[PATCH 0/2] RFC: Support for MTE stack tagging.

[Cupertino Miranda]

+CC Indu Bhagat <indu.bhagat@oracle.com>

On 14-03-2025 13:21, Cupertino Miranda wrote:
> Hi everyone,
> 
> This is an initial work to enable glibc support for MTE stack tagging.
> In a nutshell glibc should set PROT_MTE to any stack pages which get
> allocated for any running application which requires MTE stack tagging.
> 
> The approach taken to flag the need for stack tagging is to check
> .dynamic entries specific to aarch64, as described in section 6 from:
> https://github.com/ARM-software/abi-aa/blob/main/memtagabielf64/memtagabielf64.rst
> 
> This is an initial propose patch. I would like to get some feedback
> for the approach used to check for the .dynamic flags, how the
> PROT_MTE property is set for the stacks or any other comments.
> 
> This feature is related to the work done by Indu Bhagat submitted as RFC
> in gcc-patches:
>    https://gcc.gnu.org/pipermail/gcc-patches/2024-November/668017.html
> And in binutils in:
>    https://sourceware.org/pipermail/binutils/2024-December/137989.html
> 
> I noticed my patches fail a lot of conform/linknamespace tests. I
> think I need some guidance for why this happens.
> 
> Looking forward to your comments.
> 
> Best regards,
> Cupertino
> 
> Cupertino Miranda (2):
>    rtld: Enable MTE for stack when specified in .dynamic.
>    nptl: Enable MTE for stacks created for threads.
> 
>   elf/dl-mte-stack.c                            | 28 +++++++
>   elf/elf.h                                     |  8 +-
>   nptl/allocatestack.c                          |  3 +-
>   nptl/nptl-stack.c                             |  7 ++
>   nptl/nptl-stack.h                             |  2 +
>   sysdeps/aarch64/Makefile                      |  3 +-
>   sysdeps/aarch64/cpu-features.h                | 15 ++++
>   sysdeps/aarch64/dl-mte.c                      | 50 +++++++++++
>   sysdeps/aarch64/dl-prop.h                     |  4 +
>   sysdeps/unix/sysv/linux/aarch64/Makefile      | 10 +++
>   .../unix/sysv/linux/aarch64/dl-mte-stack.c    | 83 +++++++++++++++++++
>   11 files changed, 210 insertions(+), 3 deletions(-)
>   create mode 100644 elf/dl-mte-stack.c
>   create mode 100644 sysdeps/aarch64/dl-mte.c
>   create mode 100644 sysdeps/unix/sysv/linux/aarch64/dl-mte-stack.c
>