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Date:   Wed, 13 Oct 2021 12:07:51 -0700
From:   Kees Cook <keescook@chromium.org>
To:     x86@kernel.org, Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Sami Tolvanen <samitolvanen@google.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev
Subject: Re: [PATCH v5 00/15] x86: Add support for Clang CFI
Message-ID: <202110131206.9D4B6A7F0@keescook>
References: <20211013181658.1020262-1-samitolvanen@google.com>
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On Wed, Oct 13, 2021 at 11:16:43AM -0700, Sami Tolvanen wrote:
> This series adds support for Clang's Control-Flow Integrity (CFI)
> checking to x86_64. With CFI, the compiler injects a runtime
> check before each indirect function call to ensure the target is
> a valid function with the correct static type. This restricts
> possible call targets and makes it more difficult for an attacker
> to exploit bugs that allow the modification of stored function
> pointers. For more details, see:
> 
>   https://clang.llvm.org/docs/ControlFlowIntegrity.html
> 
> Note that v5 is based on tip/master. The first two patches contain
> objtool support for CFI, the remaining patches change function
> declarations to use opaque types, fix type mismatch issues that
> confuse the compiler, and disable CFI where it can't be used.

x86 folks: I'd prefer this series went via -tip, but I can carry it for
-next as well. What would you like to do here? I think it's ready.

Thanks!

-Kees

-- 
Kees Cook