Re: [PATCH v2 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Thomas Garnier
On Tue, Aug 9, 2016 at 9:54 AM, Borislav Petkov wrote: > On Tue, Aug 09, 2016 at 09:35:54AM -0700, Thomas Garnier wrote: >> Default implementation expects 6 pages maximum are needed for low page >> allocations. If KASLR memory randomization is enabled, the worse case >> of e820

Re: [PATCH v2 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Thomas Garnier
On Tue, Aug 9, 2016 at 9:54 AM, Borislav Petkov wrote: > On Tue, Aug 09, 2016 at 09:35:54AM -0700, Thomas Garnier wrote: >> Default implementation expects 6 pages maximum are needed for low page >> allocations. If KASLR memory randomization is enabled, the worse case >> of e820 layout would

Re: [PATCH v2 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Borislav Petkov
On Tue, Aug 09, 2016 at 09:35:54AM -0700, Thomas Garnier wrote: > Default implementation expects 6 pages maximum are needed for low page > allocations. If KASLR memory randomization is enabled, the worse case > of e820 layout would require 12 pages (no large pages). It is due to the > PUD level

Re: [PATCH v2 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Borislav Petkov
On Tue, Aug 09, 2016 at 09:35:54AM -0700, Thomas Garnier wrote: > Default implementation expects 6 pages maximum are needed for low page > allocations. If KASLR memory randomization is enabled, the worse case > of e820 layout would require 12 pages (no large pages). It is due to the > PUD level

[PATCH v2 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Thomas Garnier
Default implementation expects 6 pages maximum are needed for low page allocations. If KASLR memory randomization is enabled, the worse case of e820 layout would require 12 pages (no large pages). It is due to the PUD level randomization and the variable e820 memory layout. This bug was found

[PATCH v2 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Thomas Garnier
Default implementation expects 6 pages maximum are needed for low page allocations. If KASLR memory randomization is enabled, the worse case of e820 layout would require 12 pages (no large pages). It is due to the PUD level randomization and the variable e820 memory layout. This bug was found