Sorry, but if anything that simple can cause root access, then that’s a general error of the architecture and kernel.
By default you need root access (or an exploitable bug) to map page zero into your address space, and you need to specifically configure the kernel to allow it, and then you need an exploitable kernel bug to make use of it.
But if this gains you root access without you actually having it, it's a fault in the OS security. You cant rely on programming languages to protect against such methods.
Except you need root access in order to map page zero into your address space, and you generally need root access to configure the kernel so that it will allow root to map page zero into your address space (Wine in Ubuntu used to set the minimum mmap address to zero, I'm not sure whether it still does). So to get root access in this way you either need root access or multiple userspace vulnerabilities. And then you need a kernel flaw which executes code relative to a null pointer.
So while it's interesting and something developers should be aware of, it's not really a serious security threat in most cases; the last use of this exploit that I'm aware of required a kernel bug combined with a pulseaudio bug combined with an SELinux bug.
Strange: I found it a mind-numbingly boring examination of evolution in action. And I normally like Ang Lee movies.
The real reason why Hollywood movies 'cost a truckload of money to make' is that they pay $200,000,000 to Big Star Of The Moment(tm) for six weeks' work. And they pay that because they know they have a government-granted monopoly allowing them to rake in money as a result of having BSotM's name on the poster.
If Hollywood movies starting making half as much money, then the 'stars' would no longer be worth as much and the cost of those movies would drop dramatically along with their salaries.
My #1 storage delay is waiting for virtual machines to suspend and resume.
Then you're not most people. Most people boot up the PC, do some web browsing and email, watch some youtube video their mate on myspacebook sent them and then shut down the PC. Booting faster is a benefit, but since that's largely random reads, a higher sequential read rate might save them a few seconds of boot time... they'd save a lot more by wiping Windows and installing Linux.
Most people don't bother with VM's, but suspend-to-disk in general is a feature that millions of home users should be using by default to save power (compared to never shutting down) and reduce waiting (compared to rebooting just to grab an email).
So again you're talking about something people might do once or twice a day being slightly faster because the sequential read and write time is faster. The rest of the time they'll see no benefit because PCs rarely perform hundreds of megabytes of sequential reads and writes in normal operation... for the kind of things most people do on their PC even the improved random reads and writes really only affect application startup and games which stream data from disk, it won't make web pages load noticeably faster or youtube videos play better.
Isn't it quieter? When I installed a SSD in my mythtv frontend, hard drive noise went from noticeable, to gone.
True, but my MythTV backend with two hard drives is still sitting beside the TV until I get around to moving it, and while I can hear drive noise close up, I can't hear it from the sofa.
You do realise that sequential reads and writes are pretty much irrelevant to most people, right? The big benefit of SSDs is _random_ read and write speed, which is where HDDs really suck.
For a lot of people, that would be the largest upgrade in terms of speed they could possibly give there computer. Maybe reducing the time to load photoshop from 8 seconds to 2.
And how often do you load photoshop? For most people, saving six seconds on something they do once a day is hardly going to be 'the largest upgrade in terms of speed they could possibly give their computer'.
I put an SSD in my new HTPC because I wanted it to boot up fast, and while it probably halves the boot time there it's otherwise pretty underwhelming.
I can easily believe that, but lengthened yellow lights also lead to more people trying to rush through on yellow.
Can you cite any proof of that? In my experience most people will stop for a yellow light if they can, so it won't suddenly make them run the light. Those who won't stop will have less chance of hitting someone because they're more likely to be through the light before it goes red.
Anyway, why not have lengthened yellow and traffic cams?
Because if you give people enough time to stop, the fines won't pay for the cameras.
Anyone paying attention and driving an appropriate speed for traffic conditions will be able to stop before the intersection for a red light -- assuming, of course, that the yellow light is of proper duration
Back in the real world, various cities have been shown to have reduced yellow light duration in order to increase fine revenues. It's hardly rocket science for a city that's low on cash. There were several newspaper articles about this in one city (DC, I think) a few years back.
And, back in the real world, the only method I'm aware of which has been proven to reduce collision at stop lights is to increase the duration of the yellow; red light cameras merely result in more rear-end collisions as people slam on the brakes to avoid a ticket. While you can argue that's better than being hit from the side as someone runs the light, if you actually want to reduce accidents rather than rake in the fines, it would be much better if cities just increased the duration of the yellow.
But SELinux is pain in the ass and generally disabled on every desktop oriented Linux distro like Ubuntu..
SELinux works fine in Redhat, at least to the extent that I've used it.
However, Ubuntu has Apparmor instead, and I believe they use it to wrap the PDF viewers by default. So even if this exploit works with some Linux PDF viewer it will probably not be allowed to execute arbitrary application files or modify arbitrary disk files on Ubuntu... making it far less effective.
The Zune had marketting and is a direct competitor.
But the Zune has also had decades of negative marketing through people's long experience of previous Microsoft products. It would have had to be really amazing to beat that.
The technical process of making people lose all sense of reality and simply consume whatever is most successful at telling them "buy me because I'm cool, and you can be too" is pretty straightforward to describe, but actually quite complicated to implement. It's called marketing.
Bingo. I used to work for a consumer electronics company, and there were three things we had to do in order to sell product.
1. Be on the shelf in the store. 2. Not totally suck. 3. Marketing, marketing and more marketing.
So long as the product was easily available and didn't suck so much that buyers would return it to the store, the only thing that really mattered was marketing... the more we money and effort we put into marketing, the more we sold.
Yeah, because a company that got and maintained its riches only because of its half-baked operating system and word processor is so much like a company that goes out on a limb (over and over again) to invent a new category of consumer device.
Wow! Apple invented the MP3 player, the cell phone and the tablet PC! You learn something new every day here on Slashdot!
Back in the real world, Apple produce moderately unsucky versions of consumer devices that have been in the market for years, and throw vast amounts of advertising at selling them. Right now they're actually managing to make Microsoft look only moderately evil.... at least Microsoft lets you run arbitrary software on Windows.
Of course there's nothing wrong with their business model so long as they're not holding a gun to your head and forcing you to buy one, but let's cut out the 'Apple is so innovative' crap which merely makes you look like another cultist.
You are confusing so many issues here that it's difficult to know how to reply. First, you are not using DNS to distribute your keys, so your experience is not particularly relevant.
How does using DNS to distribute keys tell me whether the connection is really, actually, physically encrypted?
You are also talking about using IPSec for a VPN, rather than for individual connections.
I'm talking about using it for individual connections between PCs..
Second, there is no reason why the TCP/IP stack could not expose a single function for getting the security state of the connection
Why should I trust the TCP stack's idea of whether the connection is secure when my web browser can determine that itself?
There is absolutely no point in using SSL over an end-to-end IPSEC connection.
Unless you actually want to ensure that your connection is actually, really secure, and the only way to do that is for your application to incorporate its own encryption and authentication. Rule #1 of security is to never trust what software outside your control tells you.
Other than performance or really, really badly implemented encryption schemes (e.g. two layers of ROT13), there is no downside to adding another layer of encryption.
Do we have any reason to think the CAs *have* been compromised? Not that I'm aware of.
The fact that someone's selling a box allowing MITM attacks with forged keys is a little bit suspicious... and since there are now so many CAs around the world it should be easy for governments to find one who'll happily sign a fake key for them, or set up trustuswerefromthegovernment.com as a new CA to sign any key they want.
End-to-end encryption should be done at the IP layer, not the TCP layer.
Sorry, but that's nonsense. Encryption should be done at the IP layer as well as by the application; if encryption is only done by IPSEC at a low level, then I have no way of knowing that my connection to my bank is secure, or is even going to the correct site.
To give an example, for a long time I've had my XP laptop at home configured to use IPSEC to talk to my Ubuntu server. Yesterday I discovered that at some point the Ubuntu server had stopped running the startup script that configures it to require IPSEC for connections from the laptop, so I've been connecting to it without encryption for an indeterminate amount of time; and the only way I found that out was because I ran wireshark.
IPSEC is a good idea, but it's definitely not a substitute for application-level encryption and authentication. It's also insanely difficult to configure and debug; I took about two days just to get a handful of PCs in my house talking to each other and even now I have to run a cron job on the Ubuntu server to ping the two Windows PCs every minute in order to ensure that IPSEC does get set up correctly once they're booted as initiating the connection from XP is very unreliable.
Just 'cause something has the potential to be abused you can't assume it will.
If a government has passed a law which can be abused and hasn't abused it, that just means they haven't got around to it yet.
For example, I remember when British anti-terrorist laws were only going to be used against, like, terrorists, and not Icelandic banks and people who over-fill their garbage bins. Or when speed cameras were only going to be installed at accident blackspots. And the 1920 Firearms Act was not going to be used to ban gun ownership, merely ensure that they would only be in the hands of decent law-abiding people.
In fact, it's hard to think of a British law which can be abused which hasn't been; I doubt that America is very different.
Overnight download requires no physical distribution at all.
Because everyone wants to wait until the next day every time they want to watch a movie.
And every time the network does become fast enough to watch that movie in real-time, the next standard comes along which makes it too slow; 4k images and 3D movies being the next two that the movie industry is likely to be pushing on consumers.
So, for the same resistance, the heat is proportional to the square of the current.
You must have some seriously lousy wires going to your hard drives if you're losing more power getting it from the PSU to the disk than you are in the actual drive.
Slashdot Mirror
I didn't know that. That was IMHO a bad move by AMD.
Yeah, I tend to agree, but they probably thought that removing them was a step forward (or needed the bits in the instruction for something else).
Why should a change of the page table be needed? All you need are separate segments for kernel and user mode.
For a start, because code segments no longer exist in x86_64.
Sorry, but if anything that simple can cause root access, then that’s a general error of the architecture and kernel.
By default you need root access (or an exploitable bug) to map page zero into your address space, and you need to specifically configure the kernel to allow it, and then you need an exploitable kernel bug to make use of it.
I wouldn't exactly call that 'simple'.
But if this gains you root access without you actually having it, it's a fault in the OS security. You cant rely on programming languages to protect against such methods.
Except you need root access in order to map page zero into your address space, and you generally need root access to configure the kernel so that it will allow root to map page zero into your address space (Wine in Ubuntu used to set the minimum mmap address to zero, I'm not sure whether it still does). So to get root access in this way you either need root access or multiple userspace vulnerabilities. And then you need a kernel flaw which executes code relative to a null pointer.
So while it's interesting and something developers should be aware of, it's not really a serious security threat in most cases; the last use of this exploit that I'm aware of required a kernel bug combined with a pulseaudio bug combined with an SELinux bug.
The Ice Storm is a very good movie.
Strange: I found it a mind-numbingly boring examination of evolution in action. And I normally like Ang Lee movies.
The real reason why Hollywood movies 'cost a truckload of money to make' is that they pay $200,000,000 to Big Star Of The Moment(tm) for six weeks' work. And they pay that because they know they have a government-granted monopoly allowing them to rake in money as a result of having BSotM's name on the poster.
If Hollywood movies starting making half as much money, then the 'stars' would no longer be worth as much and the cost of those movies would drop dramatically along with their salaries.
My #1 storage delay is waiting for virtual machines to suspend and resume.
Then you're not most people. Most people boot up the PC, do some web browsing and email, watch some youtube video their mate on myspacebook sent them and then shut down the PC. Booting faster is a benefit, but since that's largely random reads, a higher sequential read rate might save them a few seconds of boot time... they'd save a lot more by wiping Windows and installing Linux.
Most people don't bother with VM's, but suspend-to-disk in general is a feature that millions of home users should be using by default to save power (compared to never shutting down) and reduce waiting (compared to rebooting just to grab an email).
So again you're talking about something people might do once or twice a day being slightly faster because the sequential read and write time is faster. The rest of the time they'll see no benefit because PCs rarely perform hundreds of megabytes of sequential reads and writes in normal operation... for the kind of things most people do on their PC even the improved random reads and writes really only affect application startup and games which stream data from disk, it won't make web pages load noticeably faster or youtube videos play better.
Isn't it quieter? When I installed a SSD in my mythtv frontend, hard drive noise went from noticeable, to gone.
True, but my MythTV backend with two hard drives is still sitting beside the TV until I get around to moving it, and while I can hear drive noise close up, I can't hear it from the sofa.
32 GB / $125 USD / Sequential Write: 187.5 MB/s / Sequential Read: 294.5 MB/s.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820211419
You do realise that sequential reads and writes are pretty much irrelevant to most people, right? The big benefit of SSDs is _random_ read and write speed, which is where HDDs really suck.
For a lot of people, that would be the largest upgrade in terms of speed they could possibly give there computer. Maybe reducing the time to load photoshop from 8 seconds to 2.
And how often do you load photoshop? For most people, saving six seconds on something they do once a day is hardly going to be 'the largest upgrade in terms of speed they could possibly give their computer'.
I put an SSD in my new HTPC because I wanted it to boot up fast, and while it probably halves the boot time there it's otherwise pretty underwhelming.
I can easily believe that, but lengthened yellow lights also lead to more people trying to rush through on yellow.
Can you cite any proof of that? In my experience most people will stop for a yellow light if they can, so it won't suddenly make them run the light. Those who won't stop will have less chance of hitting someone because they're more likely to be through the light before it goes red.
Anyway, why not have lengthened yellow and traffic cams?
Because if you give people enough time to stop, the fines won't pay for the cameras.
Anyone paying attention and driving an appropriate speed for traffic conditions will be able to stop before the intersection for a red light -- assuming, of course, that the yellow light is of proper duration
Back in the real world, various cities have been shown to have reduced yellow light duration in order to increase fine revenues. It's hardly rocket science for a city that's low on cash. There were several newspaper articles about this in one city (DC, I think) a few years back.
And, back in the real world, the only method I'm aware of which has been proven to reduce collision at stop lights is to increase the duration of the yellow; red light cameras merely result in more rear-end collisions as people slam on the brakes to avoid a ticket. While you can argue that's better than being hit from the side as someone runs the light, if you actually want to reduce accidents rather than rake in the fines, it would be much better if cities just increased the duration of the yellow.
Sounds very similar to the security level capabilities in OpenSolaris too.
But SELinux is pain in the ass and generally disabled on every desktop oriented Linux distro like Ubuntu..
SELinux works fine in Redhat, at least to the extent that I've used it.
However, Ubuntu has Apparmor instead, and I believe they use it to wrap the PDF viewers by default. So even if this exploit works with some Linux PDF viewer it will probably not be allowed to execute arbitrary application files or modify arbitrary disk files on Ubuntu... making it far less effective.
The Zune had marketting and is a direct competitor.
But the Zune has also had decades of negative marketing through people's long experience of previous Microsoft products. It would have had to be really amazing to beat that.
The technical process of making people lose all sense of reality and simply consume whatever is most successful at telling them "buy me because I'm cool, and you can be too" is pretty straightforward to describe, but actually quite complicated to implement. It's called marketing.
Bingo. I used to work for a consumer electronics company, and there were three things we had to do in order to sell product.
1. Be on the shelf in the store.
2. Not totally suck.
3. Marketing, marketing and more marketing.
So long as the product was easily available and didn't suck so much that buyers would return it to the store, the only thing that really mattered was marketing... the more we money and effort we put into marketing, the more we sold.
Yeah, because a company that got and maintained its riches only because of its half-baked operating system and word processor is so much like a company that goes out on a limb (over and over again) to invent a new category of consumer device.
Wow! Apple invented the MP3 player, the cell phone and the tablet PC! You learn something new every day here on Slashdot!
Back in the real world, Apple produce moderately unsucky versions of consumer devices that have been in the market for years, and throw vast amounts of advertising at selling them. Right now they're actually managing to make Microsoft look only moderately evil.... at least Microsoft lets you run arbitrary software on Windows.
Of course there's nothing wrong with their business model so long as they're not holding a gun to your head and forcing you to buy one, but let's cut out the 'Apple is so innovative' crap which merely makes you look like another cultist.
Eurpoe doesn't have nearly as much leverage as the US, but Canada is looking to diversify trading partners...
Europe needs resources far more than Canada needs Europe.
You are confusing so many issues here that it's difficult to know how to reply. First, you are not using DNS to distribute your keys, so your experience is not particularly relevant.
How does using DNS to distribute keys tell me whether the connection is really, actually, physically encrypted?
You are also talking about using IPSec for a VPN, rather than for individual connections.
I'm talking about using it for individual connections between PCs..
Second, there is no reason why the TCP/IP stack could not expose a single function for getting the security state of the connection
Why should I trust the TCP stack's idea of whether the connection is secure when my web browser can determine that itself?
There is absolutely no point in using SSL over an end-to-end IPSEC connection.
Unless you actually want to ensure that your connection is actually, really secure, and the only way to do that is for your application to incorporate its own encryption and authentication. Rule #1 of security is to never trust what software outside your control tells you.
Other than performance or really, really badly implemented encryption schemes (e.g. two layers of ROT13), there is no downside to adding another layer of encryption.
Do we have any reason to think the CAs *have* been compromised? Not that I'm aware of.
The fact that someone's selling a box allowing MITM attacks with forged keys is a little bit suspicious... and since there are now so many CAs around the world it should be easy for governments to find one who'll happily sign a fake key for them, or set up trustuswerefromthegovernment.com as a new CA to sign any key they want.
End-to-end encryption should be done at the IP layer, not the TCP layer.
Sorry, but that's nonsense. Encryption should be done at the IP layer as well as by the application; if encryption is only done by IPSEC at a low level, then I have no way of knowing that my connection to my bank is secure, or is even going to the correct site.
To give an example, for a long time I've had my XP laptop at home configured to use IPSEC to talk to my Ubuntu server. Yesterday I discovered that at some point the Ubuntu server had stopped running the startup script that configures it to require IPSEC for connections from the laptop, so I've been connecting to it without encryption for an indeterminate amount of time; and the only way I found that out was because I ran wireshark.
IPSEC is a good idea, but it's definitely not a substitute for application-level encryption and authentication. It's also insanely difficult to configure and debug; I took about two days just to get a handful of PCs in my house talking to each other and even now I have to run a cron job on the Ubuntu server to ping the two Windows PCs every minute in order to ensure that IPSEC does get set up correctly once they're booted as initiating the connection from XP is very unreliable.
Just 'cause something has the potential to be abused you can't assume it will.
If a government has passed a law which can be abused and hasn't abused it, that just means they haven't got around to it yet.
For example, I remember when British anti-terrorist laws were only going to be used against, like, terrorists, and not Icelandic banks and people who over-fill their garbage bins. Or when speed cameras were only going to be installed at accident blackspots. And the 1920 Firearms Act was not going to be used to ban gun ownership, merely ensure that they would only be in the hands of decent law-abiding people.
In fact, it's hard to think of a British law which can be abused which hasn't been; I doubt that America is very different.
Overnight download requires no physical distribution at all.
Because everyone wants to wait until the next day every time they want to watch a movie.
And every time the network does become fast enough to watch that movie in real-time, the next standard comes along which makes it too slow; 4k images and 3D movies being the next two that the movie industry is likely to be pushing on consumers.
P=I^2 R
So, for the same resistance, the heat is proportional to the square of the current.
You must have some seriously lousy wires going to your hard drives if you're losing more power getting it from the PSU to the disk than you are in the actual drive.
I had a 2 meg RAM drive back in the 80s.
I had a 128MB RAM drive back in the early 90s; cost the company about $50,000 if I remember correctly. But boy did Windows 3.x start up fast.
Firmware updates, performance refresh utilities, partition alignment... With HDDs you didn't have to worry about any of this.
I take it you've never bought an HDD with 4k sectors?
I have. I still have a hard drive from 1992, running on a 486/33, running an old Redhat distro.
Good point, in 2007 I was copying files off my 1995 laptop drive before I threw it out; though I did lose a few files due to bad sectors.