Linux-ARM-Kernel Archive on lore.kernel.org
 help / color / Atom feed
From: Will Deacon <will@kernel.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org,
	Catalin Marinas <catalin.marinas@arm.com>,
	Kees Cook <keescook@chromium.org>,
	Sami Tolvanen <samitolvanen@google.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] arm64: fix function types in COND_SYSCALL
Date: Thu, 12 Sep 2019 14:11:44 +0100
Message-ID: <20190912131143.u3rncvqdgx4z3ckz@willie-the-truck> (raw)
In-Reply-To: <20190911151545.GD3360@blommer>

On Wed, Sep 11, 2019 at 04:15:46PM +0100, Mark Rutland wrote:
> On Tue, Sep 10, 2019 at 03:40:44PM -0700, Sami Tolvanen wrote:
> > Define a weak function in COND_SYSCALL instead of a weak alias to
> > sys_ni_syscall, which has an incompatible type. This fixes indirect
> > call mismatches with Control-Flow Integrity (CFI) checking.
> > 
> > Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
> 
> This looks correct to me, builds fine, and I asume has been tested, so FWIW:
> 
> Acked-by: Mark Rutland <mark.rutland@arm.com>
> 
> In looking at this, I came to the conclusion that we can drop the ifdeffery
> around our SYSCALL_DEFINE0(), COND_SYSCALL(), and SYS_NI(), which I evidently
> cargo-culted from x86 (where the ifdeffery is actually necessary).

Curious: why is it required on x86?

> I can send a follow up for that.

Yes, please.

Will

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply index

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-10 22:40 Sami Tolvanen
2019-09-11 15:15 ` Mark Rutland
2019-09-12 13:11   ` Will Deacon [this message]
2019-09-13 11:33     ` Mark Rutland

Reply instructions:

You may reply publically 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=20190912131143.u3rncvqdgx4z3ckz@willie-the-truck \
    --to=will@kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=keescook@chromium.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=samitolvanen@google.com \
    /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

Linux-ARM-Kernel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-arm-kernel/0 linux-arm-kernel/git/0.git
	git clone --mirror https://lore.kernel.org/linux-arm-kernel/1 linux-arm-kernel/git/1.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-arm-kernel linux-arm-kernel/ https://lore.kernel.org/linux-arm-kernel \
		linux-arm-kernel@lists.infradead.org
	public-inbox-index linux-arm-kernel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-arm-kernel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git