linux-toradex.git/scripts/gcc-x86_32-has-stack-protector.sh, branch v2.6.33.1 Linux kernel for Apalis and Colibri modules stackprotector: fix multi-word cross-builds 2009-02-11T11:17:29+00:00 Ingo Molnar mingo@elte.hu 2009-02-11T11:17:29+00:00 ebd9026d9f8499abc60d82d949bd37f88fe34a41 Stackprotector builds were failing if CROSS_COMPILER was more than a single world (such as when distcc was used) - because the check scripts used $1 instead of $*. Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Stackprotector builds were failing if CROSS_COMPILER was more than
a single world (such as when distcc was used) - because the check
scripts used $1 instead of $*.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86: implement x86_32 stack protector 2009-02-09T23:42:01+00:00 Tejun Heo tj@kernel.org 2009-02-09T13:17:40+00:00 60a5317ff0f42dd313094b88f809f63041568b08 Impact: stack protector for x86_32 Implement stack protector for x86_32. GDT entry 28 is used for it. It's set to point to stack_canary-20 and have the length of 24 bytes. CONFIG_CC_STACKPROTECTOR turns off CONFIG_X86_32_LAZY_GS and sets %gs to the stack canary segment on entry. As %gs is otherwise unused by the kernel, the canary can be anywhere. It's defined as a percpu variable. x86_32 exception handlers take register frame on stack directly as struct pt_regs. With -fstack-protector turned on, gcc copies the whole structure after the stack canary and (of course) doesn't copy back on return thus losing all changed. For now, -fno-stack-protector is added to all files which contain those functions. We definitely need something better. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Impact: stack protector for x86_32

Implement stack protector for x86_32.  GDT entry 28 is used for it.
It's set to point to stack_canary-20 and have the length of 24 bytes.
CONFIG_CC_STACKPROTECTOR turns off CONFIG_X86_32_LAZY_GS and sets %gs
to the stack canary segment on entry.  As %gs is otherwise unused by
the kernel, the canary can be anywhere.  It's defined as a percpu
variable.

x86_32 exception handlers take register frame on stack directly as
struct pt_regs.  With -fstack-protector turned on, gcc copies the
whole structure after the stack canary and (of course) doesn't copy
back on return thus losing all changed.  For now, -fno-stack-protector
is added to all files which contain those functions.  We definitely
need something better.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>