How secure is a WUBI Kubuntu installation?

[PhilT]

A friend has purchased a new Acer Aspire All-in-One which came with M$7 installed.

She is anxious to try Kubuntu but also anxious not to void the new machine's guarantee by mucking about with disc partitions, initially at least!

So, I've helped her by removing all the proprietry "Crap", Pop-ups, and redundant junk, and installing MSE etc.etc. and then I've installed Kubuntu 11.10 for her via Wubi.

All went well, the re-boot gave the 2 boot options : Win7 or Kubuntu as expected. Kubuntu loaded first time, updated etc. and appears to be kosher.

The question is this ; Because Kubuntu loads a linux kernel and her system sits behind a router, is it as secure as a "simple" Kubuntu box? Or does the presence of the M$ files still provide dangers even though Win7 is not running. The Kubuntu system is "installed" on the M$ C:\ drive as any othe "program" would be and presumably uses the NTFS file structure (I haven't investigated). Hopefully this is only a temporary situation, but security is paramount!

[claydoh]

Re: Re: How secure is a WUBI Kubuntu installation?

Add far as i recall, outside of the windows boot loader, you are running Kubuntu only and no windows stuff loads. WUBI allows you to run *buntu from within windows file system , it is quite similar to running it from a flash drive with a "persistence" file, only it is a big file on your drive.

Kinda sorta

You should be as safe as if you were running it natively.

Sent from my Android phone using Tapatalk

[GreyGeek]

Re: How secure is a WUBI Kubuntu installation?

Windows IS NOT running when the WUBI installation of Linux IS running. It's as if Linux is the sole OS on the machine.

However, the WUBI uses Windows boot menu. When I installed WUBI on my wife's Acer Aspire One AD0521 it was falling off a log easy and ran like a charm. But, when the first KERNAL update came along, adding the new kernel borked the boot menu and I could access only Windows. The SuperGrub CD fixed things but my advice is to PIN the Linux kernel & headers to they don't update.

Pin linux-generic at current version

To tell apt-get to leave the linux kernel untouched when it upgrades the system, we will pin the package linux-generic to the current version. First, find the version:

$ apt-cache policy linux-generic
linux-generic:
Installed: 2.6.28.11.15
Candidate: 2.6.28.19.24
Version table:
2.6.28.19.24 0
500 http://us.archive.ubuntu.com jaunty-updates/restricted Packages
500 http://security.ubuntu.com jaunty-security/restricted Packages
*** 2.6.28.11.15 0
500 http://us.archive.ubuntu.com jaunty/restricted Packages
100 /var/lib/dpkg/status

To pin this version we need to create a file called "linux-generic" in the edit /etc/apt/preferences.d (as root) directory and add the following lines:

Package: linux-generic
Pin: version 2.6.28.11*
Priority: 1001

That will stop the Konsole use of "apt-get" from installing a new kernel, and block the package managers as well.

[PhilT]

Re: How secure is a WUBI Kubuntu installation?

Thanks to you both for your helpful comments! I am very grateful.

GG: your additional suggestions about the kernel fixing are most welcome! I'll "fix" for her until she takes the plunge and puts Kubuntu on permanently -- or I suppose I could use Gparted to shrink/move the pre-installed partitions and then dual-boot with Kubuntu leaving the native Win7 to its shrunken demise? INterestingly this ACER system has sensibly got two partitions a C:\ drive with programs and a D:\ drive for data. Wubi installed on the C:\ drive.

One question I raised: in the curreent Wubi-environment is KUbuntu running on the NTFS file system? I suppose it must be. And presumably all the other hardware is still accessible? It has INtel graphics on board and I wondered about using Steve Riley's suggestions regarding installing the xorg-edgers X-server, Mesa and INtel drivers.

[GreyGeek]

Re: How secure is a WUBI Kubuntu installation?

Thanks to you both for your helpful comments! I am very grateful.

GG: your additional suggestions about the kernel fixing are most welcome! I'll "fix" for her until she takes the plunge and puts Kubuntu on permanently -- or I suppose I could use Gparted to shrink/move the pre-installed partitions and then dual-boot with Kubuntu leaving the native Win7 to its shrunken demise? INterestingly this ACER system has sensibly got two partitions a C:\ drive with programs and a D:\ drive for data. Wubi installed on the C:\ drive.

Are you sure the D:\ is for user data? Did you create it from a partition? IIRC, the D:\ drive was where the image of Windows was put and from which the recovery took place when needed. Later they made it a "phantom" partition. But, I'd check to be sure.

Win7 has a partition shrinker. I would use it to peal off at least 30GB of HD (the more the merrier, but I wouldn't take more than have half the remaining space so Win7 won't have problems running. The less space you leave it the slower the NTFS will run. My daughter's XP laptop filled up and had, IIRC, less than 50MB of freespace. It began taking as long as 30 minutes to boot to a working desktop and would run slower than a snail. I cleaned it up and gave her about 1.5GB of free space and got her boot time down to about 3 minutes.

One question I raised: in the curreent Wubi-environment is KUbuntu running on the NTFS file system? I suppose it must be. And presumably all the other hardware is still accessible?

In the WUBI environment Kubuntu is a file on the NTFS system which is run during bootup after being called by the Windows boot menu, which only temporarily occupies memory until it hands the system off to Linux. The size of the file is the amount of "HD space" Kubuntu appears to have when you show root size with Dolphin. The HD is spinning, but the NTFS is not running, EXT4 is. Windows isn't even in RAM. Nothing of Windows is running. Linux fills the RAM and accesses and controls the hardware. It does NOT go through Windows to access the hardware. It is NOT like a guest OS in VirutalBox, where the host OS is running in the background. Linux has the ability to read and write to the NFTS system, so you can read and write to the Windows part of the HD, but I would generally avoid that.

It has INtel graphics on board ... I wondered about using Steve Riley's suggestions regarding installing the xorg-edgers X-server, Mesa and INtel drivers.

It's an easy install or removal using the add-app-repository command on its PPA, if you have installed that command. It is not yet in the Kubuntu 12.04 repository. It is in the python-software-properties package and is probably already on your system.

[SteveRiley]

Re: How secure is a WUBI Kubuntu installation?

Win7 has a partition shrinker. I would use it to peal off at least 30GB of HD (the more the merrier, but I wouldn't take more than have the remaining space so Win7 won't have problems running.

It's always good to defrag before you change the size of a partition; this operation moves all the files to the partition's front, thus exposing more free space from which to carve a separate partition. However, your Windows system likely has two files that can't be moved: pagefile.sys and hiberfil.sys. You can remove these, and this obtain a better fragmentation, by temporarily disabling the page file and hibernation. You can perform these tasks at an elevated command prompt.

Disable and remove the page file
wmic computersystem where name="%computername%" set AutomaticManagedPagefile=False
wmic pagefileset where name="C:\\pagefile.sys" delete

Disable and remove the hibernation file
powercfg /hibernate off

Reboot. Modify your partitions as you like. Reboot. Then, at an elevated command prompt:

Enable the page file
wmic pagefileset create name="C:\pagefile.sys"
wmic computersystem where name="%computername%" set AutomaticManagedPagefile=True

Enable hibernation
powercfg /hibernate on

And finally, reboot.

[GreyGeek]

Re: How secure is a WUBI Kubuntu installation?

There you go, PhilT, direct from the WinMaster!

It was a good tip for me, too. I didn't know one could remove pagefile.sys and hiberfil.sys to let defrag do a better job. I rarely took more than half the HD for Linux, but a lot of times there was an "unmovable" file blocking the desire to take more. I am assuming that during the next boot of Windows it will recreate those two files, right WinMaster?

[SteveRiley]

Re: How secure is a WUBI Kubuntu installation?

WinMaster!

Why do I have the sinking feeling that this nickname is going to stick? :P

I am assuming that during the next boot of Windows it will recreate those two files, right WinMaster?

The only way to make the pagefile and hibernation file go away is to disable the functionality. There's no temporary setting for that; the disabling commands survive reboots. That's why I provided the commands to re-enable the functionality after you finish the defrag and shrink process.

[PhilT]

Re: How secure is a WUBI Kubuntu installation?

Well, thank you both, for that priceless information.
I've just woken up to get that info this morning (live in UK) so will try the suggestions for her later!
Her Acer machine has a 1Tb disc - so no problem with space with so much real estate
GG - thanks for the NTFS / ext4 heads up.
WinMaster - thanks for that info about defragging. I used Piriform's defragger already (after cleaning up with CCleaner) but will repeat as per your suggestions!

[GreyGeek]

Re: How secure is a WUBI Kubuntu installation?

.....
Why do I have the sinking feeling that this nickname is going to stick? :P

I'm sorry. Hey everybody, FORGET "WinMaster".
At least you don't turn your head to look like I do when I hear the phrase "Hey, stupid!"

I am assuming that during the next boot of Windows it will recreate those two files, right WinMaster?

The only way to make the pagefile and hibernation file go away is to disable the functionality. There's no temporary setting for that; the disabling commands survive reboots. That's why I provided the commands to re-enable the functionality after you finish the defrag and shrink process.

mmm.... I assumed too much. But, I am learning more stuff from your posts about Windows and how it operates than I ever knew or thought I knew. The tidbits in this thread are going to save a LOT of Linux users a LOT of pain and suffering from mishandling Windows trying to set it up to dual boot.

[PhilT]

Re: How secure is a WUBI Kubuntu installation?

+1