On 11/03/2015 03:42 PM, Kees Cook wrote:
On Tue, Nov 3, 2015 at 1:48 PM, Laura Abbott <[email protected]> wrote:
Hi,
Based on a recent discussion[1] there is interest in having set_memory_* work
on kernel memory for security and other use cases. This patch adds the
ability for that to happen behind a kernel option. If this is welcome enough,
the Kconfig can be dropped. This has been briefly tested but not stress tested.
Thanks,
Laura
[1]
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-October/382079.html
Laura Abbott (2):
arm64: Get existing page protections in split_pmd
arm64: Allow changing of attributes outside of modules
arch/arm64/Kconfig.debug | 11 +++++++
arch/arm64/mm/mm.h | 3 ++
arch/arm64/mm/mmu.c | 11 ++++---
arch/arm64/mm/pageattr.c | 74 ++++++++++++++++++++++++++++++++++++++++++++----
4 files changed, 88 insertions(+), 11 deletions(-)
This seems like the right thing to have. What's arm64 doing for the
equivalent of x86 and arm's set_kernel_text_* functions? x86 and arm
call their set_memory_* functions, for example. A quick examination
shows mm/mmu.c is just doing it "by hand" in fixup_executable and
mark_rodata_ro? Could those functions use the new set_memory_* ones?
It looks like mark_rodata_ro could probably use the set_memory_ro. I'll
have to test it out. Longer term, the page table setup code should
probably just be pulled out into a common file.
Do you know the code path in ftrace which would trigger the set_kernel_text_*
If not, I'll go see if I can figure out if it's implemented yet on arm64.
-Kees
Thanks,
Laura
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
