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Date:   Sat, 14 May 2022 14:51:47 -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 10/21] arm64: Add CFI error handling
Message-ID: <202205141451.AABEE8B@keescook>
References: <20220513202159.1550547-1-samitolvanen@google.com>
 <20220513202159.1550547-11-samitolvanen@google.com>
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On Fri, May 13, 2022 at 01:21:48PM -0700, Sami Tolvanen wrote:
> With -fsanitize=kcfi, CFI always traps. Add arm64 support for handling
> CFI failures. The registers containing the target address and the
> expected type are encoded in the first ten bits of the ESR as follows:
> 
>  - 0-4: n, where the register Xn contains the target address
>  - 5-9: m, where the register Wm contains the type hash
> 
> Suggested-by: Mark Rutland <mark.rutland@arm.com>
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

It might be nice just to include an example exception Oops in this
commit log.

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

-- 
Kees Cook