Re: [PATCH 1/3] vmalloc: Add __vmalloc_node_try_addr function

[Randy Dunlap]

On 06/20/2018 03:35 PM, Kees Cook wrote:
> On Wed, Jun 20, 2018 at 3:16 PM, Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
>> On 06/20/2018 03:09 PM, Rick Edgecombe wrote:
>>> +void *__vmalloc_node_try_addr(unsigned long addr, unsigned long size,
>>> +                     gfp_t gfp_mask, pgprot_t prot, unsigned long vm_flags,
>>> +                     int node, const void *caller)
>>> +{
>>
>> so this isn't optional, eh?  You are going to force it on people because?
> 
> RANDOMIZE_BASE isn't optional either. :) This improves the module
> address entropy with (what seems to be) no down-side, so yeah, I think
> it should be non-optional. :)

In what kernel tree is RANDOMIZE_BASE not optional?

x86:
config RANDOMIZE_BASE
	bool "Randomize the address of the kernel image (KASLR)"
	depends on RELOCATABLE
	default y

mips:
config RANDOMIZE_BASE
	bool "Randomize the address of the kernel image"
	depends on RELOCATABLE

arm64:
config RANDOMIZE_BASE
	bool "Randomize the address of the kernel image"
	select ARM64_MODULE_PLTS if MODULES
	select RELOCATABLE


thanks,
-- 
~Randy