| Message ID | 20220224060432.1855897-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 200ed341b8646ea893d5466974d6e107c46237ba |
| Headers | show |
| Series | mips: Implement "current_stack_pointer" | expand |
On Wed, Feb 23, 2022 at 10:04:32PM -0800, Kees Cook wrote: > 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: Kees Cook <keescook@chromium.org> > --- > arch/mips/Kconfig | 1 + > arch/mips/include/asm/thread_info.h | 2 ++ > arch/mips/kernel/irq.c | 3 +-- > arch/mips/lib/uncached.c | 4 +--- > 4 files changed, 5 insertions(+), 5 deletions(-) applied to mips-next. Thomas.
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 058446f01487..6781f87e2218 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -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 diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h index 0b17aaa9e012..4463348d2372 100644 --- a/arch/mips/include/asm/thread_info.h +++ b/arch/mips/include/asm/thread_info.h @@ -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 */ diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c index 5e11582fe308..fc313c49a417 100644 --- a/arch/mips/kernel/irq.c +++ b/arch/mips/kernel/irq.c @@ -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; /* diff --git a/arch/mips/lib/uncached.c b/arch/mips/lib/uncached.c index f80a67c092b6..f8d4ca046c3e 100644 --- a/arch/mips/lib/uncached.c +++ b/arch/mips/lib/uncached.c @@ -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);
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: Kees Cook <keescook@chromium.org> --- arch/mips/Kconfig | 1 + arch/mips/include/asm/thread_info.h | 2 ++ arch/mips/kernel/irq.c | 3 +-- arch/mips/lib/uncached.c | 4 +--- 4 files changed, 5 insertions(+), 5 deletions(-)