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Date:   Sat, 14 May 2022 14:46:50 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Sami Tolvanen <samitolvanen@google.com>
Cc:     linux-kernel@vger.kernel.org, Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, x86@kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Joao Moreira <joao@overdrivepizza.com>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-hardening@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev
Subject: Re: [RFC PATCH v2 06/21] cfi: Switch to -fsanitize=kcfi
Message-ID: <202205141444.9F32C94D9@keescook>
References: <20220513202159.1550547-1-samitolvanen@google.com>
 <20220513202159.1550547-7-samitolvanen@google.com>
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On Fri, May 13, 2022 at 01:21:44PM -0700, Sami Tolvanen wrote:
> Switch from Clang's original forward-edge control-flow integrity
> implementation to -fsanitize=kcfi, which is better suited for the
> kernel, as it doesn't require LTO, doesn't use a jump table that
> requires altering function references, and won't break cross-module
> function address equality.
> 
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Yes please. And just to note it somewhere: landing the KCFI
implementation on Clang depends on this series being accepted (i.e. if
the arm64 and x86 maintainers are happy with this series, then that'll
unblock landing it in Clang (no reason to land something that won't get
used.)

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook