From: Matthew Garrett <matthew.garrett@nebula.com>
To: linux-kernel@vger.kernel.org
Cc: linux-efi@vger.kernel.org, linux-security-module@vger.kernel.org,
Matthew Garrett <matthew.garrett@nebula.com>
Subject: [PATCH 07/15] ACPI: Limit access to custom_method
Date: Mon, 28 Jan 2013 11:42:31 -0500 [thread overview]
Message-ID: <1359391359-25783-8-git-send-email-matthew.garrett@nebula.com> (raw)
In-Reply-To: <1359391359-25783-1-git-send-email-matthew.garrett@nebula.com>
It must be impossible for even root to get code executed in kernel context
under a secure boot environment. custom_method effectively allows arbitrary
access to system memory, so it needs to have a capability check here.
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
---
drivers/acpi/custom_method.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c
index 5d42c24..247d58b 100644
--- a/drivers/acpi/custom_method.c
+++ b/drivers/acpi/custom_method.c
@@ -29,6 +29,9 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf,
struct acpi_table_header table;
acpi_status status;
+ if (!capable(CAP_COMPROMISE_KERNEL))
+ return -EPERM;
+
if (!(*ppos)) {
/* parse the table header to get the table length */
if (count <= sizeof(struct acpi_table_header))
--
1.8.0.2
next prev parent reply other threads:[~2013-01-28 16:42 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-28 16:42 [PATCH 00/15] Secure boot policy support Matthew Garrett
2013-01-28 16:42 ` [PATCH 01/15] Secure boot: Add new capability Matthew Garrett
2013-01-28 16:42 ` [PATCH 02/15] SELinux: define mapping for new Secure Boot capability Matthew Garrett
2013-01-28 16:42 ` [PATCH 05/15] PCI: Lock down BAR access in secure boot environments Matthew Garrett
[not found] ` <1359391359-25783-1-git-send-email-matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org>
2013-01-28 16:42 ` [PATCH 03/15] Secure boot: Add a dummy kernel parameter that will switch on Secure Boot mode Matthew Garrett
2013-01-28 16:42 ` [PATCH 04/15] efi: Enable secure boot lockdown automatically when enabled in firmware Matthew Garrett
2013-01-28 16:42 ` [PATCH 06/15] x86: Lock down IO port access in secure boot environments Matthew Garrett
2013-01-28 16:42 ` [PATCH 14/15] MODSIGN: Import certificates from UEFI Secure Boot Matthew Garrett
2013-01-28 16:42 ` [PATCH 15/15] MODSIGN: Always enforce module signing in a Secure Boot environment Matthew Garrett
2013-02-17 19:19 ` [PATCH 00/15] Secure boot policy support Yves-Alexis Perez
2013-01-28 16:42 ` Matthew Garrett [this message]
2013-01-28 16:42 ` [PATCH 08/15] asus-wmi: Restrict debugfs interface Matthew Garrett
2013-01-28 16:42 ` [PATCH 09/15] Restrict /dev/mem and /dev/kmem in secure boot setups Matthew Garrett
2013-01-28 16:42 ` [PATCH 10/15] acpi: Ignore acpi_rsdp kernel parameter in a secure boot environment Matthew Garrett
2013-02-17 9:00 ` Dave Young
[not found] ` <CABqxG0cJGp7UEREvMW49QA0BfDXPsyEbAuMMLZwcHPdUAKT+Dw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-02-20 13:39 ` Josh Boyer
2013-01-28 16:42 ` [PATCH 11/15] Add EFI signature data types Matthew Garrett
2013-01-28 16:42 ` [PATCH 12/15] Add an EFI signature blob parser and key loader Matthew Garrett
2013-01-28 16:42 ` [PATCH 13/15] MODSIGN: Add module certificate blacklist keyring Matthew Garrett
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