Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-25 Thread Mark Rutland
On Fri, Jul 26, 2019 at 01:14:26AM +1000, Daniel Axtens wrote: > Mark Rutland writes: > > On Thu, Jul 25, 2019 at 09:53:08AM +0200, Dmitry Vyukov wrote: > >> FTR, Daniel just mailed: > >> > >> [PATCH 0/3] kasan: support backing vmalloc space with real shadow memory > >> https://groups.google.com/

Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-25 Thread Daniel Axtens
Mark Rutland writes: > On Thu, Jul 25, 2019 at 09:53:08AM +0200, Dmitry Vyukov wrote: >> On Wed, Jul 24, 2019 at 1:21 PM Mark Rutland wrote: >> > >> > On Wed, Jul 24, 2019 at 11:11:49AM +0200, Dmitry Vyukov wrote: >> > > On Tue, Jul 23, 2019 at 6:41 PM Mark Rutland >> > > wrote: >> > > > >> >

Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-25 Thread Mark Rutland
On Thu, Jul 25, 2019 at 09:53:08AM +0200, Dmitry Vyukov wrote: > On Wed, Jul 24, 2019 at 1:21 PM Mark Rutland wrote: > > > > On Wed, Jul 24, 2019 at 11:11:49AM +0200, Dmitry Vyukov wrote: > > > On Tue, Jul 23, 2019 at 6:41 PM Mark Rutland wrote: > > > > > > > > On Fri, Jul 19, 2019 at 03:28:17PM

Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-25 Thread Dmitry Vyukov
On Wed, Jul 24, 2019 at 1:21 PM Mark Rutland wrote: > > On Wed, Jul 24, 2019 at 11:11:49AM +0200, Dmitry Vyukov wrote: > > On Tue, Jul 23, 2019 at 6:41 PM Mark Rutland wrote: > > > > > > On Fri, Jul 19, 2019 at 03:28:17PM +0200, Marco Elver wrote: > > > > Enabling STACK_GUARD_PAGE helps catching

Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-24 Thread Mark Rutland
On Wed, Jul 24, 2019 at 11:11:49AM +0200, Dmitry Vyukov wrote: > On Tue, Jul 23, 2019 at 6:41 PM Mark Rutland wrote: > > > > On Fri, Jul 19, 2019 at 03:28:17PM +0200, Marco Elver wrote: > > > Enabling STACK_GUARD_PAGE helps catching kernel stack overflows > > > immediately > > > rather than causi

Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-24 Thread Dmitry Vyukov
On Tue, Jul 23, 2019 at 6:41 PM Mark Rutland wrote: > > On Fri, Jul 19, 2019 at 03:28:17PM +0200, Marco Elver wrote: > > Enabling STACK_GUARD_PAGE helps catching kernel stack overflows immediately > > rather than causing difficult-to-diagnose corruption. Note that, unlike > > virtually-mapped kern

Re: [PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-23 Thread Mark Rutland
On Fri, Jul 19, 2019 at 03:28:17PM +0200, Marco Elver wrote: > Enabling STACK_GUARD_PAGE helps catching kernel stack overflows immediately > rather than causing difficult-to-diagnose corruption. Note that, unlike > virtually-mapped kernel stacks, this will effectively waste an entire page of > memo

[PATCH 1/2] kernel/fork: Add support for stack-end guard page

2019-07-19 Thread Marco Elver
Enabling STACK_GUARD_PAGE helps catching kernel stack overflows immediately rather than causing difficult-to-diagnose corruption. Note that, unlike virtually-mapped kernel stacks, this will effectively waste an entire page of memory; however, this feature may provide extra protection in cases that