Re: [PATCH v1 0/3] perf/binfmt/mm: remove in-tree usage of MAP_EXECUTABLE

From: ebiederm@xmission.com (Eric W. Biederman)
To: David Hildenbrand <david@redhat.com>
Cc: linux-kernel@vger.kernel.org,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Peter Zijlstra <peterz@infradead.org>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Kees Cook <keescook@chromium.org>,
	Greg Ungerer <gerg@linux-m68k.org>,
	Mike Rapoport <rppt@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Kevin Brodsky <Kevin.Brodsky@arm.com>,
	Michal Hocko <mhocko@suse.com>, Feng Tang <feng.tang@intel.com>,
	Don Zickus <dzickus@redhat.com>,
	x86@kernel.org, linux-fsdevel@vger.kernel.org,
	linux-mm@kvack.org
Subject: Re: [PATCH v1 0/3] perf/binfmt/mm: remove in-tree usage of MAP_EXECUTABLE
Date: Wed, 21 Apr 2021 14:03:49 -0500	[thread overview]
Message-ID: <m1eef3qx2i.fsf@fess.ebiederm.org> (raw)
In-Reply-To: <20210421093453.6904-1-david@redhat.com> (David Hildenbrand's message of "Wed, 21 Apr 2021 11:34:50 +0200")

David Hildenbrand <david@redhat.com> writes:

> Stumbling over the history of MAP_EXECUTABLE, I noticed that we still
> have some in-tree users that we can get rid of.
>
> A good fit for the whole series could be Andrew's tree.

In general this looks like a good cleanup.

Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>

As far as I can see we can go after MAP_DENYWRITE the same way.
Today deny_write_access in open_exec is what causes -ETXTBSY
when attempting to write to file that is current executing.

Do you have any plans to look at that?

Eric

> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Alexander Viro <viro@zeniv.linux.org.uk>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
> Cc: Jiri Olsa <jolsa@redhat.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
> Cc: Greg Ungerer <gerg@linux-m68k.org>
> Cc: Mike Rapoport <rppt@kernel.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Kevin Brodsky <Kevin.Brodsky@arm.com>
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: Feng Tang <feng.tang@intel.com>
> Cc: Don Zickus <dzickus@redhat.com>
> Cc: x86@kernel.org
> Cc: linux-fsdevel@vger.kernel.org
> Cc: linux-mm@kvack.org
>
> David Hildenbrand (3):
>   perf: MAP_EXECUTABLE does not indicate VM_MAYEXEC
>   binfmt: remove in-tree usage of MAP_EXECUTABLE
>   mm: ignore MAP_EXECUTABLE in ksys_mmap_pgoff()
>
>  arch/x86/ia32/ia32_aout.c |  4 ++--
>  fs/binfmt_aout.c          |  4 ++--
>  fs/binfmt_elf.c           |  2 +-
>  fs/binfmt_elf_fdpic.c     | 11 ++---------
>  fs/binfmt_flat.c          |  2 +-
>  include/linux/mman.h      |  2 ++
>  kernel/events/core.c      |  2 --
>  mm/mmap.c                 |  2 +-
>  mm/nommu.c                |  2 +-
>  9 files changed, 12 insertions(+), 19 deletions(-)