123 lines
3.8 KiB
Diff
123 lines
3.8 KiB
Diff
From d6b6a8fa92efd244f759ab8ded4ccaebac2b762c Mon Sep 17 00:00:00 2001
|
|
From: Borislav Petkov <bp@suse.de>
|
|
Date: Tue, 12 Dec 2017 14:39:52 +0100
|
|
Subject: [PATCH 191/241] x86/pti: Add the pti= cmdline option and
|
|
documentation
|
|
MIME-Version: 1.0
|
|
Content-Type: text/plain; charset=UTF-8
|
|
Content-Transfer-Encoding: 8bit
|
|
|
|
CVE-2017-5754
|
|
|
|
Keep the "nopti" optional for traditional reasons.
|
|
|
|
[ tglx: Don't allow force on when running on XEN PV and made 'on'
|
|
printout conditional ]
|
|
|
|
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Signed-off-by: Borislav Petkov <bp@suse.de>
|
|
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
Cc: Andy Lutomirski <luto@kernel.org>
|
|
Cc: Andy Lutomirsky <luto@kernel.org>
|
|
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
|
|
Cc: Borislav Petkov <bp@alien8.de>
|
|
Cc: Brian Gerst <brgerst@gmail.com>
|
|
Cc: Dave Hansen <dave.hansen@intel.com>
|
|
Cc: Dave Hansen <dave.hansen@linux.intel.com>
|
|
Cc: David Laight <David.Laight@aculab.com>
|
|
Cc: Denys Vlasenko <dvlasenk@redhat.com>
|
|
Cc: Eduardo Valentin <eduval@amazon.com>
|
|
Cc: Greg KH <gregkh@linuxfoundation.org>
|
|
Cc: H. Peter Anvin <hpa@zytor.com>
|
|
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
|
|
Cc: Juergen Gross <jgross@suse.com>
|
|
Cc: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Cc: Peter Zijlstra <peterz@infradead.org>
|
|
Cc: Will Deacon <will.deacon@arm.com>
|
|
Cc: aliguori@amazon.com
|
|
Cc: daniel.gruss@iaik.tugraz.at
|
|
Cc: hughd@google.com
|
|
Cc: keescook@google.com
|
|
Link: https://lkml.kernel.org/r/20171212133952.10177-1-bp@alien8.de
|
|
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
(cherry picked from commit 41f4c20b57a4890ea7f56ff8717cc83fefb8d537)
|
|
Signed-off-by: Andy Whitcroft <apw@canonical.com>
|
|
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
|
|
(cherry picked from commit 96d3670fa8f88989fb7c0be5172a1378143f3296)
|
|
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
|
|
---
|
|
Documentation/admin-guide/kernel-parameters.txt | 6 ++++++
|
|
arch/x86/mm/pti.c | 26 ++++++++++++++++++++++++-
|
|
2 files changed, 31 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
|
|
index e2a4608da5d2..b4d2edf316db 100644
|
|
--- a/Documentation/admin-guide/kernel-parameters.txt
|
|
+++ b/Documentation/admin-guide/kernel-parameters.txt
|
|
@@ -3247,6 +3247,12 @@
|
|
pt. [PARIDE]
|
|
See Documentation/blockdev/paride.txt.
|
|
|
|
+ pti= [X86_64]
|
|
+ Control user/kernel address space isolation:
|
|
+ on - enable
|
|
+ off - disable
|
|
+ auto - default setting
|
|
+
|
|
pty.legacy_count=
|
|
[KNL] Number of legacy pty's. Overwrites compiled-in
|
|
default number.
|
|
diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c
|
|
index 375f23a758bc..a13f6b109865 100644
|
|
--- a/arch/x86/mm/pti.c
|
|
+++ b/arch/x86/mm/pti.c
|
|
@@ -54,21 +54,45 @@ static void __init pti_print_if_insecure(const char *reason)
|
|
pr_info("%s\n", reason);
|
|
}
|
|
|
|
+static void __init pti_print_if_secure(const char *reason)
|
|
+{
|
|
+ if (!boot_cpu_has_bug(X86_BUG_CPU_INSECURE))
|
|
+ pr_info("%s\n", reason);
|
|
+}
|
|
+
|
|
void __init pti_check_boottime_disable(void)
|
|
{
|
|
+ char arg[5];
|
|
+ int ret;
|
|
+
|
|
if (hypervisor_is_type(X86_HYPER_XEN_PV)) {
|
|
pti_print_if_insecure("disabled on XEN PV.");
|
|
return;
|
|
}
|
|
|
|
+ ret = cmdline_find_option(boot_command_line, "pti", arg, sizeof(arg));
|
|
+ if (ret > 0) {
|
|
+ if (ret == 3 && !strncmp(arg, "off", 3)) {
|
|
+ pti_print_if_insecure("disabled on command line.");
|
|
+ return;
|
|
+ }
|
|
+ if (ret == 2 && !strncmp(arg, "on", 2)) {
|
|
+ pti_print_if_secure("force enabled on command line.");
|
|
+ goto enable;
|
|
+ }
|
|
+ if (ret == 4 && !strncmp(arg, "auto", 4))
|
|
+ goto autosel;
|
|
+ }
|
|
+
|
|
if (cmdline_find_option_bool(boot_command_line, "nopti")) {
|
|
pti_print_if_insecure("disabled on command line.");
|
|
return;
|
|
}
|
|
|
|
+autosel:
|
|
if (!boot_cpu_has_bug(X86_BUG_CPU_INSECURE))
|
|
return;
|
|
-
|
|
+enable:
|
|
setup_force_cpu_cap(X86_FEATURE_PTI);
|
|
}
|
|
|
|
--
|
|
2.14.2
|
|
|