lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1393445473-15068-9-git-send-email-matthew.garrett@nebula.com>
Date:	Wed, 26 Feb 2014 15:11:09 -0500
From:	Matthew Garrett <matthew.garrett@...ula.com>
To:	linux-kernel@...r.kernel.org
Cc:	keescook@...omium.org, gregkh@...uxfoundation.org, hpa@...or.com,
	linux-efi@...r.kernel.org, jmorris@...ei.org,
	linux-security-module@...r.kernel.org,
	Matthew Garrett <matthew.garrett@...ula.com>
Subject: [PATCH 08/12] kexec: Disable at runtime if trusted_kernel is true

kexec permits the loading and execution of arbitrary code in ring 0, which
permits the modification of the running kernel. Prevent this if
 trusted_kernel is true.

Signed-off-by: Matthew Garrett <matthew.garrett@...ula.com>
---
 kernel/kexec.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 60bafbe..281ddd0 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -32,6 +32,7 @@
 #include <linux/vmalloc.h>
 #include <linux/swap.h>
 #include <linux/syscore_ops.h>
+#include <linux/security.h>
 
 #include <asm/page.h>
 #include <asm/uaccess.h>
@@ -946,6 +947,9 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
 	if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
 		return -EPERM;
 
+	if (get_trusted_kernel())
+		return -EPERM;
+
 	/*
 	 * Verify we have a legal set of flags
 	 * This leaves us room for future extensions.
-- 
1.8.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ