Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Eric W. Biederman
Kees Cook writes: > On Wed, Dec 11, 2013 at 3:15 PM, Eric W. Biederman > wrote: >> Kees Cook writes: >> >>> On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman >>> wrote: Kees Cook writes: > For general-purpose (i.e. distro) kernel builds it makes sense to build > with

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Kees Cook
On Wed, Dec 11, 2013 at 3:15 PM, Eric W. Biederman wrote: > Kees Cook writes: > >> On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman >> wrote: >>> Kees Cook writes: >>> For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Eric W. Biederman
Kees Cook writes: > On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman > wrote: >> Kees Cook writes: >> >>> For general-purpose (i.e. distro) kernel builds it makes sense to build with >>> CONFIG_KEXEC to allow end users to choose what kind of things they want to >>> do >>> with kexec.

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Kees Cook
On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman wrote: > Kees Cook writes: > >> For general-purpose (i.e. distro) kernel builds it makes sense to build with >> CONFIG_KEXEC to allow end users to choose what kind of things they want to do >> with kexec. However, in the face of trying to lock

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Eric W. Biederman
Kees Cook writes: > For general-purpose (i.e. distro) kernel builds it makes sense to build with > CONFIG_KEXEC to allow end users to choose what kind of things they want to do > with kexec. However, in the face of trying to lock down a system with such > a kernel, there needs to be a way to

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Eric W. Biederman
Kees Cook keesc...@chromium.org writes: For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec. However, in the face of trying to lock down a system with such a kernel, there needs

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Kees Cook
On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman ebied...@xmission.com wrote: Kees Cook keesc...@chromium.org writes: For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec.

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Eric W. Biederman
Kees Cook keesc...@chromium.org writes: On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman ebied...@xmission.com wrote: Kees Cook keesc...@chromium.org writes: For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Kees Cook
On Wed, Dec 11, 2013 at 3:15 PM, Eric W. Biederman ebied...@xmission.com wrote: Kees Cook keesc...@chromium.org writes: On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman ebied...@xmission.com wrote: Kees Cook keesc...@chromium.org writes: For general-purpose (i.e. distro) kernel builds it

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-11 Thread Eric W. Biederman
Kees Cook keesc...@chromium.org writes: On Wed, Dec 11, 2013 at 3:15 PM, Eric W. Biederman ebied...@xmission.com wrote: Kees Cook keesc...@chromium.org writes: On Wed, Dec 11, 2013 at 9:52 AM, Eric W. Biederman ebied...@xmission.com wrote: Kees Cook keesc...@chromium.org writes: For

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Kees Cook
On Tue, Dec 10, 2013 at 11:14 AM, Vivek Goyal wrote: > On Tue, Dec 10, 2013 at 10:54:00AM -0800, H. Peter Anvin wrote: >> On 12/10/2013 10:33 AM, Vivek Goyal wrote: >> > On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: >> >> Of course it isn't. >> > >> > I am not sure what are you

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Tue, Dec 10, 2013 at 10:54:00AM -0800, H. Peter Anvin wrote: > On 12/10/2013 10:33 AM, Vivek Goyal wrote: > > On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: > >> Of course it isn't. > > > > I am not sure what are you trying to say. This is too brief. > > > > Thanks > > Vivek

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread H. Peter Anvin
On 12/10/2013 10:33 AM, Vivek Goyal wrote: > On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: >> Of course it isn't. > > I am not sure what are you trying to say. This is too brief. > > Thanks > Vivek > Of course it is not sufficient. Once you can get arbitrary code into kernel

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: > Of course it isn't. I am not sure what are you trying to say. This is too brief. Thanks Vivek > > Vivek Goyal wrote: > >On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: > >> On Mon, Dec 9, 2013 at 4:34 PM, H. Peter

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread H. Peter Anvin
Of course it isn't. Vivek Goyal wrote: >On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: >> On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin wrote: >> > On 12/09/2013 04:16 PM, Kees Cook wrote: >> >> For general-purpose (i.e. distro) kernel builds it makes sense to >build with >> >>

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Tue, Dec 10, 2013 at 09:35:40AM -0500, Vivek Goyal wrote: > On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: > > On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin wrote: > > > On 12/09/2013 04:16 PM, Kees Cook wrote: > > >> For general-purpose (i.e. distro) kernel builds it makes sense

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: > On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin wrote: > > On 12/09/2013 04:16 PM, Kees Cook wrote: > >> For general-purpose (i.e. distro) kernel builds it makes sense to build > >> with > >> CONFIG_KEXEC to allow end users to choose

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread H. Peter Anvin
On 12/10/2013 10:33 AM, Vivek Goyal wrote: On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: Of course it isn't. I am not sure what are you trying to say. This is too brief. Thanks Vivek Of course it is not sufficient. Once you can get arbitrary code into kernel space

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Tue, Dec 10, 2013 at 10:54:00AM -0800, H. Peter Anvin wrote: On 12/10/2013 10:33 AM, Vivek Goyal wrote: On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: Of course it isn't. I am not sure what are you trying to say. This is too brief. Thanks Vivek Of course

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Kees Cook
On Tue, Dec 10, 2013 at 11:14 AM, Vivek Goyal vgo...@redhat.com wrote: On Tue, Dec 10, 2013 at 10:54:00AM -0800, H. Peter Anvin wrote: On 12/10/2013 10:33 AM, Vivek Goyal wrote: On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: Of course it isn't. I am not sure what are you

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin h...@zytor.com wrote: On 12/09/2013 04:16 PM, Kees Cook wrote: For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Tue, Dec 10, 2013 at 09:35:40AM -0500, Vivek Goyal wrote: On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin h...@zytor.com wrote: On 12/09/2013 04:16 PM, Kees Cook wrote: For general-purpose (i.e. distro) kernel builds it makes

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread H. Peter Anvin
Of course it isn't. Vivek Goyal vgo...@redhat.com wrote: On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin h...@zytor.com wrote: On 12/09/2013 04:16 PM, Kees Cook wrote: For general-purpose (i.e. distro) kernel builds it makes sense to

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-10 Thread Vivek Goyal
On Tue, Dec 10, 2013 at 08:32:38AM -0800, H. Peter Anvin wrote: Of course it isn't. I am not sure what are you trying to say. This is too brief. Thanks Vivek Vivek Goyal vgo...@redhat.com wrote: On Mon, Dec 09, 2013 at 05:06:10PM -0800, Kees Cook wrote: On Mon, Dec 9, 2013 at 4:34 PM, H.

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-09 Thread Kees Cook
On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin wrote: > On 12/09/2013 04:16 PM, Kees Cook wrote: >> For general-purpose (i.e. distro) kernel builds it makes sense to build with >> CONFIG_KEXEC to allow end users to choose what kind of things they want to do >> with kexec. However, in the face of

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-09 Thread H. Peter Anvin
On 12/09/2013 04:16 PM, Kees Cook wrote: > For general-purpose (i.e. distro) kernel builds it makes sense to build with > CONFIG_KEXEC to allow end users to choose what kind of things they want to do > with kexec. However, in the face of trying to lock down a system with such > a kernel, there

[PATCH v2] kexec: add sysctl to disable kexec

2013-12-09 Thread Kees Cook
For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec. However, in the face of trying to lock down a system with such a kernel, there needs to be a way to disable kexec (much like module

[PATCH v2] kexec: add sysctl to disable kexec

2013-12-09 Thread Kees Cook
For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec. However, in the face of trying to lock down a system with such a kernel, there needs to be a way to disable kexec (much like module

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-09 Thread H. Peter Anvin
On 12/09/2013 04:16 PM, Kees Cook wrote: For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec. However, in the face of trying to lock down a system with such a kernel, there needs

Re: [PATCH v2] kexec: add sysctl to disable kexec

2013-12-09 Thread Kees Cook
On Mon, Dec 9, 2013 at 4:34 PM, H. Peter Anvin h...@zytor.com wrote: On 12/09/2013 04:16 PM, Kees Cook wrote: For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec. However, in the