Re: Chroot bug

From: Miloslav Semler
Date: Tue Sep 25 2007 - 11:50:50 EST

Adrian Bunk napsal(a):
On Wed, Sep 26, 2007 at 12:40:27AM +0930, David Newall wrote:

Miloslav Semler pointed out that a root process can chdir("..") out of its chroot. Although this is documented in the man page, it conflicts with the essential function, which is to change the root directory of the process. In addition to any creative uses, for example Philipp Marek's loading dynamic libraries, it seems clear that the prime purpose of chroot is to aid security. Being able to cd your way out is handy for the bad guys, but the good guys don't need it; there are a thousand better, safer solutions.

The bad guys most likely also now other tricks to escape the chroot.

If you are root in the chroot you can e.g. mount the partition with the root filesystem inside the chroot.

If a bad guy becomes root inside a chroot it's game over.
but why there keep 1000001th. It is same as:
There is milion ways howto dos your system.. Then we needn't repair bugs...

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