671 lines
19 KiB
C
671 lines
19 KiB
C
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/*
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* arch/arm/probes/kprobes/actions-thumb.c
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*
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* Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/ptrace.h>
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#include <linux/kprobes.h>
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#include "../decode-thumb.h"
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#include "core.h"
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#include "checkers.h"
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/* These emulation encodings are functionally equivalent... */
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#define t32_emulate_rd8rn16rm0ra12_noflags \
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t32_emulate_rdlo12rdhi8rn16rm0_noflags
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/* t32 thumb actions */
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static void __kprobes
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t32_simulate_table_branch(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long pc = regs->ARM_pc;
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int rn = (insn >> 16) & 0xf;
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int rm = insn & 0xf;
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unsigned long rnv = (rn == 15) ? pc : regs->uregs[rn];
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unsigned long rmv = regs->uregs[rm];
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unsigned int halfwords;
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if (insn & 0x10) /* TBH */
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halfwords = ((u16 *)rnv)[rmv];
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else /* TBB */
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halfwords = ((u8 *)rnv)[rmv];
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regs->ARM_pc = pc + 2 * halfwords;
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}
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static void __kprobes
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t32_simulate_mrs(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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int rd = (insn >> 8) & 0xf;
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unsigned long mask = 0xf8ff03df; /* Mask out execution state */
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regs->uregs[rd] = regs->ARM_cpsr & mask;
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}
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static void __kprobes
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t32_simulate_cond_branch(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long pc = regs->ARM_pc;
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long offset = insn & 0x7ff; /* imm11 */
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offset += (insn & 0x003f0000) >> 5; /* imm6 */
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offset += (insn & 0x00002000) << 4; /* J1 */
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offset += (insn & 0x00000800) << 7; /* J2 */
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offset -= (insn & 0x04000000) >> 7; /* Apply sign bit */
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regs->ARM_pc = pc + (offset * 2);
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}
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static enum probes_insn __kprobes
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t32_decode_cond_branch(probes_opcode_t insn, struct arch_probes_insn *asi,
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const struct decode_header *d)
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{
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int cc = (insn >> 22) & 0xf;
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asi->insn_check_cc = probes_condition_checks[cc];
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asi->insn_handler = t32_simulate_cond_branch;
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return INSN_GOOD_NO_SLOT;
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}
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static void __kprobes
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t32_simulate_branch(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long pc = regs->ARM_pc;
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long offset = insn & 0x7ff; /* imm11 */
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offset += (insn & 0x03ff0000) >> 5; /* imm10 */
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offset += (insn & 0x00002000) << 9; /* J1 */
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offset += (insn & 0x00000800) << 10; /* J2 */
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if (insn & 0x04000000)
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offset -= 0x00800000; /* Apply sign bit */
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else
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offset ^= 0x00600000; /* Invert J1 and J2 */
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if (insn & (1 << 14)) {
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/* BL or BLX */
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regs->ARM_lr = regs->ARM_pc | 1;
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if (!(insn & (1 << 12))) {
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/* BLX so switch to ARM mode */
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regs->ARM_cpsr &= ~PSR_T_BIT;
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pc &= ~3;
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}
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}
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regs->ARM_pc = pc + (offset * 2);
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}
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static void __kprobes
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t32_simulate_ldr_literal(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long addr = regs->ARM_pc & ~3;
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int rt = (insn >> 12) & 0xf;
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unsigned long rtv;
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long offset = insn & 0xfff;
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if (insn & 0x00800000)
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addr += offset;
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else
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addr -= offset;
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if (insn & 0x00400000) {
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/* LDR */
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rtv = *(unsigned long *)addr;
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if (rt == 15) {
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bx_write_pc(rtv, regs);
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return;
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}
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} else if (insn & 0x00200000) {
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/* LDRH */
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if (insn & 0x01000000)
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rtv = *(s16 *)addr;
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else
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rtv = *(u16 *)addr;
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} else {
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/* LDRB */
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if (insn & 0x01000000)
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rtv = *(s8 *)addr;
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else
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rtv = *(u8 *)addr;
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}
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regs->uregs[rt] = rtv;
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}
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static enum probes_insn __kprobes
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t32_decode_ldmstm(probes_opcode_t insn, struct arch_probes_insn *asi,
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const struct decode_header *d)
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{
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enum probes_insn ret = kprobe_decode_ldmstm(insn, asi, d);
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/* Fixup modified instruction to have halfwords in correct order...*/
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insn = __mem_to_opcode_arm(asi->insn[0]);
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((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(insn >> 16);
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((u16 *)asi->insn)[1] = __opcode_to_mem_thumb16(insn & 0xffff);
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return ret;
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}
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static void __kprobes
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t32_emulate_ldrdstrd(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long pc = regs->ARM_pc & ~3;
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int rt1 = (insn >> 12) & 0xf;
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int rt2 = (insn >> 8) & 0xf;
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int rn = (insn >> 16) & 0xf;
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register unsigned long rt1v asm("r0") = regs->uregs[rt1];
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register unsigned long rt2v asm("r1") = regs->uregs[rt2];
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register unsigned long rnv asm("r2") = (rn == 15) ? pc
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: regs->uregs[rn];
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__asm__ __volatile__ (
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"blx %[fn]"
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: "=r" (rt1v), "=r" (rt2v), "=r" (rnv)
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: "0" (rt1v), "1" (rt2v), "2" (rnv), [fn] "r" (asi->insn_fn)
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: "lr", "memory", "cc"
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);
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if (rn != 15)
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regs->uregs[rn] = rnv; /* Writeback base register */
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regs->uregs[rt1] = rt1v;
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regs->uregs[rt2] = rt2v;
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}
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static void __kprobes
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t32_emulate_ldrstr(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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int rt = (insn >> 12) & 0xf;
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int rn = (insn >> 16) & 0xf;
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int rm = insn & 0xf;
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register unsigned long rtv asm("r0") = regs->uregs[rt];
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register unsigned long rnv asm("r2") = regs->uregs[rn];
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register unsigned long rmv asm("r3") = regs->uregs[rm];
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__asm__ __volatile__ (
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"blx %[fn]"
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: "=r" (rtv), "=r" (rnv)
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: "0" (rtv), "1" (rnv), "r" (rmv), [fn] "r" (asi->insn_fn)
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: "lr", "memory", "cc"
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);
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regs->uregs[rn] = rnv; /* Writeback base register */
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if (rt == 15) /* Can't be true for a STR as they aren't allowed */
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bx_write_pc(rtv, regs);
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else
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regs->uregs[rt] = rtv;
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}
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static void __kprobes
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t32_emulate_rd8rn16rm0_rwflags(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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int rd = (insn >> 8) & 0xf;
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int rn = (insn >> 16) & 0xf;
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int rm = insn & 0xf;
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register unsigned long rdv asm("r1") = regs->uregs[rd];
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register unsigned long rnv asm("r2") = regs->uregs[rn];
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register unsigned long rmv asm("r3") = regs->uregs[rm];
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unsigned long cpsr = regs->ARM_cpsr;
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__asm__ __volatile__ (
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"msr cpsr_fs, %[cpsr] \n\t"
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"blx %[fn] \n\t"
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"mrs %[cpsr], cpsr \n\t"
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: "=r" (rdv), [cpsr] "=r" (cpsr)
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: "0" (rdv), "r" (rnv), "r" (rmv),
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"1" (cpsr), [fn] "r" (asi->insn_fn)
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: "lr", "memory", "cc"
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);
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regs->uregs[rd] = rdv;
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regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
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}
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static void __kprobes
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t32_emulate_rd8pc16_noflags(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long pc = regs->ARM_pc;
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int rd = (insn >> 8) & 0xf;
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register unsigned long rdv asm("r1") = regs->uregs[rd];
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register unsigned long rnv asm("r2") = pc & ~3;
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__asm__ __volatile__ (
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"blx %[fn]"
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: "=r" (rdv)
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: "0" (rdv), "r" (rnv), [fn] "r" (asi->insn_fn)
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: "lr", "memory", "cc"
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);
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regs->uregs[rd] = rdv;
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}
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static void __kprobes
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t32_emulate_rd8rn16_noflags(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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int rd = (insn >> 8) & 0xf;
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int rn = (insn >> 16) & 0xf;
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register unsigned long rdv asm("r1") = regs->uregs[rd];
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register unsigned long rnv asm("r2") = regs->uregs[rn];
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__asm__ __volatile__ (
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"blx %[fn]"
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: "=r" (rdv)
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: "0" (rdv), "r" (rnv), [fn] "r" (asi->insn_fn)
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: "lr", "memory", "cc"
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);
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regs->uregs[rd] = rdv;
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}
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static void __kprobes
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t32_emulate_rdlo12rdhi8rn16rm0_noflags(probes_opcode_t insn,
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struct arch_probes_insn *asi,
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struct pt_regs *regs)
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{
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int rdlo = (insn >> 12) & 0xf;
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int rdhi = (insn >> 8) & 0xf;
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int rn = (insn >> 16) & 0xf;
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int rm = insn & 0xf;
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register unsigned long rdlov asm("r0") = regs->uregs[rdlo];
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register unsigned long rdhiv asm("r1") = regs->uregs[rdhi];
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register unsigned long rnv asm("r2") = regs->uregs[rn];
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register unsigned long rmv asm("r3") = regs->uregs[rm];
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__asm__ __volatile__ (
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"blx %[fn]"
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: "=r" (rdlov), "=r" (rdhiv)
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: "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv),
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[fn] "r" (asi->insn_fn)
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: "lr", "memory", "cc"
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);
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regs->uregs[rdlo] = rdlov;
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regs->uregs[rdhi] = rdhiv;
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}
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/* t16 thumb actions */
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static void __kprobes
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t16_simulate_bxblx(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long pc = regs->ARM_pc + 2;
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int rm = (insn >> 3) & 0xf;
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unsigned long rmv = (rm == 15) ? pc : regs->uregs[rm];
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if (insn & (1 << 7)) /* BLX ? */
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regs->ARM_lr = regs->ARM_pc | 1;
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bx_write_pc(rmv, regs);
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}
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static void __kprobes
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t16_simulate_ldr_literal(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long *base = (unsigned long *)((regs->ARM_pc + 2) & ~3);
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long index = insn & 0xff;
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int rt = (insn >> 8) & 0x7;
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regs->uregs[rt] = base[index];
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}
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static void __kprobes
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t16_simulate_ldrstr_sp_relative(probes_opcode_t insn,
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struct arch_probes_insn *asi, struct pt_regs *regs)
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{
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unsigned long* base = (unsigned long *)regs->ARM_sp;
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long index = insn & 0xff;
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int rt = (insn >> 8) & 0x7;
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if (insn & 0x800) /* LDR */
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regs->uregs[rt] = base[index];
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else /* STR */
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base[index] = regs->uregs[rt];
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}
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static void __kprobes
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t16_simulate_reladr(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
unsigned long base = (insn & 0x800) ? regs->ARM_sp
|
||
|
|
: ((regs->ARM_pc + 2) & ~3);
|
||
|
|
long offset = insn & 0xff;
|
||
|
|
int rt = (insn >> 8) & 0x7;
|
||
|
|
regs->uregs[rt] = base + offset * 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_simulate_add_sp_imm(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
long imm = insn & 0x7f;
|
||
|
|
if (insn & 0x80) /* SUB */
|
||
|
|
regs->ARM_sp -= imm * 4;
|
||
|
|
else /* ADD */
|
||
|
|
regs->ARM_sp += imm * 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_simulate_cbz(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
int rn = insn & 0x7;
|
||
|
|
probes_opcode_t nonzero = regs->uregs[rn] ? insn : ~insn;
|
||
|
|
if (nonzero & 0x800) {
|
||
|
|
long i = insn & 0x200;
|
||
|
|
long imm5 = insn & 0xf8;
|
||
|
|
unsigned long pc = regs->ARM_pc + 2;
|
||
|
|
regs->ARM_pc = pc + (i >> 3) + (imm5 >> 2);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_simulate_it(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* The 8 IT state bits are split into two parts in CPSR:
|
||
|
|
* ITSTATE<1:0> are in CPSR<26:25>
|
||
|
|
* ITSTATE<7:2> are in CPSR<15:10>
|
||
|
|
* The new IT state is in the lower byte of insn.
|
||
|
|
*/
|
||
|
|
unsigned long cpsr = regs->ARM_cpsr;
|
||
|
|
cpsr &= ~PSR_IT_MASK;
|
||
|
|
cpsr |= (insn & 0xfc) << 8;
|
||
|
|
cpsr |= (insn & 0x03) << 25;
|
||
|
|
regs->ARM_cpsr = cpsr;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_singlestep_it(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
regs->ARM_pc += 2;
|
||
|
|
t16_simulate_it(insn, asi, regs);
|
||
|
|
}
|
||
|
|
|
||
|
|
static enum probes_insn __kprobes
|
||
|
|
t16_decode_it(probes_opcode_t insn, struct arch_probes_insn *asi,
|
||
|
|
const struct decode_header *d)
|
||
|
|
{
|
||
|
|
asi->insn_singlestep = t16_singlestep_it;
|
||
|
|
return INSN_GOOD_NO_SLOT;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_simulate_cond_branch(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
unsigned long pc = regs->ARM_pc + 2;
|
||
|
|
long offset = insn & 0x7f;
|
||
|
|
offset -= insn & 0x80; /* Apply sign bit */
|
||
|
|
regs->ARM_pc = pc + (offset * 2);
|
||
|
|
}
|
||
|
|
|
||
|
|
static enum probes_insn __kprobes
|
||
|
|
t16_decode_cond_branch(probes_opcode_t insn, struct arch_probes_insn *asi,
|
||
|
|
const struct decode_header *d)
|
||
|
|
{
|
||
|
|
int cc = (insn >> 8) & 0xf;
|
||
|
|
asi->insn_check_cc = probes_condition_checks[cc];
|
||
|
|
asi->insn_handler = t16_simulate_cond_branch;
|
||
|
|
return INSN_GOOD_NO_SLOT;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_simulate_branch(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
unsigned long pc = regs->ARM_pc + 2;
|
||
|
|
long offset = insn & 0x3ff;
|
||
|
|
offset -= insn & 0x400; /* Apply sign bit */
|
||
|
|
regs->ARM_pc = pc + (offset * 2);
|
||
|
|
}
|
||
|
|
|
||
|
|
static unsigned long __kprobes
|
||
|
|
t16_emulate_loregs(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
unsigned long oldcpsr = regs->ARM_cpsr;
|
||
|
|
unsigned long newcpsr;
|
||
|
|
|
||
|
|
__asm__ __volatile__ (
|
||
|
|
"msr cpsr_fs, %[oldcpsr] \n\t"
|
||
|
|
"ldmia %[regs], {r0-r7} \n\t"
|
||
|
|
"blx %[fn] \n\t"
|
||
|
|
"stmia %[regs], {r0-r7} \n\t"
|
||
|
|
"mrs %[newcpsr], cpsr \n\t"
|
||
|
|
: [newcpsr] "=r" (newcpsr)
|
||
|
|
: [oldcpsr] "r" (oldcpsr), [regs] "r" (regs),
|
||
|
|
[fn] "r" (asi->insn_fn)
|
||
|
|
: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
|
||
|
|
"lr", "memory", "cc"
|
||
|
|
);
|
||
|
|
|
||
|
|
return (oldcpsr & ~APSR_MASK) | (newcpsr & APSR_MASK);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_emulate_loregs_rwflags(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
regs->ARM_cpsr = t16_emulate_loregs(insn, asi, regs);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_emulate_loregs_noitrwflags(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
unsigned long cpsr = t16_emulate_loregs(insn, asi, regs);
|
||
|
|
if (!in_it_block(cpsr))
|
||
|
|
regs->ARM_cpsr = cpsr;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_emulate_hiregs(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
unsigned long pc = regs->ARM_pc + 2;
|
||
|
|
int rdn = (insn & 0x7) | ((insn & 0x80) >> 4);
|
||
|
|
int rm = (insn >> 3) & 0xf;
|
||
|
|
|
||
|
|
register unsigned long rdnv asm("r1");
|
||
|
|
register unsigned long rmv asm("r0");
|
||
|
|
unsigned long cpsr = regs->ARM_cpsr;
|
||
|
|
|
||
|
|
rdnv = (rdn == 15) ? pc : regs->uregs[rdn];
|
||
|
|
rmv = (rm == 15) ? pc : regs->uregs[rm];
|
||
|
|
|
||
|
|
__asm__ __volatile__ (
|
||
|
|
"msr cpsr_fs, %[cpsr] \n\t"
|
||
|
|
"blx %[fn] \n\t"
|
||
|
|
"mrs %[cpsr], cpsr \n\t"
|
||
|
|
: "=r" (rdnv), [cpsr] "=r" (cpsr)
|
||
|
|
: "0" (rdnv), "r" (rmv), "1" (cpsr), [fn] "r" (asi->insn_fn)
|
||
|
|
: "lr", "memory", "cc"
|
||
|
|
);
|
||
|
|
|
||
|
|
if (rdn == 15)
|
||
|
|
rdnv &= ~1;
|
||
|
|
|
||
|
|
regs->uregs[rdn] = rdnv;
|
||
|
|
regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
|
||
|
|
}
|
||
|
|
|
||
|
|
static enum probes_insn __kprobes
|
||
|
|
t16_decode_hiregs(probes_opcode_t insn, struct arch_probes_insn *asi,
|
||
|
|
const struct decode_header *d)
|
||
|
|
{
|
||
|
|
insn &= ~0x00ff;
|
||
|
|
insn |= 0x001; /* Set Rdn = R1 and Rm = R0 */
|
||
|
|
((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(insn);
|
||
|
|
asi->insn_handler = t16_emulate_hiregs;
|
||
|
|
return INSN_GOOD;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_emulate_push(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
__asm__ __volatile__ (
|
||
|
|
"ldr r9, [%[regs], #13*4] \n\t"
|
||
|
|
"ldr r8, [%[regs], #14*4] \n\t"
|
||
|
|
"ldmia %[regs], {r0-r7} \n\t"
|
||
|
|
"blx %[fn] \n\t"
|
||
|
|
"str r9, [%[regs], #13*4] \n\t"
|
||
|
|
:
|
||
|
|
: [regs] "r" (regs), [fn] "r" (asi->insn_fn)
|
||
|
|
: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9",
|
||
|
|
"lr", "memory", "cc"
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
static enum probes_insn __kprobes
|
||
|
|
t16_decode_push(probes_opcode_t insn, struct arch_probes_insn *asi,
|
||
|
|
const struct decode_header *d)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* To simulate a PUSH we use a Thumb-2 "STMDB R9!, {registers}"
|
||
|
|
* and call it with R9=SP and LR in the register list represented
|
||
|
|
* by R8.
|
||
|
|
*/
|
||
|
|
/* 1st half STMDB R9!,{} */
|
||
|
|
((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(0xe929);
|
||
|
|
/* 2nd half (register list) */
|
||
|
|
((u16 *)asi->insn)[1] = __opcode_to_mem_thumb16(insn & 0x1ff);
|
||
|
|
asi->insn_handler = t16_emulate_push;
|
||
|
|
return INSN_GOOD;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_emulate_pop_nopc(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
__asm__ __volatile__ (
|
||
|
|
"ldr r9, [%[regs], #13*4] \n\t"
|
||
|
|
"ldmia %[regs], {r0-r7} \n\t"
|
||
|
|
"blx %[fn] \n\t"
|
||
|
|
"stmia %[regs], {r0-r7} \n\t"
|
||
|
|
"str r9, [%[regs], #13*4] \n\t"
|
||
|
|
:
|
||
|
|
: [regs] "r" (regs), [fn] "r" (asi->insn_fn)
|
||
|
|
: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9",
|
||
|
|
"lr", "memory", "cc"
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __kprobes
|
||
|
|
t16_emulate_pop_pc(probes_opcode_t insn,
|
||
|
|
struct arch_probes_insn *asi, struct pt_regs *regs)
|
||
|
|
{
|
||
|
|
register unsigned long pc asm("r8");
|
||
|
|
|
||
|
|
__asm__ __volatile__ (
|
||
|
|
"ldr r9, [%[regs], #13*4] \n\t"
|
||
|
|
"ldmia %[regs], {r0-r7} \n\t"
|
||
|
|
"blx %[fn] \n\t"
|
||
|
|
"stmia %[regs], {r0-r7} \n\t"
|
||
|
|
"str r9, [%[regs], #13*4] \n\t"
|
||
|
|
: "=r" (pc)
|
||
|
|
: [regs] "r" (regs), [fn] "r" (asi->insn_fn)
|
||
|
|
: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9",
|
||
|
|
"lr", "memory", "cc"
|
||
|
|
);
|
||
|
|
|
||
|
|
bx_write_pc(pc, regs);
|
||
|
|
}
|
||
|
|
|
||
|
|
static enum probes_insn __kprobes
|
||
|
|
t16_decode_pop(probes_opcode_t insn, struct arch_probes_insn *asi,
|
||
|
|
const struct decode_header *d)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* To simulate a POP we use a Thumb-2 "LDMDB R9!, {registers}"
|
||
|
|
* and call it with R9=SP and PC in the register list represented
|
||
|
|
* by R8.
|
||
|
|
*/
|
||
|
|
/* 1st half LDMIA R9!,{} */
|
||
|
|
((u16 *)asi->insn)[0] = __opcode_to_mem_thumb16(0xe8b9);
|
||
|
|
/* 2nd half (register list) */
|
||
|
|
((u16 *)asi->insn)[1] = __opcode_to_mem_thumb16(insn & 0x1ff);
|
||
|
|
asi->insn_handler = insn & 0x100 ? t16_emulate_pop_pc
|
||
|
|
: t16_emulate_pop_nopc;
|
||
|
|
return INSN_GOOD;
|
||
|
|
}
|
||
|
|
|
||
|
|
const union decode_action kprobes_t16_actions[NUM_PROBES_T16_ACTIONS] = {
|
||
|
|
[PROBES_T16_ADD_SP] = {.handler = t16_simulate_add_sp_imm},
|
||
|
|
[PROBES_T16_CBZ] = {.handler = t16_simulate_cbz},
|
||
|
|
[PROBES_T16_SIGN_EXTEND] = {.handler = t16_emulate_loregs_rwflags},
|
||
|
|
[PROBES_T16_PUSH] = {.decoder = t16_decode_push},
|
||
|
|
[PROBES_T16_POP] = {.decoder = t16_decode_pop},
|
||
|
|
[PROBES_T16_SEV] = {.handler = probes_emulate_none},
|
||
|
|
[PROBES_T16_WFE] = {.handler = probes_simulate_nop},
|
||
|
|
[PROBES_T16_IT] = {.decoder = t16_decode_it},
|
||
|
|
[PROBES_T16_CMP] = {.handler = t16_emulate_loregs_rwflags},
|
||
|
|
[PROBES_T16_ADDSUB] = {.handler = t16_emulate_loregs_noitrwflags},
|
||
|
|
[PROBES_T16_LOGICAL] = {.handler = t16_emulate_loregs_noitrwflags},
|
||
|
|
[PROBES_T16_LDR_LIT] = {.handler = t16_simulate_ldr_literal},
|
||
|
|
[PROBES_T16_BLX] = {.handler = t16_simulate_bxblx},
|
||
|
|
[PROBES_T16_HIREGOPS] = {.decoder = t16_decode_hiregs},
|
||
|
|
[PROBES_T16_LDRHSTRH] = {.handler = t16_emulate_loregs_rwflags},
|
||
|
|
[PROBES_T16_LDRSTR] = {.handler = t16_simulate_ldrstr_sp_relative},
|
||
|
|
[PROBES_T16_ADR] = {.handler = t16_simulate_reladr},
|
||
|
|
[PROBES_T16_LDMSTM] = {.handler = t16_emulate_loregs_rwflags},
|
||
|
|
[PROBES_T16_BRANCH_COND] = {.decoder = t16_decode_cond_branch},
|
||
|
|
[PROBES_T16_BRANCH] = {.handler = t16_simulate_branch},
|
||
|
|
};
|
||
|
|
|
||
|
|
const union decode_action kprobes_t32_actions[NUM_PROBES_T32_ACTIONS] = {
|
||
|
|
[PROBES_T32_LDMSTM] = {.decoder = t32_decode_ldmstm},
|
||
|
|
[PROBES_T32_LDRDSTRD] = {.handler = t32_emulate_ldrdstrd},
|
||
|
|
[PROBES_T32_TABLE_BRANCH] = {.handler = t32_simulate_table_branch},
|
||
|
|
[PROBES_T32_TST] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_MOV] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_ADDSUB] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_LOGICAL] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_CMP] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_ADDWSUBW_PC] = {.handler = t32_emulate_rd8pc16_noflags,},
|
||
|
|
[PROBES_T32_ADDWSUBW] = {.handler = t32_emulate_rd8rn16_noflags},
|
||
|
|
[PROBES_T32_MOVW] = {.handler = t32_emulate_rd8rn16_noflags},
|
||
|
|
[PROBES_T32_SAT] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_BITFIELD] = {.handler = t32_emulate_rd8rn16_noflags},
|
||
|
|
[PROBES_T32_SEV] = {.handler = probes_emulate_none},
|
||
|
|
[PROBES_T32_WFE] = {.handler = probes_simulate_nop},
|
||
|
|
[PROBES_T32_MRS] = {.handler = t32_simulate_mrs},
|
||
|
|
[PROBES_T32_BRANCH_COND] = {.decoder = t32_decode_cond_branch},
|
||
|
|
[PROBES_T32_BRANCH] = {.handler = t32_simulate_branch},
|
||
|
|
[PROBES_T32_PLDI] = {.handler = probes_simulate_nop},
|
||
|
|
[PROBES_T32_LDR_LIT] = {.handler = t32_simulate_ldr_literal},
|
||
|
|
[PROBES_T32_LDRSTR] = {.handler = t32_emulate_ldrstr},
|
||
|
|
[PROBES_T32_SIGN_EXTEND] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_MEDIA] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_REVERSE] = {.handler = t32_emulate_rd8rn16_noflags},
|
||
|
|
[PROBES_T32_MUL_ADD] = {.handler = t32_emulate_rd8rn16rm0_rwflags},
|
||
|
|
[PROBES_T32_MUL_ADD2] = {.handler = t32_emulate_rd8rn16rm0ra12_noflags},
|
||
|
|
[PROBES_T32_MUL_ADD_LONG] = {
|
||
|
|
.handler = t32_emulate_rdlo12rdhi8rn16rm0_noflags},
|
||
|
|
};
|
||
|
|
|
||
|
|
const struct decode_checker *kprobes_t32_checkers[] = {t32_stack_checker, NULL};
|
||
|
|
const struct decode_checker *kprobes_t16_checkers[] = {t16_stack_checker, NULL};
|