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Date:   Thu, 12 Jan 2023 22:49:47 +0000
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Message-ID: <20230112224948.1479453-1-samitolvanen@google.com>
Subject: [PATCH 0/1] Fix CFI hash randomization with KASAN
From:   Sami Tolvanen <samitolvanen@google.com>
To:     "Peter Zijlstra (Intel)" <peterz@infradead.org>,
        Masahiro Yamada <masahiroy@kernel.org>
Cc:     Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Kees Cook <keescook@chromium.org>,
        linux-kbuild@vger.kernel.org, llvm@lists.linux.dev,
        linux-kernel@vger.kernel.org,
        Sami Tolvanen <samitolvanen@google.com>
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Peter, Masahiro,

I noticed that KASAN+CFI fails to boot on x86_64 without
cfi=norand. The randomization code is missing a couple of KASAN
constructors in object files that are not part of vmlinux.o. This
happens because we don't run objtool for the files, which means
the type hashes are not included in the .cfi_sites section.

This patch simply disables KASAN for these files, which seems
reasonable to me and fixes the boot issue, but perhaps you have
better ideas?

Sami


Sami Tolvanen (1):
  kbuild: Fix CFI hash randomization with KASAN

 init/Makefile            | 1 +
 scripts/Makefile.vmlinux | 1 +
 2 files changed, 2 insertions(+)


base-commit: c757fc92a3f73734872c7793b97f06434773d65d
-- 
2.39.0.314.g84b9a713c41-goog