Re: [PATCH 2/2] ASLR: add possibility for more fine-grained tweaking

[Geert Uytterhoeven]

On Wed, 6 Feb 2008, Ingo Molnar wrote:
> @@ -541,6 +541,18 @@ config ELF_CORE
>  	help
>  	  Enable support for generating core dumps. Disabling saves about 4k.
>  
> +config COMPAT_BRK
> +	bool "Disable heap randomization"
> +	default y
> +	help
> +	  Randomizing heap placement makes heap exploits harder, but it
> +	  also breaks ancient binaries (including anything libc5 based).
> +	  This option changes the bootup default to heap randomization
> +	  disabled, and can be overriden runtime by setting
> +	  /proc/sys/kernel/randomize_va_space to 2.
> +
> +	  On non-ancient distros (post-2000 ones) Y is usually a safe choice.

Somehow my belly feeling tells me something is wrong with this description...

Ah, a negative option (Y -> disable).  So Y is always safe.

`non-ancient distros' really means `recent distros', and if you have one,
then _N_ should be a safe choice, too?

With kind regards,

Geert Uytterhoeven
Software Architect

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