From: Joseph Cihula <joseph.cihula@intel.com>
To: linux-kernel@vger.kernel.org, arjan@linux.intel.com, mingo@elte.hu
Subject: [PATCH] x86: disable stack-protector for __restore_processor_state()
Date: Mon, 30 Mar 2009 14:03:01 -0700 [thread overview]
Message-ID: <49D13385.5060900@intel.com> (raw)
The __restore_processor_state() fn restores %gs on resume from S3. As
such, it cannot be protected by the stack-protector guard since %gs will
not be correct on function entry.
There are only a few other fns in this file and it should not negatively
impact kernel security that they will also have the stack-protector
guard removed (and so it's not worth moving them to another file).
Without this change, S3 resume on a kernel built with
CONFIG_CC_STACKPROTECTOR_ALL=y will fail.
Signed-off-by: Joseph Cihula <joseph.cihula@intel.com>
--- ../linux.trees.git/arch/x86/power/Makefile 2009-03-29
12:12:13.000000000 -0700
+++ arch/x86/power/Makefile 2009-03-30 12:21:19.000000000 -0700
@@ -1,2 +1,7 @@
+# __restore_processor_state() restores %gs after S3 resume and so
should not
+# itself be stack-protected
+nostackp := $(call cc-option, -fno-stack-protector)
+CFLAGS_cpu_$(BITS).o := $(nostackp)
+
obj-$(CONFIG_PM_SLEEP) += cpu_$(BITS).o
obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o
next reply other threads:[~2009-03-30 21:03 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-30 21:03 Joseph Cihula [this message]
2009-04-03 17:30 ` [PATCH] x86: disable stack-protector for __restore_processor_state() Ingo Molnar
2009-04-03 17:33 ` [tip:x86/urgent] " Joseph Cihula
2009-04-03 17:51 ` Joseph Cihula
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=49D13385.5060900@intel.com \
--to=joseph.cihula@intel.com \
--cc=arjan@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.