From: Bill Wendling <morbo@google.com>
To: Mark Brown <broonie@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
Kees Cook <keescook@google.com>, Ard Biesheuvel <ardb@kernel.org>,
Will Deacon <will@kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-arm-kernel@lists.infradead.org,
Szabolcs Nagy <szabolcs.nagy@arm.com>,
Daniel Kiss <Daniel.Kiss@arm.com>
Subject: Re: [PATCH] arm64/vdso: Discard .note.gnu.property sections in vDSO
Date: Wed, 28 Apr 2021 12:21:38 -0700 [thread overview]
Message-ID: <CAGG=3QUATefn9AG+HvnCfEOBv3iRu4fzFwfmA7Djrh2CmP_weA@mail.gmail.com> (raw)
In-Reply-To: <20210428174010.GA4593@sirena.org.uk>
On Wed, Apr 28, 2021 at 10:40 AM Mark Brown <broonie@kernel.org> wrote:
> On Wed, Apr 28, 2021 at 06:28:47PM +0100, Catalin Marinas wrote:
> > On Fri, Apr 23, 2021 at 01:51:59PM -0700, Bill Wendling wrote:
>
> > > Since the note.gnu.property section in the vDSO is not checked by the
> > > dynamic linker, discard the .note.gnu.property sections in the vDSO.
>
> > Can we not instead fix the linker script to preserve the
> > .note.gnu.property, correctly aligned? It doesn't take much space and
> > while we don't use it now, it has the BTI information about the binary.
>
> > Cc'ing a few others who were involved in the BTI support.
>
> Not just BTI, we also flag PAC usage in there too and could add other
> extensions going forwards. While the note isn't actively used by
> anything right now due to the kernel mapping the vDSO prior to userspace
> starting it is part of the ABI and something could end up wanting to use
> it and getting confused if it's not there. It would be much better to
> fix the alignment issue.
If there's only one of the 8-byte aligned sections guaranteed, we
could place it first in the note. Otherwise, we will have to change
the alignment of the note (or somehow merge multiple notes).
-bw
next prev parent reply other threads:[~2021-04-28 19:21 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-23 20:51 [PATCH] arm64/vdso: Discard .note.gnu.property sections in vDSO Bill Wendling
2021-04-27 22:58 ` Kees Cook
2021-04-28 8:51 ` Ard Biesheuvel
2021-04-28 17:28 ` Catalin Marinas
2021-04-28 17:40 ` Mark Brown
2021-04-28 19:21 ` Bill Wendling [this message]
2021-04-28 19:31 ` Bill Wendling
2021-04-29 7:54 ` Szabolcs Nagy
2021-04-29 9:23 ` Bill Wendling
2021-04-29 9:50 ` Szabolcs Nagy
2021-04-29 18:52 ` Bill Wendling
2021-04-30 8:16 ` Szabolcs Nagy
2021-04-30 8:29 ` Bill Wendling
2021-04-30 17:57 ` Catalin Marinas
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAGG=3QUATefn9AG+HvnCfEOBv3iRu4fzFwfmA7Djrh2CmP_weA@mail.gmail.com' \
--to=morbo@google.com \
--cc=Daniel.Kiss@arm.com \
--cc=ardb@kernel.org \
--cc=broonie@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=keescook@google.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=szabolcs.nagy@arm.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).