diff options
| -rw-r--r-- | arch/arm/kernel/kprobes.c | 8 | ||||
| -rw-r--r-- | arch/arm/kernel/traps.c | 12 | ||||
| -rw-r--r-- | include/asm-arm/kprobes.h | 7 |
3 files changed, 20 insertions, 7 deletions
diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index 450ee2cbfe17..a22a98c43ca5 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -26,12 +26,6 @@ #include <asm/traps.h> #include <asm/cacheflush.h> -/* - * This undefined instruction must be unique and - * reserved solely for kprobes' use. - */ -#define KPROBE_BREAKPOINT_INSTRUCTION 0xe7f001f8 - #define MIN_STACK_SIZE(addr) \ min((unsigned long)MAX_STACK_SIZE, \ (unsigned long)current_thread_info() + THREAD_START_SP - (addr)) @@ -206,7 +200,7 @@ void __kprobes kprobe_handler(struct pt_regs *regs) } } -static int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr) +int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr) { kprobe_handler(regs); return 0; diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 65bb762b2d80..5595fdd75e82 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -19,6 +19,7 @@ #include <linux/kallsyms.h> #include <linux/delay.h> #include <linux/init.h> +#include <linux/kprobes.h> #include <asm/atomic.h> #include <asm/cacheflush.h> @@ -313,6 +314,17 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs) get_user(instr, (u32 __user *)pc); } +#ifdef CONFIG_KPROBES + /* + * It is possible to have recursive kprobes, so we can't call + * the kprobe trap handler with the undef_lock held. + */ + if (instr == KPROBE_BREAKPOINT_INSTRUCTION && !user_mode(regs)) { + kprobe_trap_handler(regs, instr); + return; + } +#endif + spin_lock_irqsave(&undef_lock, flags); list_for_each_entry(hook, &undef_hook, node) { if ((instr & hook->instr_mask) == hook->instr_val && diff --git a/include/asm-arm/kprobes.h b/include/asm-arm/kprobes.h index 273f37413ee6..4e7bd32288ae 100644 --- a/include/asm-arm/kprobes.h +++ b/include/asm-arm/kprobes.h @@ -25,6 +25,12 @@ #define MAX_INSN_SIZE 2 #define MAX_STACK_SIZE 64 /* 32 would probably be OK */ +/* + * This undefined instruction must be unique and + * reserved solely for kprobes' use. + */ +#define KPROBE_BREAKPOINT_INSTRUCTION 0xe7f001f8 + #define regs_return_value(regs) ((regs)->ARM_r0) #define flush_insn_slot(p) do { } while (0) #define kretprobe_blacklist_size 0 @@ -55,6 +61,7 @@ struct kprobe_ctlblk { void arch_remove_kprobe(struct kprobe *); +int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr); int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr); int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data); |