On Thu, Sep 26, 2019 at 10:55:33AM -0700, Kees Cook wrote:
> This series works to move the linker sections for NOTES and
> EXCEPTION_TABLE into the RO_DATA area, where they belong on most
> (all?) architectures. The problem being addressed was the discovery
> by Rick Edgecombe that the exception table was accidentally marked
> executable while he was developing his execute-only-memory series. When
> permissions were flipped from readable-and-executable to only-executable,
> the exception table became unreadable, causing things to explode rather
> badly. :)
>
> Roughly speaking, the steps are:
>
> - regularize the linker names for PT_NOTE and PT_LOAD program headers
> (to "note" and "text" respectively)
> - regularize restoration of linker section to program header assignment
> (when PT_NOTE exists)
> - move NOTES into RO_DATA
> - finish macro naming conversions for RO_DATA and RW_DATA
> - move EXCEPTION_TABLE into RO_DATA on architectures where this is clear
> - clean up some x86-specific reporting of kernel memory resources
> - switch x86 linker fill byte from x90 (NOP) to 0xcc (INT3), just because
> I finally realized what that trailing ": 0x9090" meant -- and we should
> trap, not slide, if execution lands in section padding
Yap, nice patchset overall.
> Since these changes are treewide, I'd love to get architecture-maintainer
> Acks and either have this live in x86 -tip or in my own tree, however
> people think it should go.
Sure, I don't mind taking v2 through tip once I get ACKs from the
respective arch maintainers.
Thx.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
