Re: [PATCH v3 01/12] ELF: UAPI and Kconfig additions for ELF program properties

From: Kees Cook
Date: Tue Oct 29 2019 - 19:08:02 EST


On Fri, Oct 18, 2019 at 06:25:34PM +0100, Dave Martin wrote:
> Pull the basic ELF definitions relating to the
> NT_GNU_PROPERTY_TYPE_0 note from Yu-Cheng Yu's earlier x86 shstk
> series.
>
> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-Kees

> Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
> ---
> fs/Kconfig.binfmt | 3 +++
> include/linux/elf.h | 8 ++++++++
> include/uapi/linux/elf.h | 1 +
> 3 files changed, 12 insertions(+)
>
> diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt
> index 62dc4f5..d2cfe07 100644
> --- a/fs/Kconfig.binfmt
> +++ b/fs/Kconfig.binfmt
> @@ -36,6 +36,9 @@ config COMPAT_BINFMT_ELF
> config ARCH_BINFMT_ELF_STATE
> bool
>
> +config ARCH_USE_GNU_PROPERTY
> + bool
> +
> config BINFMT_ELF_FDPIC
> bool "Kernel support for FDPIC ELF binaries"
> default y if !BINFMT_ELF
> diff --git a/include/linux/elf.h b/include/linux/elf.h
> index e3649b3..459cddc 100644
> --- a/include/linux/elf.h
> +++ b/include/linux/elf.h
> @@ -2,6 +2,7 @@
> #ifndef _LINUX_ELF_H
> #define _LINUX_ELF_H
>
> +#include <linux/types.h>
> #include <asm/elf.h>
> #include <uapi/linux/elf.h>
>
> @@ -56,4 +57,11 @@ static inline int elf_coredump_extra_notes_write(struct coredump_params *cprm) {
> extern int elf_coredump_extra_notes_size(void);
> extern int elf_coredump_extra_notes_write(struct coredump_params *cprm);
> #endif
> +
> +/* NT_GNU_PROPERTY_TYPE_0 header */
> +struct gnu_property {
> + u32 pr_type;
> + u32 pr_datasz;
> +};
> +
> #endif /* _LINUX_ELF_H */
> diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h
> index 34c02e4..c377314 100644
> --- a/include/uapi/linux/elf.h
> +++ b/include/uapi/linux/elf.h
> @@ -36,6 +36,7 @@ typedef __s64 Elf64_Sxword;
> #define PT_LOPROC 0x70000000
> #define PT_HIPROC 0x7fffffff
> #define PT_GNU_EH_FRAME 0x6474e550
> +#define PT_GNU_PROPERTY 0x6474e553
>
> #define PT_GNU_STACK (PT_LOOS + 0x474e551)
>
> --
> 2.1.4
>

--
Kees Cook