Ejemplo n.º 1
0
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
	unsigned int brkp;
	void *addr;

	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
		/* Remove any Thumb flag */
		addr = (void *)((uintptr_t)p->addr & ~1);

		if (is_wide_instruction(p->opcode))
			brkp = KPROBE_THUMB32_BREAKPOINT_INSTRUCTION;
		else
			brkp = KPROBE_THUMB16_BREAKPOINT_INSTRUCTION;
	} else {
		kprobe_opcode_t insn = p->opcode;

		addr = p->addr;
		brkp = KPROBE_ARM_BREAKPOINT_INSTRUCTION;

		if (insn >= 0xe0000000)
			brkp |= 0xe0000000;  /* Unconditional instruction */
		else
			brkp |= insn & 0xf0000000;  /* Copy condition from insn */
	}

	patch_text(addr, brkp);
}
Ejemplo n.º 2
0
int __kprobes arch_prepare_kprobe(struct kprobe *p)
{
	kprobe_opcode_t insn;
	kprobe_opcode_t tmp_insn[MAX_INSN_SIZE];
	unsigned long addr = (unsigned long)p->addr;
	bool thumb;
	kprobe_decode_insn_t *decode_insn;
	int is;

	if (in_exception_text(addr))
		return -EINVAL;

#ifdef CONFIG_THUMB2_KERNEL
	thumb = true;
	addr &= ~1; /* Bit 0 would normally be set to indicate Thumb code */
	insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]);
	if (is_wide_instruction(insn)) {
		u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]);
		insn = __opcode_thumb32_compose(insn, inst2);
		decode_insn = thumb32_kprobe_decode_insn;
	} else
		decode_insn = thumb16_kprobe_decode_insn;
#else /* !CONFIG_THUMB2_KERNEL */
	thumb = false;
	if (addr & 0x3)
		return -EINVAL;
	insn = __mem_to_opcode_arm(*p->addr);
	decode_insn = arm_kprobe_decode_insn;
#endif

	p->opcode = insn;
	p->ainsn.insn = tmp_insn;

	switch ((*decode_insn)(insn, &p->ainsn)) {
	case INSN_REJECTED:	/* not supported */
		return -EINVAL;

	case INSN_GOOD:		/* instruction uses slot */
		p->ainsn.insn = get_insn_slot();
		if (!p->ainsn.insn)
			return -ENOMEM;
		for (is = 0; is < MAX_INSN_SIZE; ++is)
			p->ainsn.insn[is] = tmp_insn[is];
		flush_insns(p->ainsn.insn,
				sizeof(p->ainsn.insn[0]) * MAX_INSN_SIZE);
		p->ainsn.insn_fn = (kprobe_insn_fn_t *)
					((uintptr_t)p->ainsn.insn | thumb);
		break;

	case INSN_GOOD_NO_SLOT:	/* instruction doesn't need insn slot */
		p->ainsn.insn = NULL;
		break;
	}

	return 0;
}
Ejemplo n.º 3
0
static void __kprobes
singlestep_skip(struct kprobe *p, struct pt_regs *regs)
{
#ifdef CONFIG_THUMB2_KERNEL
	regs->ARM_cpsr = it_advance(regs->ARM_cpsr);
	if (is_wide_instruction(p->opcode))
		regs->ARM_pc += 4;
	else
		regs->ARM_pc += 2;
#else
	regs->ARM_pc += 4;
#endif
}
Ejemplo n.º 4
0
asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
{
	u32 instr;
	siginfo_t info;
	void __user *pc = (void __user *)instruction_pointer(regs);
	struct thread_info *thread = current_thread_info();

	/* check for AArch32 breakpoint instructions */
	if (!aarch32_break_handler(regs))
		return;
	if (user_mode(regs)) {
		if (compat_thumb_mode(regs)) {
			if (get_user(instr, (u16 __user *)pc))
				goto die_sig;
			if (is_wide_instruction(instr)) {
				u32 instr2;
				if (get_user(instr2, (u16 __user *)pc+1))
					goto die_sig;
				instr <<= 16;
				instr |= instr2;
			}
		} else if (get_user(instr, (u32 __user *)pc)) {
			goto die_sig;
		}
	} else {
		/* kernel mode */
		instr = *((u32 *)pc);
	}

	if (call_undef_hook(regs, instr) == 0)
		return;

die_sig:
	if (show_unhandled_signals && unhandled_signal(current, SIGILL) &&
	    printk_ratelimit()) {
		pr_info("%s[%d]: undefined instruction: pc=%p\n",
			current->comm, task_pid_nr(current), pc);
		dump_instr(KERN_INFO, regs);
	}

	info.si_signo = SIGILL;
	info.si_errno = 0;
	info.si_code  = ILL_ILLOPC;
	info.si_addr  = pc;

	arm64_notify_die("Oops - undefined instruction", regs, &info, 0);
}
Ejemplo n.º 5
0
int __kprobes arch_prepare_kprobe(struct kprobe *p)
{
	kprobe_opcode_t insn;
	kprobe_opcode_t tmp_insn[MAX_INSN_SIZE];
	unsigned long addr = (unsigned long)p->addr;
	bool thumb;
	kprobe_decode_insn_t *decode_insn;
	const union decode_action *actions;
	int is;
	const struct decode_checker **checkers;

	if (in_exception_text(addr))
		return -EINVAL;

#ifdef CONFIG_THUMB2_KERNEL
	thumb = true;
	addr &= ~1; /* Bit 0 would normally be set to indicate Thumb code */
	insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]);
	if (is_wide_instruction(insn)) {
		u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]);
		insn = __opcode_thumb32_compose(insn, inst2);
		decode_insn = thumb32_probes_decode_insn;
		actions = kprobes_t32_actions;
		checkers = kprobes_t32_checkers;
	} else {
		decode_insn = thumb16_probes_decode_insn;
		actions = kprobes_t16_actions;
		checkers = kprobes_t16_checkers;
	}
#else /* !CONFIG_THUMB2_KERNEL */
	thumb = false;
	if (addr & 0x3)
		return -EINVAL;
	insn = __mem_to_opcode_arm(*p->addr);
	decode_insn = arm_probes_decode_insn;
	actions = kprobes_arm_actions;
	checkers = kprobes_arm_checkers;
#endif

	p->opcode = insn;
	p->ainsn.insn = tmp_insn;

	switch ((*decode_insn)(insn, &p->ainsn, true, actions, checkers)) {
	case INSN_REJECTED:	/* not supported */
		return -EINVAL;

	case INSN_GOOD:		/* instruction uses slot */
		p->ainsn.insn = get_insn_slot();
		if (!p->ainsn.insn)
			return -ENOMEM;
		for (is = 0; is < MAX_INSN_SIZE; ++is)
			p->ainsn.insn[is] = tmp_insn[is];
		flush_insns(p->ainsn.insn,
				sizeof(p->ainsn.insn[0]) * MAX_INSN_SIZE);
		p->ainsn.insn_fn = (probes_insn_fn_t *)
					((uintptr_t)p->ainsn.insn | thumb);
		break;

	case INSN_GOOD_NO_SLOT:	/* instruction doesn't need insn slot */
		p->ainsn.insn = NULL;
		break;
	}

	/*
	 * Never instrument insn like 'str r0, [sp, +/-r1]'. Also, insn likes
	 * 'str r0, [sp, #-68]' should also be prohibited.
	 * See __und_svc.
	 */
	if ((p->ainsn.stack_space < 0) ||
			(p->ainsn.stack_space > MAX_STACK_SIZE))
		return -EINVAL;

	return 0;
}