lkml.org 
[lkml]   [2006]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[patch 5/5] -fstack-protector feature: Enable the compiler flags in CFLAGS
From
Date
Subject: [patch 5/5] Add the -fstack-protector option to the CFLAGS
From: Arjan van de Ven <arjan@linux.intel.com>

Add a feature check that checks that the gcc compiler has stack-protector
support and has the bugfix for PR28281 to make this work in kernel mode.
The easiest solution I could find was to have a shell script in scripts/
to do the detection; if needed we can make this fancier in the future
without making the makefile too complex.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
CC: Andi Kleen <ak@suse.de>
CC: Sam Ravnborg <sam@ravnborg.org>

---
arch/x86_64/Makefile | 3 +++
scripts/gcc-x86_64-has-stack-protector.sh | 8 ++++++++
2 files changed, 11 insertions(+)
Index: linux-2.6.18-rc4-stackprot/arch/x86_64/Makefile
===================================================================
--- linux-2.6.18-rc4-stackprot.orig/arch/x86_64/Makefile
+++ linux-2.6.18-rc4-stackprot/arch/x86_64/Makefile
@@ -55,6 +55,9 @@ cflags-y += $(call cc-option,-funit-at-a
# prevent gcc from generating any FP code by mistake
cflags-y += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)

+cflags-$(CONFIG_CC_STACKPROTECTOR) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC) -fstack-protector )
+cflags-$(CONFIG_CC_STACKPROTECTOR_ALL) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC) -fstack-protector-all )
+
CFLAGS += $(cflags-y)
CFLAGS_KERNEL += $(cflags-kernel-y)
AFLAGS += -m64
Index: linux-2.6.18-rc4-stackprot/scripts/gcc-x86_64-has-stack-protector.sh
===================================================================
--- /dev/null
+++ linux-2.6.18-rc4-stackprot/scripts/gcc-x86_64-has-stack-protector.sh
@@ -0,0 +1,6 @@
+#!/bin/sh
+
+echo "int foo(void) { char X[200]; return 3; }" | $1 -S -xc -c -O0 -mcmodel=kernel -fstack-protector - -o - | grep -q "%gs"
+if [ "$?" -eq "0" ] ; then
+ echo $2
+fi
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-08-16 19:15    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site