Re: [PATCH v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Thomas Garnier
On Mon, Aug 8, 2016 at 10:16 PM, Mika Penttilä wrote: > On 08/08/2016 09:40 PM, 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

Re: [PATCH v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-09 Thread Thomas Garnier
On Mon, Aug 8, 2016 at 10:16 PM, Mika Penttilä wrote: > On 08/08/2016 09:40 PM, 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

Re: [PATCH v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 Thread Mika Penttilä
On 08/08/2016 09:40 PM, 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 randomization and

Re: [PATCH v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 Thread Mika Penttilä
On 08/08/2016 09:40 PM, 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 randomization and

Re: [PATCH v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 Thread H. Peter Anvin
On August 8, 2016 9:01:42 PM PDT, Borislav Petkov wrote: >On Mon, Aug 08, 2016 at 11:40:07AM -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 v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 Thread H. Peter Anvin
On August 8, 2016 9:01:42 PM PDT, Borislav Petkov wrote: >On Mon, Aug 08, 2016 at 11:40:07AM -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 v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 Thread Borislav Petkov
On Mon, Aug 08, 2016 at 11:40:07AM -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 v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 Thread Borislav Petkov
On Mon, Aug 08, 2016 at 11:40:07AM -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 v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 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 v1 2/2] x86/KASLR: Increase BRK pages for KASLR memory randomization

2016-08-08 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