Kernel hacking option "Debug memory allocations" possible leak of PaX memory randomization

Hi,

I've compiled a new kernel (2.6.7) 2 days ago, using the grSecurity patch that comes with PaX inside.

I've configured the environment for running with PaX, and i ran out that PaX tests.

They shown suspicious results:

Anonymous mapping randomisation test     : 16 bits (guessed)
Heap randomisation test (ET_EXEC)        : 13 bits (guessed)
Heap randomisation test (ET_DYN)         : 23 bits (guessed)
Main executable randomisation (ET_EXEC)  : No randomisation
Main executable randomisation (ET_DYN)   : 15 bits (guessed)
Shared library randomisation test        : 15 bits (guessed)
Stack randomisation test (SEGMEXEC)      : 23 bits (guessed)
Stack randomisation test (PAGEEXEC)      : 23 bits (guessed)

I didn't know why the test shown that but i'm suspecting on the kernel hacking option called "Debug memory allocations" that it's enabled on my kernel configuration.

I've talked with Peter Busser from the Adamantix project about it he thinks that it's possible, i'm not sure and i didn't make a further research on it.

Is anyone of you having the same situation, is it an unexpected behavior or it's a bug on the kernel source?
Is that option non-compatible with PaX RANDSTACK and the rest of PaX's memory randomization features?

Cheers,

Lorenzo Hernandez Garcia-Hierro <[email protected]>

On Tuesday 13 July 2004 15:51, Lorenzo Hernandez Garcia-Hierro wrote:

Hi Lorenzo,

CC pageexec at freemail dot hu - He's the PaX programmer.

ciao, Marc

Hi Marc,

OK, thanks, i forget the K of RANDKSTACK, sorry.

Cheers,

Lorenzo Hernandez Garcia-Hierro <[email protected]>