Re: The address displayed by ldd

From: Kevin Puetz
Date: Sat Mar 12 2005 - 19:21:50 EST


It's the load address of the library, and it's basically not meant to be a
stable value. It will at least depend on the load order and size of the
libraries, and it may in fact be intentionally randomized each run as a
security measure against ret2libc type attacks (PaX, execshield, etc all do
this, as does prelink everytime it re-prelinks libraries). It's entirely
plausible for it to change from run to run, much less machine to machine.

gan_xiao_jun@xxxxxxxxx wrote:

> Hi,
>
> I have a small question,
> I am not sure if it belongs to kernel.
> I often use ldd to find librarys needed.
> In some systems,the address display by ldd not
> changes,
> But in other systems, it changes.
>
> What is the reason of the difference?
> Is it cause by some setting in kernel?
>
> Thanks in advance.
> gan
>
>
>
>
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