Messages in this thread | | | Date | Thu, 26 May 2011 16:31:08 -0400 | From | Vivek Goyal <> | Subject | Re: [RFC][PATCH] Randomize kernel base address on boot |
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On Thu, May 26, 2011 at 04:16:05PM -0400, Valdis.Kletnieks@vt.edu wrote: > On Thu, 26 May 2011 16:01:21 EDT, Vivek Goyal said: > > > Also randomization of kernel load address at run time will probably have > > some issues with crashkernel=X@Y address syntax. So far user knew what > > address first kernel is booting from and user could speicy where to > > reserve memory. Now it might happen that user specified some memory > > to reserve and kernel decided to occupy that space resulting in failed > > memory reservation for crash kernel. > > That is however fixable - the randomizer just needs to make sure it doesn't > overlay the crashkernel= space, and the crashkernel needs to be started with a > 'norandomize' parameter.
That can be done but at the same time if kernel does not find any suitable range to boot from, it should override crashkernel=X@Y settings and fail crash memory reservation.
I guess with randomize space thing a more suitable crash kernel command line will be crashkernel=X where kernel decides the base address for second kernel depending on availability.
> If your threat model includes attacks on the > crashkernel that randomizing will help with, you got bigger problems. ;) >
:-) I think norandomize for kdump kernel should be just fine.
Thanks Vivek
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