From 0d73c3f8e7f6ee2aab1bb350f60c180f5ae21a2c Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Sun, 13 May 2018 05:04:29 +0100 Subject: ARM: 8772/1: kprobes: Prohibit kprobes on get_user functions Since do_undefinstr() uses get_user to get the undefined instruction, it can be called before kprobes processes recursive check. This can cause an infinit recursive exception. Prohibit probing on get_user functions. Fixes: 24ba613c9d6c ("ARM kprobes: core code") Signed-off-by: Masami Hiramatsu Cc: stable@vger.kernel.org Signed-off-by: Russell King --- arch/arm/include/asm/assembler.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/arm/include/asm/assembler.h') diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index bc8d4bbd82e2..9342904cccca 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -536,4 +536,14 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) #endif .endm +#ifdef CONFIG_KPROBES +#define _ASM_NOKPROBE(entry) \ + .pushsection "_kprobe_blacklist", "aw" ; \ + .balign 4 ; \ + .long entry; \ + .popsection +#else +#define _ASM_NOKPROBE(entry) +#endif + #endif /* __ASM_ASSEMBLER_H__ */ -- cgit From a78d156587931a2c3b354534aa772febf6c9e855 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 11 May 2018 11:15:29 +0100 Subject: ARM: spectre-v1: add speculation barrier (csdb) macros Add assembly and C macros for the new CSDB instruction. Signed-off-by: Russell King Acked-by: Mark Rutland Boot-tested-by: Tony Lindgren Reviewed-by: Tony Lindgren --- arch/arm/include/asm/assembler.h | 8 ++++++++ arch/arm/include/asm/barrier.h | 13 +++++++++++++ 2 files changed, 21 insertions(+) (limited to 'arch/arm/include/asm/assembler.h') diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index bc8d4bbd82e2..ef1386b1af9b 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -447,6 +447,14 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) .size \name , . - \name .endm + .macro csdb +#ifdef CONFIG_THUMB2_KERNEL + .inst.w 0xf3af8014 +#else + .inst 0xe320f014 +#endif + .endm + .macro check_uaccess, addr:req, size:req, limit:req, tmp:req, bad:req #ifndef CONFIG_CPU_USE_DOMAINS adds \tmp, \addr, #\size - 1 diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h index 40f5c410fd8c..3d9c1d4b7e75 100644 --- a/arch/arm/include/asm/barrier.h +++ b/arch/arm/include/asm/barrier.h @@ -17,6 +17,12 @@ #define isb(option) __asm__ __volatile__ ("isb " #option : : : "memory") #define dsb(option) __asm__ __volatile__ ("dsb " #option : : : "memory") #define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory") +#ifdef CONFIG_THUMB2_KERNEL +#define CSDB ".inst.w 0xf3af8014" +#else +#define CSDB ".inst 0xe320f014" +#endif +#define csdb() __asm__ __volatile__(CSDB : : : "memory") #elif defined(CONFIG_CPU_XSC3) || __LINUX_ARM_ARCH__ == 6 #define isb(x) __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \ : : "r" (0) : "memory") @@ -37,6 +43,13 @@ #define dmb(x) __asm__ __volatile__ ("" : : : "memory") #endif +#ifndef CSDB +#define CSDB +#endif +#ifndef csdb +#define csdb() +#endif + #ifdef CONFIG_ARM_HEAVY_MB extern void (*soc_mb)(void); extern void arm_heavy_mb(void); -- cgit