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

From: Kees Cook <keescook@chromium.org>
To: Dave Martin <Dave.Martin@arm.com>
Cc: linux-kernel@vger.kernel.org, "Andrew Jones" <drjones@redhat.com>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Eugene Syromiatnikov" <esyr@redhat.com>,
	"Florian Weimer" <fweimer@redhat.com>,
	"H.J. Lu" <hjl.tools@gmail.com>, "Jann Horn" <jannh@google.com>,
	"Kristina Martšenko" <kristina.martsenko@arm.com>,
	"Marc Zyngier" <maz@kernel.org>,
	"Mark Brown" <broonie@kernel.org>,
	"Paul Elliott" <paul.elliott@arm.com>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Richard Henderson" <richard.henderson@linaro.org>,
	"Sudakshina Das" <sudi.das@arm.com>,
	"Szabolcs Nagy" <szabolcs.nagy@arm.com>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Will Deacon" <will@kernel.org>,
	"Yu-cheng Yu" <yu-cheng.yu@intel.com>,
	"Amit Kachhap" <amit.kachhap@arm.com>
Subject: Re: [PATCH v3 01/12] ELF: UAPI and Kconfig additions for ELF program properties
Date: Tue, 29 Oct 2019 16:07:57 -0700	[thread overview]
Message-ID: <201910291607.F5DA2EE@keescook> (raw)
In-Reply-To: <1571419545-20401-2-git-send-email-Dave.Martin@arm.com>

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@intel.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

> Signed-off-by: Dave Martin <Dave.Martin@arm.com>
> ---
>  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