From: hpa@zytor.com
To: Borislav Petkov <bp@alien8.de>, Kees Cook <keescook@chromium.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
x86@kernel.org, linux-kernel@vger.kernel.org,
Thomas Lendacky <Thomas.Lendacky@amd.com>,
Mauro Rossi <issor.oruam@gmail.com>, Michael Matz <matz@suse.de>
Subject: Re: [PATCH v3] x86/vmlinux: Fix vmlinux.lds.S with pre-2.23 binutils
Date: Tue, 14 Jan 2020 13:50:05 -0800 [thread overview]
Message-ID: <27433E59-971A-4885-B74C-2D6844372FE6@zytor.com> (raw)
In-Reply-To: <20200114165135.GK31032@zn.tnic>
On January 14, 2020 8:51:35 AM PST, Borislav Petkov <bp@alien8.de> wrote:
>On Mon, Jan 13, 2020 at 05:53:32PM -0800, Kees Cook wrote:
>> NAK: linkers can add things at the end of .text that will go missing
>from
>> the kernel if _etext isn't _outside_ the .text section, truly beyond
>the
>> end of the .text section. This patch will break Control Flow
>Integrity
>> checking since the jump tables are at the end of .text.
>
>Err, which linkers are those? Please elaborate.
>
>In any case, after reading the thread, I can't help but favor the idea
>of us bumping min binutils version to 2.23.
>
>Michael (on Cc) says that the 2.21 was kinda broken wrt to the symbols
>fun outside of sections, 2.22 tried to fix it, see
>
>fd952815307f ("x86-32, relocs: Whitelist more symbols for ld bug
>workaround")
>
>which Arvind pointed out and 2.23 fixed it for real.
>
>Now, 2.23 is still very ancient. I'm looking at our releases: openSUSE
>12.1 has the minimum supported gcc version 4.6 by the kernel and
>also the minimum binutils version 2.21 which we support according to
>Documentation/process/changes.rst
>
>Now, openSUSE 12.1 is ancient and we ourselves advise people to update
>to current distros so I don't think anyone would still run it.
>
>So, considering that upping the binutils version would save us from all
>this trouble I say we try it after 5.5 releases for a maximum time of a
>full 5.6 release cycle and see who complains.
>
>Considering how no one triggered this yet until Arvind, I think no one
>would complain. But I might be wrong.
>
>So what do people think? hpa?
I'm all for dumping support for an ancient, known buggy binutils.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
next prev parent reply other threads:[~2020-01-14 21:50 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-10 20:23 [PATCH] x86/tools/relocs: Add _etext and __end_of_kernel_reserve to S_REL Arvind Sankar
2020-01-10 20:38 ` Borislav Petkov
2020-01-10 20:50 ` Arvind Sankar
2020-01-10 21:50 ` [PATCH v2] " Arvind Sankar
2020-01-10 21:52 ` Arvind Sankar
2020-01-11 13:02 ` [PATCH] " Borislav Petkov
2020-01-11 17:20 ` Arvind Sankar
2020-01-11 17:32 ` Arvind Sankar
2020-01-13 13:43 ` Borislav Petkov
2020-01-13 16:13 ` Arvind Sankar
2020-01-13 16:38 ` Borislav Petkov
2020-01-13 17:59 ` Arvind Sankar
2020-01-13 18:08 ` Borislav Petkov
2020-01-14 4:17 ` Arvind Sankar
2020-01-14 11:25 ` Borislav Petkov
2020-01-14 16:32 ` Arvind Sankar
2020-01-14 4:08 ` Arvind Sankar
2020-01-13 19:53 ` [PATCH v3] x86/vmlinux: Fix vmlinux.lds.S with pre-2.23 binutils Arvind Sankar
2020-01-13 21:46 ` Tom Lendacky
2020-01-13 23:06 ` Arvind Sankar
2020-01-14 1:53 ` Kees Cook
2020-01-14 1:57 ` H. Peter Anvin
2020-01-14 2:20 ` Kees Cook
2020-01-14 3:58 ` Arvind Sankar
2020-01-14 5:05 ` hpa
2020-01-14 16:51 ` Borislav Petkov
2020-01-14 21:50 ` hpa [this message]
2020-01-15 0:21 ` Arvind Sankar
2020-01-15 12:24 ` Borislav Petkov
2020-03-16 16:02 ` [PATCH] Documentation/changes: Raise minimum supported binutils version to 2.23 Borislav Petkov
2020-03-16 20:54 ` Kees Cook
2020-03-23 20:44 ` Jason A. Donenfeld
2020-03-23 20:51 ` Kees Cook
2020-03-23 21:11 ` Jason A. Donenfeld
2020-03-25 17:33 ` David Laight
2020-03-24 9:02 ` Masahiro Yamada
2020-03-24 9:12 ` Masahiro Yamada
2020-03-24 15:38 ` Arvind Sankar
2020-03-24 17:31 ` Masahiro Yamada
2020-03-24 21:36 ` Arvind Sankar
2020-03-24 9:14 ` Borislav Petkov
2020-03-24 9:40 ` Masahiro Yamada
2020-03-24 12:00 ` Borislav Petkov
2020-03-24 16:22 ` Jason A. Donenfeld
2020-03-24 16:28 ` Borislav Petkov
2020-03-24 16:37 ` Linus Torvalds
2020-03-24 16:48 ` Borislav Petkov
2020-03-24 21:42 ` Arvind Sankar
2020-03-24 22:01 ` Arvind Sankar
2020-03-24 22:14 ` Linus Torvalds
2020-03-24 23:49 ` Arvind Sankar
2020-03-24 17:53 ` Kees Cook
2020-03-23 20:50 ` [PATCH] Documentation/changes: Raise minimum supported binutilsa " Nick Desaulniers
2020-01-13 23:38 ` [PATCH] x86/tools/relocs: Add _etext and __end_of_kernel_reserve to S_REL Arvind Sankar
2020-01-10 20:56 ` Kees Cook
[not found] ` <CAEQFVGa4fksPRtiLtBckSgbJY_JSHr07hoy5+5w-pAYym16YVg@mail.gmail.com>
2020-01-11 19:40 ` Fwd: " Mauro Rossi
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