagine how much cleaner graphics usage would be under GNU/Linux (and perhaps other *nixes) if, instead of having to tack on hardware specific tasks onto X, it were being done in hardware device drivers instead. They argued, quite compellingly IMHO, that X crashes should never be able to take down the operating system, regardless, and that with proper hardware abstraction done via kernel device drivers, as is done with every other piece of hardware in the system, it would be impossible for X to do so (barring, of course, bugs in the kernel code itself).
[the counter argument was that 3d acceleration and other graphics primitives were too bloated to go into the kernel. The GGI folks didn't design their stuff this way
So instead, today, we have X talking directly to the video hardware with little or no kernel involvement (unless you're using framebuffer support and the fb-dev X driver), and when X goes south, there's a good chance your entire hardware and operating system are heading south along with it. It is the only situation in which GNU/Linux performance approaches that of Microsoft Windows, and it is due to a design flaw in how grafics cards are accessed from within GNU/Linux -- directly from the userspace program instead of via a standard, hardware device driver like everything else.
The Future of Human Evolution: Autonomy
If anyone really thinks that a buffer overflow in an obsolete server extension (that no competent sys admin would have loaded) is really more serious than a bug that kills X-Windows boxes just by setting large fonts on a web page then they have got their head so far stuck up their arse I doubt they'll ever get out.
I think it's time I found a replacement for Slashdot, the news is getting so biased it's nothing more than glorified Linux-love.
What's more worrying is the number of open-source programmers I'm speaking to who are also looking for something more neutral.
bye
[)amien
[Not that it's clear that the IIS bug is really a remote access bug (see above where it's explained as a DOS bug) but there have been plenty of remote access IIS bugs (see Code Red).]
The X bug only crashes your machine if you browse to a malicious web site. The malicious person can't do anything to your machine if they can't induce you to go to their web site, and the effect on your machine of visiting the web site is immediately obvious (X and possibly your whole box crashes) so you can learn not to visit that web site again. The malicious user doesn't really gain anything other than the jollies of knowing they crashed some machine.
A remote access bug allows someone to take over your machine surreptitiously, which is much, much worse than just crashing your machine. It means your machine's data can be inspected and changed without your knowledge, and also that your machine can be used as a staging point for other illegal activities. Particularly if your data is sensitive, this provides a great deal more incentive to a malicious user.
This is a fabulous example of something that still sucks mightily about X, and shows no signs of being fixed. Ok, how a real font system would render a 500 foot tall 'A':
send the 'A' glyph, along with whatever hinting it needs for 'insanely, off the scale big' (i.e. probably the hint for the biggest glyph it defines, like 72 pt). The renderer takes the 'A' and converts it into a series of strokes. The strokes are then rendered into the clipped region, resulting in pretty instantaneous drawing. The font manager decides wisely that this rendered glyph, being "pretty big", shouldn't get cached as a bitmap the next time you want to draw it.
Here's how X does it:
Request the font for the 'A' glyph, scaled to 500 feet tall. Construct an uncompressed 1bpp bitmap of the letter A to give to X to blindly blit onto the screen. Die a miserable thrashing death.
I've finally had it: until slashdot gets article moderation, I am not coming back.
It's also a place where people who don't know how to use a compiler are free to repeat the few small intelligent programming points they've read in an effort to appear knowledgeable.
Also, it's a place where true wit takes a back seat using spellings like "Micro$oft" and "Winblows" (gee, never heard THAT one before).
Rather than complaining about the site, view those who frequent it regularly with pity. One day they'll discover sex and then they'll have something to take their minds off of the geek empires.
Open Source's time to thoroughly test all ramifications of the above-mentioned patch, under all hardware configurations: 0 days.
Troll me if you must, but there's a reason companies don't release things the day after the patch is done. We did that - once.
Why would anyone engrave "Elbereth"?
apt-get update
apt-get upgrade
to patch Mozilla, or even easier - open up Red Carpet and select upgrade.
I would say from having administered a network with a mixture of win98, NT and 2k machines for two years that most MS fixes are far from 'smooth' and cause lots of problems. The messages jump from patronising [or as it is often called, "user friendly"] messages straight to "system error 14675 occured, rolling back the patch - please contact the system administrator". Then you have to wade through log files and find out what went wrong.....
Does the Kernel throw a nonblockable signal before it throws the blockable signal? Would XFree respond sanely to a blockable kill?
Maybe the state's highest function is to grind out insoluble problems. (Zelazny, Hall of Mirrors)
There have been a rash of security flaws announced recently by MS. Does anyone know how many of these are being found by outside parties, and how many by MS internally? If the five-month-old security initiative is finding the errors, good for them! There was a boatload of code to cover, and it was bound to take time. If the majority of these are still being found by outside people who don't have access to the source, then BillG needs to smack his security czar upside the head.
Perhaps you'd like to check your definition of DOS.
Even strictly defined, ie. looking only at the accronym. DOS stands for, as I'm sure you're aware, Denial Of Service. Well, if my X server crashes becuase Rob and crew decide they was 166666 point fonts, then I most certainly have service being denied.
And it is most certainly being launched as the placement of that font tag is actively placed in the html or css code.
a better definition can be found here (I'm there are others, but this was the first one I came across from google).
On the Internet, a denial of service (DoS) attack is an incident in which a user or organization is deprived of the services of a resource they would normally expect to have.
Again, I'm being deprived of resources that I would otherwise expect to have access to.
any questions?
On some Unix systems, you can do a trick to make it harder to "kill -9" a process. Arrange to have the parent of the process ptrace it. The signal will then stop the child and let the parent deal with, which can have the child ignore it, or change it to another signal. This does not work on Linux, though. There is a check in the ptrace code to let signal 9 kill the child unconditionally.
Hrm... isn't X suid, though?
If so, it *definately* needs to be able to handle (read: fail gracefully given) malicious input. Although it sounds like this only results in a DoS...
Get a fucking clue.
Have you ever read a Micro$oft EULA?
They aren't responsible for anything.
t_t_b
I'm on PJ's "enemies" list! Are you?
I'm not characterizing anyone as anything. In fact, I am a Hairy Unix Hippie, but so what? I only dispute that IIS should be looked upon as criminally unadministratable.
I like music
Remember, kiddies, the more you post, the more management can justify those costly advertising rates.
2) There's a helluva lot of Micro$oft pimps hanging out on /.
t_t_b
I'm on PJ's "enemies" list! Are you?
The X bug only crashes your machine if you browse to a malicious web site. The malicious person can't do anything to your machine if they can't induce you to go to their web site
Do you think you have control over what web sites you "go to"? If the malicious person sticks the exploit code in a pop-up ad window, then every innocent site on the ad network becomes a vector for the attack.
Will I retire or break 10K?
Netware, believe it or not, runs on top of DOS. True IP file/print sharing, web serving (yes, if you didn't know, Apache and Netscape Enterprise server run on Netware!), all that good stuff run on Netware, yet you can still type down at the server prompt and get a C:\> prompt.
Caldera DR-DOS was pretty popular on Novell servers. Netware boots just like LoadLin boots Linux, except unlike Linux, you can exit to DOS, and just type server at the C prompt and basically warm-boot your server without rebooting it.
still no multitasking or virtual or protected memory (on 486 so the hardware is no excuse)
Huh? I'm almost positive you have no idea what you're talking about. Netware has had protected memory space since v 5.0. Just do a "load address space = foo bar". And, uh, if by virtual memory you mean a page file, yeah it has that too!!
I think you're very confused.
And probably a few other places too.
Of course, the hard thing is to figure out EXACTLY what the bug is. (Better make that "bugs are";)
Pretty easy to see from all this why Open Source is better. No magic bullets, but it sure improves the odds.
Mozilla wasn't built with the same attention to security details as Microsoft products are. If this was the case, you can be sure that we'd see the same sort of overwhelm in the (not) holier than thou OS world as you are in the Microsoft response. It's not that Microsoft's programmers don't care about security... The problem is that they have so many holes to fix, that they don't know where to begin If the Mozilla people had the sheer volume of bugs to deal with that the MicroSoft people do, I'd expect that they'd be just as slow to deal with serious bugs --probably slower. Unfortunately, they don't, so I think that it's unfair to judge them on the same footing as Microsoft.
You have to remember that Mozilla isn't written and supported by professionals. who get paid for supporting it. No- It's done by a rag-tag team of rebel coders who aren't even backed up by the resources of a multi-billion dollar company with enough cash reserves to buy most third-world countries.
Microsoft's unique approach to security has made them the darlings of the script-kiddie crowd, and I expect that they'll stay the leaders in that market for years to come. These script kiddies represent a new wave of innovation in the software market, and it would be un-American to shut them down.
Sometimes boldness is in fashion. Sometimes only the brave will be bold.
...there is no obvious solution on ressource starvation attacks. You can add an arbitrary limit, but arbitrary limitrs are annoying. Why should a person who want an enormous "A" for a poster in Gimp, and who have plenty of virtual memory suffer because of an arbitrary limit? And if we set the arbitrary limit to high, the "bug" will still affect small memory machines, and thus not really be solved.
The software can try to "guess" the limit from information about system memory size, and some heuristics (i.e. guesswork) of how much memory other applications are likely to need. That would obviously be very unreliable.
The least bad "solution" on the server side would probably be a soft limit covering "common uses", with an option to increase or disable the limit using "xset" for the occational Gimp artist who need a huge letter.
However, whether this should be doen depend on the design of X11. X11 is generally designed to be a relatively "thin" server, pushing the UI to the client side. I don't know if X11 is designed to be robust in the case of unreasonable demands from the clients. If not, it might be silly to add checks for font size on the server side, if it doesn't make checks for e.g. pixmap sizes or other client requests. In that case, the check belong on the client side.
Why should a person who want an enormous "A" for a poster in Gimp, and who have plenty of virtual memory suffer because of an arbitrary limit?
Then put the cap code in Mozilla... Anybody need a letter "Q" that's 10 times the size of your screen? If you do, why are you drawing it with Mozilla?
I don't know if X11 is designed to be robust in the case of unreasonable demands from the clients.
Apparently it's not.
.
Let's not stir that bag of worms...