Commit 200ed341 authored by Kees Cook's avatar Kees Cook Committed by Thomas Bogendoerfer
Browse files

mips: Implement "current_stack_pointer" 



To follow the existing per-arch conventions replace open-coded uses
of asm "sp" as "current_stack_pointer". This will let it be used in
non-arch places (like HARDENED_USERCOPY).

Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Yanteng Si <siyanteng01@gmail.com>
Cc: linux-mips@vger.kernel.org
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarThomas Bogendoerfer <tsbogend@alpha.franken.de>
parent 455481fc

arch/mips/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ config MIPS 
	default y

	select ARCH_32BIT_OFF_T if !64BIT

	select ARCH_BINFMT_ELF_STATE if MIPS_FP_SUPPORT

	select ARCH_HAS_CURRENT_STACK_POINTER

	select ARCH_HAS_DEBUG_VIRTUAL if !64BIT

	select ARCH_HAS_FORTIFY_SOURCE

	select ARCH_HAS_KCOV

arch/mips/include/asm/thread_info.h

+2 −0
Original line number Diff line number Diff line
@@ -69,6 +69,8 @@ static inline struct thread_info *current_thread_info(void) 
	return __current_thread_info;

}



register unsigned long current_stack_pointer __asm__("sp");



#endif /* !__ASSEMBLY__ */



/* thread information allocation */

arch/mips/kernel/irq.c

+1 −2
Original line number Diff line number Diff line
@@ -75,9 +75,8 @@ void __init init_IRQ(void) 
#ifdef CONFIG_DEBUG_STACKOVERFLOW

static inline void check_stack_overflow(void)

{

	unsigned long sp;

	unsigned long sp = current_stack_pointer;



	__asm__ __volatile__("move %0, $sp" : "=r" (sp));

	sp &= THREAD_MASK;



	/*

arch/mips/lib/uncached.c

+1 −3
Original line number Diff line number Diff line
@@ -40,9 +40,7 @@ unsigned long run_uncached(void *func) 
	register long ret __asm__("$2");

	long lfunc = (long)func, ufunc;

	long usp;

	long sp;



	__asm__("move %0, $sp" : "=r" (sp));

	long sp = current_stack_pointer;



	if (sp >= (long)CKSEG0 && sp < (long)CKSEG2)

		usp = CKSEG1ADDR(sp);