2017-12-04 14:25:13

by Jinbum Park

Subject: [kernel-hardening][PATCH v3 0/3] arm: Makes ptdump resuable and add WX page checking

Hi,

Page table dumping code for arm64-x86 is reusable,
and they have function for WX page checking.
But arm doesn't have that.

This path series are to makes ptdump reusable,
and add WX page checking for arm.
This is heavily based on arm64 version.

v2 :
Fix a sender name of mail header, there was an mistake.
(from "jinb.park" to Jinbum Park)
Contents of patch-set are perfectly same.

v3 :
Take advantage of the existing pg_level and bits arrays
to check ro, nx prot.

jinb.park (3):
arm: mm: dump: make page table dumping reusable
arm: mm: dump: make the page table dumping seq_file optional
arm: mm: dump: add checking for writable and executable pages

arch/arm/Kconfig.debug | 33 +++++++++-
arch/arm/include/asm/ptdump.h | 56 ++++++++++++++++
arch/arm/mm/Makefile | 3 +-
arch/arm/mm/dump.c | 144 +++++++++++++++++++++++++++++-------------
arch/arm/mm/init.c | 2 +
arch/arm/mm/ptdump_debugfs.c | 34 ++++++++++
6 files changed, 226 insertions(+), 46 deletions(-)
create mode 100644 arch/arm/include/asm/ptdump.h
create mode 100644 arch/arm/mm/ptdump_debugfs.c

--
1.9.1

2017-12-05 19:56:16

by Kees Cook

Subject: Re: [kernel-hardening][PATCH v3 0/3] arm: Makes ptdump resuable and add WX page checking

On Mon, Dec 4, 2017 at 6:24 AM, Jinbum Park <[email protected]> wrote:
> Hi,
>
> Page table dumping code for arm64-x86 is reusable,
> and they have function for WX page checking.
> But arm doesn't have that.
>
> This path series are to makes ptdump reusable,
> and add WX page checking for arm.
> This is heavily based on arm64 version.

Thanks for working on this! I sent along a few nits.

-Kees

>
> v2 :
> Fix a sender name of mail header, there was an mistake.
> (from "jinb.park" to Jinbum Park)
> Contents of patch-set are perfectly same.
>
> v3 :
> Take advantage of the existing pg_level and bits arrays
> to check ro, nx prot.
>
> jinb.park (3):
> arm: mm: dump: make page table dumping reusable
> arm: mm: dump: make the page table dumping seq_file optional
> arm: mm: dump: add checking for writable and executable pages
>
> arch/arm/Kconfig.debug | 33 +++++++++-
> arch/arm/include/asm/ptdump.h | 56 ++++++++++++++++
> arch/arm/mm/Makefile | 3 +-
> arch/arm/mm/dump.c | 144 +++++++++++++++++++++++++++++-------------
> arch/arm/mm/init.c | 2 +
> arch/arm/mm/ptdump_debugfs.c | 34 ++++++++++
> 6 files changed, 226 insertions(+), 46 deletions(-)
> create mode 100644 arch/arm/include/asm/ptdump.h
> create mode 100644 arch/arm/mm/ptdump_debugfs.c
>
> --
> 1.9.1
>



--
Kees Cook
Pixel Security

2017-12-05 23:54:13

by Laura Abbott

Subject: Re: [kernel-hardening][PATCH v3 0/3] arm: Makes ptdump resuable and add WX page checking

On 12/04/2017 06:24 AM, Jinbum Park wrote:
> Hi,
>
> Page table dumping code for arm64-x86 is reusable,
> and they have function for WX page checking.
> But arm doesn't have that.
>
> This path series are to makes ptdump reusable,
> and add WX page checking for arm.
> This is heavily based on arm64 version.
>
> v2 :
> Fix a sender name of mail header, there was an mistake.
> (from "jinb.park" to Jinbum Park)
> Contents of patch-set are perfectly same.
>
> v3 :
> Take advantage of the existing pg_level and bits arrays
> to check ro, nx prot.
>
> jinb.park (3):
> arm: mm: dump: make page table dumping reusable
> arm: mm: dump: make the page table dumping seq_file optional
> arm: mm: dump: add checking for writable and executable pages
>
> arch/arm/Kconfig.debug | 33 +++++++++-
> arch/arm/include/asm/ptdump.h | 56 ++++++++++++++++
> arch/arm/mm/Makefile | 3 +-
> arch/arm/mm/dump.c | 144 +++++++++++++++++++++++++++++-------------
> arch/arm/mm/init.c | 2 +
> arch/arm/mm/ptdump_debugfs.c | 34 ++++++++++
> 6 files changed, 226 insertions(+), 46 deletions(-)
> create mode 100644 arch/arm/include/asm/ptdump.h
> create mode 100644 arch/arm/mm/ptdump_debugfs.c
>

This detects the issue fixed by 400eeffaffc7 ("ARM: 8722/1: mm:
make STRICT_KERNEL_RWX effective for LPAE"). I'll give it another
test after the next version.

Thanks,
Laura