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From: Will Deacon <>
To: Mark Rutland <>
	Catalin Marinas <>,
	Kees Cook <>,
	Sami Tolvanen <>,
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 <>
> This looks correct to me, builds fine, and I asume has been tested, so FWIW:
> Acked-by: Mark Rutland <>
> 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.


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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

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