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no, the rcscripts must now parse the kernel commandline opts |
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to get a few options. There's really not many other ways to |
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do it. Besides you just proved by your statement that someone |
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could instead pass init=/bin/sh and override any sort of |
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init process, so trying to make the 'cdroot' option secure |
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is obsurd, as there's 10 million other ways to get in if you |
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have direct access to the computer. |
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|
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-Brad |
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|
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> I think what paul means is that when a bootloader isn't password |
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> protected, a malign user could pass 'cdroot' to the kernel and exploit |
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> some of the things this triggers in the rc scripts (autologin?) if |
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> those scripts directly parse the arguments passed to the kernel. |
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> |
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> The style of exploit is quite similar to passing: |
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> |
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> init=/home/hacker/exploit.sh or init=/bin/sh |
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> |
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> to the kernel on a system one has direct access to and whose bootloader |
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> isn't pass-protected. This issue is relevant for computers from |
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> computer rooms used for teaching/exams... |
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> |
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> But if I'm not mistaken the rc-scripts themselves do not 'parse kernel |
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> output', it's the linuxrc which parses the kernel arguments , and |
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> exports cdboot to the env, right? So there should be no security issues |
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> for systems which don't have an initrd and thus no linuxrc. |
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> |
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> Pieter |
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> |
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> On 17 Jan 2004, at 17:28, Brad House wrote: |
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> |
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>> don't have a clue what you mean by this statement |
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>> It is only applicable if you pass cdroot to your kernel. |
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>> If you're using a genkernel compiled kernel, that will |
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>> cause your system to not boot unless you're booting off a |
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>> cd. And for advanced users who actually build their own |
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>> kernel, I think they'd be brighter than to try to do autologin |
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>> stuff by passing cdroot to the kernel. |
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>> |
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>> Sorry, linux is not idiot-proof. This is a NON-ISSUE. |
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>> |
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>> -Brad |
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>> |
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>> |
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>>> Will there be a way to keep these of of hd installs. I don't think |
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>>> that |
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>>> this |
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>>> kind of functionality is good on hd installs. It makes it too easy to |
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>>> create |
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>>> an insecure system |
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>> |
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>> |
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>> -- |
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>> gentoo-releng@g.o mailing list |
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>> |
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> |
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> |
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> -- |
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> gentoo-releng@g.o mailing list |
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> |
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> |
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> |
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|
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|
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-- |
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