Re: [PATCH 00/14] Prepare syscall_get_arch for PTRACE_GET_SYSCALL_INFO

[Richard Guy Briggs]

On 2019-01-09 15:40, Dmitry V. Levin wrote:
> syscall_get_arch() is required to be implemented on all architectures in order
> to extend the generic ptrace API with PTRACE_GET_SYSCALL_INFO request:
> syscall_get_arch() is going to be called from ptrace_request() along with
> syscall_get_nr(), syscall_get_arguments(), syscall_get_error(), and
> syscall_get_return_value() functions with a tracee as their argument.
> 
> The primary intent is that the triple (audit_arch, syscall_nr, arg1..arg6)
> should describe what system call is being called and what its arguments are.
> 
> This patchset began as a series called "Prepare for PTRACE_GET_SYSCALL_INFO",
> then I merged it into a series called "ptrace: add PTRACE_GET_SYSCALL_INFO request"
> that also contains ptrace-specific changes.
> 
> The ptrace-specific part, however, needs more attention to workaround problems
> on niche architectures like alpha, while the syscall_get_arch() part is
> straightforward, so I decided to split it out into a separate patchset that
> just prepares syscall_get_arch() for PTRACE_GET_SYSCALL_INFO: it adds
> syscall_get_arch() to those architectures that haven't implemented it yet,
> and then adds "struct task_struct *" argument to syscall_get_arch()
> on all architectures.

Glad to see syscall_get_arch() added to the remaining arches.  As Paul
said, it gets us closer to auditing syscalls on those remaining
unsupported arches and getting rid of the extra CONFIG_AUDITSYSCALL.
A little ironic that Eric (Paris) and I purged task_struct from
syscall_get_arch() 5 years ago since everything could use current.

> All patches from this patchset have been already reviewed, so it's ready
> to be merged without waiting for the ptrace-specific part.  As it's all
> about syscall_get_arch(), it should probably go via audit tree.

ACK.

Thanks Dmitry.

> Dmitry V. Levin (14):
>   Move EM_ARCOMPACT and EM_ARCV2 to uapi/linux/elf-em.h
>   arc: define syscall_get_arch()
>   c6x: define syscall_get_arch()
>   h8300: define syscall_get_arch()
>   Move EM_HEXAGON to uapi/linux/elf-em.h
>   hexagon: define syscall_get_arch()
>   m68k: define syscall_get_arch()
>   Move EM_NDS32 to uapi/linux/elf-em.h
>   nds32: define syscall_get_arch()
>   nios2: define syscall_get_arch()
>   riscv: define syscall_get_arch()
>   Move EM_UNICORE to uapi/linux/elf-em.h
>   unicore32: define syscall_get_arch()
>   syscall_get_arch: add "struct task_struct *" argument
> 
>  arch/alpha/include/asm/syscall.h      |  2 +-
>  arch/arc/include/asm/elf.h            |  6 +-----
>  arch/arc/include/asm/syscall.h        | 11 +++++++++++
>  arch/arm/include/asm/syscall.h        |  2 +-
>  arch/arm64/include/asm/syscall.h      |  4 ++--
>  arch/c6x/include/asm/syscall.h        |  7 +++++++
>  arch/csky/include/asm/syscall.h       |  2 +-
>  arch/h8300/include/asm/syscall.h      |  6 ++++++
>  arch/hexagon/include/asm/elf.h        |  6 +-----
>  arch/hexagon/include/asm/syscall.h    |  8 ++++++++
>  arch/ia64/include/asm/syscall.h       |  2 +-
>  arch/m68k/include/asm/syscall.h       | 12 ++++++++++++
>  arch/microblaze/include/asm/syscall.h |  2 +-
>  arch/mips/include/asm/syscall.h       |  6 +++---
>  arch/mips/kernel/ptrace.c             |  2 +-
>  arch/nds32/include/asm/elf.h          |  3 +--
>  arch/nds32/include/asm/syscall.h      |  9 +++++++++
>  arch/nios2/include/asm/syscall.h      |  6 ++++++
>  arch/openrisc/include/asm/syscall.h   |  2 +-
>  arch/parisc/include/asm/syscall.h     |  4 ++--
>  arch/powerpc/include/asm/syscall.h    | 10 ++++++++--
>  arch/riscv/include/asm/syscall.h      | 10 ++++++++++
>  arch/s390/include/asm/syscall.h       |  4 ++--
>  arch/sh/include/asm/syscall_32.h      |  2 +-
>  arch/sh/include/asm/syscall_64.h      |  2 +-
>  arch/sparc/include/asm/syscall.h      |  5 +++--
>  arch/unicore32/include/asm/elf.h      |  3 +--
>  arch/unicore32/include/asm/syscall.h  | 12 ++++++++++++
>  arch/x86/include/asm/syscall.h        |  8 +++++---
>  arch/x86/um/asm/syscall.h             |  2 +-
>  arch/xtensa/include/asm/syscall.h     |  2 +-
>  include/asm-generic/syscall.h         |  5 +++--
>  include/uapi/linux/audit.h            | 14 ++++++++++++++
>  include/uapi/linux/elf-em.h           |  6 ++++++
>  kernel/auditsc.c                      |  4 ++--
>  kernel/seccomp.c                      |  4 ++--
>  36 files changed, 148 insertions(+), 47 deletions(-)
>  create mode 100644 arch/m68k/include/asm/syscall.h
>  create mode 100644 arch/unicore32/include/asm/syscall.h
> 
> -- 
> ldv

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635