From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: [PATCH V31 14/25] acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down Date: Tue, 26 Mar 2019 11:27:30 -0700 Message-ID: <20190326182742.16950-15-matthewgarrett@google.com> References: <20190326182742.16950-1-matthewgarrett@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20190326182742.16950-1-matthewgarrett@google.com> Sender: linux-kernel-owner@vger.kernel.org To: jmorris@namei.org Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-api@vger.kernel.org, luto@kernel.org, Josh Boyer , Matthew Garrett , Dave Young , linux-acpi@vger.kernel.org List-Id: linux-api@vger.kernel.org From: Josh Boyer This option allows userspace to pass the RSDP address to the kernel, which makes it possible for a user to modify the workings of hardware . Reject the option when the kernel is locked down. Signed-off-by: Josh Boyer Signed-off-by: David Howells Signed-off-by: Matthew Garrett cc: Dave Young cc: linux-acpi@vger.kernel.org --- drivers/acpi/osl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index f29e427d0d1d..cd5bba7b8eb3 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -194,7 +194,8 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) acpi_physical_address pa; #ifdef CONFIG_KEXEC - if (acpi_rsdp) + if (acpi_rsdp && !kernel_is_locked_down("ACPI RSDP specification", + LOCKDOWN_INTEGRITY)) return acpi_rsdp; #endif pa = acpi_arch_get_root_pointer(); -- 2.21.0.392.gf8f6787159e-goog