ARM: kprobes: Decode 16-bit Thumb CBZ and bit manipulation instructions (32818f31) · Commits · 戴 / test

arch/arm/kernel/kprobes-thumb.c

+29 −0

Original line number	Diff line number	Diff line
		@@ -96,6 +96,20 @@ t16_simulate_add_sp_imm(struct kprobe p, struct pt_regs regs)
		regs->ARM_sp += imm * 4;
		}

		static void __kprobes
		t16_simulate_cbz(struct kprobe p, struct pt_regs regs)
		{
		kprobe_opcode_t insn = p->opcode;
		int rn = insn & 0x7;
		kprobe_opcode_t nonzero = regs->uregs[rn] ? insn : ~insn;
		if (nonzero & 0x800) {
		long i = insn & 0x200;
		long imm5 = insn & 0xf8;
		unsigned long pc = thumb_probe_pc(p);
		regs->ARM_pc = pc + (i >> 3) + (imm5 >> 2);
		}
		}

		static unsigned long __kprobes
		t16_emulate_loregs(struct kprobe p, struct pt_regs regs)
		{
		@@ -180,6 +194,21 @@ static const union decode_item t16_table_1011[] = {
		/* SUB (SP minus immediate) 1011 0000 1xxx xxxx */
		DECODE_SIMULATE (0xff00, 0xb000, t16_simulate_add_sp_imm),

		/* CBZ 1011 00x1 xxxx xxxx */
		/* CBNZ 1011 10x1 xxxx xxxx */
		DECODE_SIMULATE (0xf500, 0xb100, t16_simulate_cbz),

		/* SXTH 1011 0010 00xx xxxx */
		/* SXTB 1011 0010 01xx xxxx */
		/* UXTH 1011 0010 10xx xxxx */
		/* UXTB 1011 0010 11xx xxxx */
		/* REV 1011 1010 00xx xxxx */
		/* REV16 1011 1010 01xx xxxx */
		/* ??? 1011 1010 10xx xxxx */
		/* REVSH 1011 1010 11xx xxxx */
		DECODE_REJECT (0xffc0, 0xba80),
		DECODE_EMULATE (0xf500, 0xb000, t16_emulate_loregs_rwflags),

		/*
		* If-Then, and hints
		* 1011 1111 xxxx xxxx