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Date:   Fri, 18 Oct 2019 09:10:26 -0700
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Subject: [PATCH 11/18] kprobes: disable kretprobes with SCS
From:   Sami Tolvanen <samitolvanen@google.com>
To:     Will Deacon <will@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Dave Martin <Dave.Martin@arm.com>,
        Kees Cook <keescook@chromium.org>,
        Laura Abbott <labbott@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        clang-built-linux@googlegroups.com,
        kernel-hardening@lists.openwall.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Sami Tolvanen <samitolvanen@google.com>
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Sender: linux-kernel-owner@vger.kernel.org
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With CONFIG_KRETPROBES, function return addresses are modified to
redirect control flow to kretprobe_trampoline. This is incompatible with
return address protection.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
 arch/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index a222adda8130..4646e3b34925 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -171,7 +171,7 @@ config ARCH_USE_BUILTIN_BSWAP
 
 config KRETPROBES
 	def_bool y
-	depends on KPROBES && HAVE_KRETPROBES
+	depends on KPROBES && HAVE_KRETPROBES && ROP_PROTECTION_NONE
 
 config USER_RETURN_NOTIFIER
 	bool
-- 
2.23.0.866.gb869b98d4c-goog