[PATCH 4.9 118/164] arm: KVM: Do not use stack-protector to compile HYP code

From: Greg Kroah-Hartman
Date: Tue May 23 2017 - 16:31:23 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Marc Zyngier <marc.zyngier@xxxxxxx>

commit 501ad27c67ed0b90df465f23d33e9aed64058a47 upstream.

We like living dangerously. Nothing explicitely forbids stack-protector
to be used in the HYP code, while distributions routinely compile their
kernel with it. We're just lucky that no code actually triggers the
instrumentation.

Let's not try our luck for much longer, and disable stack-protector
for code living at HYP.

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Acked-by: Christoffer Dall <cdall@xxxxxxxxxx>
Signed-off-by: Christoffer Dall <cdall@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm/kvm/hyp/Makefile | 2 ++
1 file changed, 2 insertions(+)

--- a/arch/arm/kvm/hyp/Makefile
+++ b/arch/arm/kvm/hyp/Makefile
@@ -2,6 +2,8 @@
# Makefile for Kernel-based Virtual Machine module, HYP part
#

+ccflags-y += -fno-stack-protector
+
KVM=../../../../virt/kvm

obj-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/hyp/vgic-v2-sr.o