rpms
/
kernel
2
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

CVE-2014-8134 fix espfix for 32-bit KVM paravirt guests (rhbz 1172765 1172769)

This commit is contained in:
Josh Boyer 2014-12-10 13:48:47 -05:00
parent 680349734e
commit 4bd7109228
2 changed files with 82 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
kernel.spec
View File

@ -756,6 +756,9 @@ Patch25111: 0002-ideapad-laptop-Change-Lenovo-Yoga-2-series-rfkill-ha.patch
# CVE-2014-3690 rhbz 1153322 1155372
Patch26060: x86-kvm-vmx-Preserve-CR4-across-VM-entry.patch
#CVE-2014-8134 rhbz 1172765 1172769
Patch26091: x86-kvm-Clear-paravirt_enabled-on-KVM-guests-for-esp.patch
# END OF PATCH DEFINITIONS
%endif
@ -1454,6 +1457,9 @@ ApplyPatch 0002-ideapad-laptop-Change-Lenovo-Yoga-2-series-rfkill-ha.patch
# CVE-2014-3690 rhbz 1153322 1155372
ApplyPatch x86-kvm-vmx-Preserve-CR4-across-VM-entry.patch
#CVE-2014-8134 rhbz 1172765 1172769
ApplyPatch x86-kvm-Clear-paravirt_enabled-on-KVM-guests-for-esp.patch
# END OF PATCH APPLICATIONS
%endif
@ -2266,6 +2272,9 @@ fi
# and build.
%changelog
* Wed Dec 10 2014 Josh Boyer <jwboyer@fedoraproject.org>
- CVE-2014-8134 fix espfix for 32-bit KVM paravirt guests (rhbz 1172765 1172769)
* Mon Dec 08 2014 Justin M. Forbes <jforbes@fedoraproject.org> - 3.14.26-100
- Linux v3.14.26

73
x86-kvm-Clear-paravirt_enabled-on-KVM-guests-for-esp.patch Normal file
View File

@ -0,0 +1,73 @@
From 0fdb006a5af7f391a6de4ce810aba4af46c427e4 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Fri, 5 Dec 2014 19:03:28 -0800
Subject: [PATCH] x86, kvm: Clear paravirt_enabled on KVM guests for espfix32's
benefit
paravirt_enabled has the following effects:
- Disables the F00F bug workaround warning. There is no F00F bug
workaround any more because Linux's standard IDT handling already
works around the F00F bug, but the warning still exists. This
is only cosmetic, and, in any event, there is no such thing as
KVM on a CPU with the F00F bug.
- Disables 32-bit APM BIOS detection. On a KVM paravirt system,
there should be no APM BIOS anyway.
- Disables tboot. I think that the tboot code should check the
CPUID hypervisor bit directly if it matters.
- paravirt_enabled disables espfix32. espfix32 should *not* be
disabled under KVM paravirt.
The last point is the purpose of this patch. It fixes a leak of the
high 16 bits of the kernel stack address on 32-bit KVM paravirt
guests.
While I'm at it, this removes pv_info setup from kvmclock. That
code seems to serve no purpose.
Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
---
arch/x86/kernel/kvm.c | 9 ++++++++-
arch/x86/kernel/kvmclock.c | 2 --
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 3dd8e2c4d74a..07de51f66deb 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -282,7 +282,14 @@ NOKPROBE_SYMBOL(do_async_page_fault);
static void __init paravirt_ops_setup(void)
{
pv_info.name = "KVM";
- pv_info.paravirt_enabled = 1;
+
+ /*
+ * KVM isn't paravirt in the sense of paravirt_enabled. A KVM
+ * guest kernel works like a bare metal kernel with additional
+ * features, and paravirt_enabled is about features that are
+ * missing.
+ */
+ pv_info.paravirt_enabled = 0;
if (kvm_para_has_feature(KVM_FEATURE_NOP_IO_DELAY))
pv_cpu_ops.io_delay = kvm_io_delay;
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index d9156ceecdff..d4d9a8ad7893 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -263,8 +263,6 @@ void __init kvmclock_init(void)
#endif
kvm_get_preset_lpj();
clocksource_register_hz(&kvm_clock, NSEC_PER_SEC);
- pv_info.paravirt_enabled = 1;
- pv_info.name = "KVM";
if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE_STABLE_BIT))
pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT);
--
2.1.0