Messages in this thread | | | Date | Wed, 29 Apr 2015 16:56:54 +0200 (CEST) | From | Jiri Kosina <> | Subject | Re: [PATCH 2/2] livepatch: x86: make kASLR logic more accurate |
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On Tue, 28 Apr 2015, Josh Poimboeuf wrote:
> On Mon, Apr 27, 2015 at 04:28:58PM +0200, Jiri Kosina wrote: > > We give up old_addr hint from the coming patch module in cases when kernel > > load base has been randomized (as in such case, the coming module has no > > idea about the exact randomization offset). > > > > We are currently too pessimistic, and give up immediately as soon as > > CONFIG_RANDOMIZE_BASE is set; this doesn't however directly imply that the > > load base has actually been randomized. There are config options that > > disable kASLR (such as hibernation), user could have disabled kaslr on > > kernel command-line, etc. > > > > The loader propagates the information whether kernel has been randomized > > through bootparams. This allows us to have the condition more accurate. > > > > On top of that, it seems unnecessary to give up old_addr hints even if > > randomization is active. The relocation offset can be computed using > > kaslr_ofsset(), and therefore old_addr can be adjusted accordingly. > > > > Signed-off-by: Jiri Kosina <jkosina@suse.cz> > > Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Applied to for-4.2/kaslr.
Thanks,
-- Jiri Kosina SUSE Labs
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