From 3938c85004bbd742c5a8c7e1480ed14c2420cd9d Mon Sep 17 00:00:00 2001
From: Miroslav Rezanina <mrezanin@redhat.com>
Date: Tue, 26 Aug 2014 13:33:14 +0200
Subject: [PATCH 1/6] Enforce stack protector usage

Message-id: <1409059994-2966-1-git-send-email-mrezanin@redhat.com>
Patchwork-id: 60699
O-Subject: [RHEL-7.1 qemu-kvm PATCH] Enforce stack protector usage
Bugzilla: 1064260
RH-Acked-by: Amos Kong <akong@redhat.com>
RH-Acked-by: Jeff Nelson <jenelson@redhat.com>
RH-Acked-by: Fam Zheng <famz@redhat.com>

From: Miroslav Rezanina <mrezanin@redhat.com>

If --enable-stack-protector is used is used, configure script try to use
--fstack-protector-strong. In case it's not supported, --fstack-protector-all
is enabled. If both protectors are not supported, configure does not use
any protector at all without any notification.

This patch reports error when user requests stack protector to be used and
both protector modes are not supported. Behavior is not changed in case
user do not use any of --enable-stack-protector/--disable-stack-protector.

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
[Fix non-POSIX operator in test. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

(cherry picked from commit 3b463a3fa8f7690ffa3ef273993dff349b3a73d3)

Conflicts:
	configure - upstream use -fstack-protector-all as second option
                we used -fstack-protector.
                Updated to upstream behavior

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 configure |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/configure b/configure
index 4552e08..0c666e5 100755
--- a/configure
+++ b/configure
@@ -1303,14 +1303,21 @@ for flag in $gcc_flags; do
 done
 
 if test "$stack_protector" != "no" ; then
-  gcc_flags="-fstack-protector-strong -fstack-protector"
+  gcc_flags="-fstack-protector-strong -fstack-protector-all"
+  sp_on=0
   for flag in $gcc_flags; do
     if compile_prog "-Werror $flag" "" ; then
       QEMU_CFLAGS="$QEMU_CFLAGS $flag"
       LIBTOOLFLAGS="$LIBTOOLFLAGS -Wc,$flag"
+      sp_on=1
       break
     fi
   done
+  if test "$stack_protector" = yes; then
+    if test $sp_on = 0; then
+      error_exit "Stack protector not supported"
+    fi
+  fi
 fi
 
 # Workaround for http://gcc.gnu.org/PR55489.  Happens with -fPIE/-fPIC and
-- 
1.7.1