* Re: [PATCH] x86: disable stack-protector for __restore_processor_state()
2009-03-30 21:03 [PATCH] x86: disable stack-protector for __restore_processor_state() Joseph Cihula
@ 2009-04-03 17:30 ` Ingo Molnar
2009-04-03 17:33 ` [tip:x86/urgent] " Joseph Cihula
2009-04-03 17:51 ` Joseph Cihula
2 siblings, 0 replies; 4+ messages in thread
From: Ingo Molnar @ 2009-04-03 17:30 UTC (permalink / raw)
To: Joseph Cihula, Tejun Heo; +Cc: linux-kernel, arjan
* Joseph Cihula <joseph.cihula@intel.com> wrote:
> 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>
ah ... very nice!
applied to tip:x86/urgent, thanks Joseph!
Ingo
^ permalink raw reply [flat|nested] 4+ messages in thread
* [tip:x86/urgent] x86: disable stack-protector for __restore_processor_state()
2009-03-30 21:03 [PATCH] x86: disable stack-protector for __restore_processor_state() Joseph Cihula
2009-04-03 17:30 ` Ingo Molnar
@ 2009-04-03 17:33 ` Joseph Cihula
2009-04-03 17:51 ` Joseph Cihula
2 siblings, 0 replies; 4+ messages in thread
From: Joseph Cihula @ 2009-04-03 17:33 UTC (permalink / raw)
To: linux-tip-commits
Cc: linux-kernel, hpa, mingo, arjan, tj, tglx, joseph.cihula, mingo
Commit-ID: 1f23b77e09be10edb30eb03c1b03879083e3cc72
Gitweb: http://git.kernel.org/tip/1f23b77e09be10edb30eb03c1b03879083e3cc72
Author: Joseph Cihula <joseph.cihula@intel.com>
AuthorDate: Mon, 30 Mar 2009 14:03:01 -0700
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 3 Apr 2009 19:30:23 +0200
x86: disable stack-protector for __restore_processor_state()
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>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Tejun Heo <tj@kernel.org>
LKML-Reference: <49D13385.5060900@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
arch/x86/power/Makefile | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile
index 9ff4d5b..58b32db 100644
--- a/arch/x86/power/Makefile
+++ b/arch/x86/power/Makefile
@@ -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
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [tip:x86/urgent] x86: disable stack-protector for __restore_processor_state()
2009-03-30 21:03 [PATCH] x86: disable stack-protector for __restore_processor_state() Joseph Cihula
2009-04-03 17:30 ` Ingo Molnar
2009-04-03 17:33 ` [tip:x86/urgent] " Joseph Cihula
@ 2009-04-03 17:51 ` Joseph Cihula
2 siblings, 0 replies; 4+ messages in thread
From: Joseph Cihula @ 2009-04-03 17:51 UTC (permalink / raw)
To: linux-tip-commits
Cc: linux-kernel, hpa, mingo, arjan, joseph.cihula, chrisw, tj, tglx,
mingo
Commit-ID: 9b7b89efa3bdaceaa2efb93e2d635391835da209
Gitweb: http://git.kernel.org/tip/9b7b89efa3bdaceaa2efb93e2d635391835da209
Author: Joseph Cihula <joseph.cihula@intel.com>
AuthorDate: Mon, 30 Mar 2009 14:03:01 -0700
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 3 Apr 2009 19:48:41 +0200
x86: disable stack-protector for __restore_processor_state()
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>
Tested-by: Chris Wright <chrisw@sous-sol.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Tejun Heo <tj@kernel.org>
LKML-Reference: <49D13385.5060900@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
arch/x86/power/Makefile | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile
index 9ff4d5b..58b32db 100644
--- a/arch/x86/power/Makefile
+++ b/arch/x86/power/Makefile
@@ -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
^ permalink raw reply related [flat|nested] 4+ messages in thread