[PATCH 07/12] acpi: Ignore acpi_rsdp kernel parameter when securelevel is set

Matthew Garrett
2013-09-09T15:52:23Z

From: Josh Boyer <jwboyer@redhat.com>

This option allows userspace to pass the RSDP address to the kernel, which
makes it possible for a user to execute arbitrary code in the kernel.
Disable this when securelevel is set.

Signed-off-by: Josh Boyer <jwboyer@redhat.com>
---
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 e5f416c..f6d8977 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -45,6 +45,7 @@
#include <linux/list.h>
#include <linux/jiffies.h>
#include <linux/semaphore.h>
+#include <linux/security.h>

#include <asm/io.h>
#include <asm/uaccess.h>
@@ -249,7 +250,7 @@ early_param("acpi_rsdp", setup_acpi_rsdp);
acpi_physical_address __init acpi_os_get_root_pointer(void)
{
#ifdef CONFIG_KEXEC
- if (acpi_rsdp)
+ if (acpi_rsdp && (get_securelevel <= 0))
return acpi_rsdp;
#endif

--
1.8.3.1