https://github.com/torvalds/linux
Tip revision: f443e374ae131c168a065ea1748feac6b2e76613 authored by Linus Torvalds on 20 March 2022, 20:14:17 UTC
Linux 5.17
Linux 5.17
Tip revision: f443e37
pf_in.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Fault Injection Test harness (FI)
* Copyright (C) Intel Crop.
*/
/* Id: pf_in.c,v 1.1.1.1 2002/11/12 05:56:32 brlock Exp
* Copyright by Intel Crop., 2002
* Louis Zhuang (louis.zhuang@intel.com)
*
* Bjorn Steinbrink (B.Steinbrink@gmx.de), 2007
*/
#include <linux/ptrace.h> /* struct pt_regs */
#include "pf_in.h"
#ifdef __i386__
/* IA32 Manual 3, 2-1 */
static unsigned char prefix_codes[] = {
0xF0, 0xF2, 0xF3, 0x2E, 0x36, 0x3E, 0x26, 0x64,
0x65, 0x66, 0x67
};
/* IA32 Manual 3, 3-432*/
static unsigned int reg_rop[] = {
0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
};
static unsigned int reg_wop[] = { 0x88, 0x89, 0xAA, 0xAB };
static unsigned int imm_wop[] = { 0xC6, 0xC7 };
/* IA32 Manual 3, 3-432*/
static unsigned int rw8[] = { 0x88, 0x8A, 0xC6, 0xAA };
static unsigned int rw32[] = {
0x89, 0x8B, 0xC7, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F, 0xAB
};
static unsigned int mw8[] = { 0x88, 0x8A, 0xC6, 0xB60F, 0xBE0F, 0xAA };
static unsigned int mw16[] = { 0xB70F, 0xBF0F };
static unsigned int mw32[] = { 0x89, 0x8B, 0xC7, 0xAB };
static unsigned int mw64[] = {};
#else /* not __i386__ */
static unsigned char prefix_codes[] = {
0x66, 0x67, 0x2E, 0x3E, 0x26, 0x64, 0x65, 0x36,
0xF0, 0xF3, 0xF2,
/* REX Prefixes */
0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
};
/* AMD64 Manual 3, Appendix A*/
static unsigned int reg_rop[] = {
0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
};
static unsigned int reg_wop[] = { 0x88, 0x89, 0xAA, 0xAB };
static unsigned int imm_wop[] = { 0xC6, 0xC7 };
static unsigned int rw8[] = { 0xC6, 0x88, 0x8A, 0xAA };
static unsigned int rw32[] = {
0xC7, 0x89, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F, 0xAB
};
/* 8 bit only */
static unsigned int mw8[] = { 0xC6, 0x88, 0x8A, 0xB60F, 0xBE0F, 0xAA };
/* 16 bit only */
static unsigned int mw16[] = { 0xB70F, 0xBF0F };
/* 16 or 32 bit */
static unsigned int mw32[] = { 0xC7 };
/* 16, 32 or 64 bit */
static unsigned int mw64[] = { 0x89, 0x8B, 0xAB };
#endif /* not __i386__ */
struct prefix_bits {
unsigned shorted:1;
unsigned enlarged:1;
unsigned rexr:1;
unsigned rex:1;
};
static int skip_prefix(unsigned char *addr, struct prefix_bits *prf)
{
int i;
unsigned char *p = addr;
prf->shorted = 0;
prf->enlarged = 0;
prf->rexr = 0;
prf->rex = 0;
restart:
for (i = 0; i < ARRAY_SIZE(prefix_codes); i++) {
if (*p == prefix_codes[i]) {
if (*p == 0x66)
prf->shorted = 1;
#ifdef __amd64__
if ((*p & 0xf8) == 0x48)
prf->enlarged = 1;
if ((*p & 0xf4) == 0x44)
prf->rexr = 1;
if ((*p & 0xf0) == 0x40)
prf->rex = 1;
#endif
p++;
goto restart;
}
}
return (p - addr);
}
static int get_opcode(unsigned char *addr, unsigned int *opcode)
{
int len;
if (*addr == 0x0F) {
/* 0x0F is extension instruction */
*opcode = *(unsigned short *)addr;
len = 2;
} else {
*opcode = *addr;
len = 1;
}
return len;
}
#define CHECK_OP_TYPE(opcode, array, type) \
for (i = 0; i < ARRAY_SIZE(array); i++) { \
if (array[i] == opcode) { \
rv = type; \
goto exit; \
} \
}
enum reason_type get_ins_type(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char *p;
struct prefix_bits prf;
int i;
enum reason_type rv = OTHERS;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &prf);
p += get_opcode(p, &opcode);
CHECK_OP_TYPE(opcode, reg_rop, REG_READ);
CHECK_OP_TYPE(opcode, reg_wop, REG_WRITE);
CHECK_OP_TYPE(opcode, imm_wop, IMM_WRITE);
exit:
return rv;
}
#undef CHECK_OP_TYPE
static unsigned int get_ins_reg_width(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char *p;
struct prefix_bits prf;
int i;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &prf);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(rw8); i++)
if (rw8[i] == opcode)
return 1;
for (i = 0; i < ARRAY_SIZE(rw32); i++)
if (rw32[i] == opcode)
return prf.shorted ? 2 : (prf.enlarged ? 8 : 4);
printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
return 0;
}
unsigned int get_ins_mem_width(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char *p;
struct prefix_bits prf;
int i;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &prf);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(mw8); i++)
if (mw8[i] == opcode)
return 1;
for (i = 0; i < ARRAY_SIZE(mw16); i++)
if (mw16[i] == opcode)
return 2;
for (i = 0; i < ARRAY_SIZE(mw32); i++)
if (mw32[i] == opcode)
return prf.shorted ? 2 : 4;
for (i = 0; i < ARRAY_SIZE(mw64); i++)
if (mw64[i] == opcode)
return prf.shorted ? 2 : (prf.enlarged ? 8 : 4);
printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
return 0;
}
/*
* Define register ident in mod/rm byte.
* Note: these are NOT the same as in ptrace-abi.h.
*/
enum {
arg_AL = 0,
arg_CL = 1,
arg_DL = 2,
arg_BL = 3,
arg_AH = 4,
arg_CH = 5,
arg_DH = 6,
arg_BH = 7,
arg_AX = 0,
arg_CX = 1,
arg_DX = 2,
arg_BX = 3,
arg_SP = 4,
arg_BP = 5,
arg_SI = 6,
arg_DI = 7,
#ifdef __amd64__
arg_R8 = 8,
arg_R9 = 9,
arg_R10 = 10,
arg_R11 = 11,
arg_R12 = 12,
arg_R13 = 13,
arg_R14 = 14,
arg_R15 = 15
#endif
};
static unsigned char *get_reg_w8(int no, int rex, struct pt_regs *regs)
{
unsigned char *rv = NULL;
switch (no) {
case arg_AL:
rv = (unsigned char *)®s->ax;
break;
case arg_BL:
rv = (unsigned char *)®s->bx;
break;
case arg_CL:
rv = (unsigned char *)®s->cx;
break;
case arg_DL:
rv = (unsigned char *)®s->dx;
break;
#ifdef __amd64__
case arg_R8:
rv = (unsigned char *)®s->r8;
break;
case arg_R9:
rv = (unsigned char *)®s->r9;
break;
case arg_R10:
rv = (unsigned char *)®s->r10;
break;
case arg_R11:
rv = (unsigned char *)®s->r11;
break;
case arg_R12:
rv = (unsigned char *)®s->r12;
break;
case arg_R13:
rv = (unsigned char *)®s->r13;
break;
case arg_R14:
rv = (unsigned char *)®s->r14;
break;
case arg_R15:
rv = (unsigned char *)®s->r15;
break;
#endif
default:
break;
}
if (rv)
return rv;
if (rex) {
/*
* If REX prefix exists, access low bytes of SI etc.
* instead of AH etc.
*/
switch (no) {
case arg_SI:
rv = (unsigned char *)®s->si;
break;
case arg_DI:
rv = (unsigned char *)®s->di;
break;
case arg_BP:
rv = (unsigned char *)®s->bp;
break;
case arg_SP:
rv = (unsigned char *)®s->sp;
break;
default:
break;
}
} else {
switch (no) {
case arg_AH:
rv = 1 + (unsigned char *)®s->ax;
break;
case arg_BH:
rv = 1 + (unsigned char *)®s->bx;
break;
case arg_CH:
rv = 1 + (unsigned char *)®s->cx;
break;
case arg_DH:
rv = 1 + (unsigned char *)®s->dx;
break;
default:
break;
}
}
if (!rv)
printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
return rv;
}
static unsigned long *get_reg_w32(int no, struct pt_regs *regs)
{
unsigned long *rv = NULL;
switch (no) {
case arg_AX:
rv = ®s->ax;
break;
case arg_BX:
rv = ®s->bx;
break;
case arg_CX:
rv = ®s->cx;
break;
case arg_DX:
rv = ®s->dx;
break;
case arg_SP:
rv = ®s->sp;
break;
case arg_BP:
rv = ®s->bp;
break;
case arg_SI:
rv = ®s->si;
break;
case arg_DI:
rv = ®s->di;
break;
#ifdef __amd64__
case arg_R8:
rv = ®s->r8;
break;
case arg_R9:
rv = ®s->r9;
break;
case arg_R10:
rv = ®s->r10;
break;
case arg_R11:
rv = ®s->r11;
break;
case arg_R12:
rv = ®s->r12;
break;
case arg_R13:
rv = ®s->r13;
break;
case arg_R14:
rv = ®s->r14;
break;
case arg_R15:
rv = ®s->r15;
break;
#endif
default:
printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
}
return rv;
}
unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs)
{
unsigned int opcode;
int reg;
unsigned char *p;
struct prefix_bits prf;
int i;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &prf);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(reg_rop); i++)
if (reg_rop[i] == opcode)
goto do_work;
for (i = 0; i < ARRAY_SIZE(reg_wop); i++)
if (reg_wop[i] == opcode)
goto do_work;
printk(KERN_ERR "mmiotrace: Not a register instruction, opcode "
"0x%02x\n", opcode);
goto err;
do_work:
/* for STOS, source register is fixed */
if (opcode == 0xAA || opcode == 0xAB) {
reg = arg_AX;
} else {
unsigned char mod_rm = *p;
reg = ((mod_rm >> 3) & 0x7) | (prf.rexr << 3);
}
switch (get_ins_reg_width(ins_addr)) {
case 1:
return *get_reg_w8(reg, prf.rex, regs);
case 2:
return *(unsigned short *)get_reg_w32(reg, regs);
case 4:
return *(unsigned int *)get_reg_w32(reg, regs);
#ifdef __amd64__
case 8:
return *(unsigned long *)get_reg_w32(reg, regs);
#endif
default:
printk(KERN_ERR "mmiotrace: Error width# %d\n", reg);
}
err:
return 0;
}
unsigned long get_ins_imm_val(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char mod_rm;
unsigned char mod;
unsigned char *p;
struct prefix_bits prf;
int i;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &prf);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(imm_wop); i++)
if (imm_wop[i] == opcode)
goto do_work;
printk(KERN_ERR "mmiotrace: Not an immediate instruction, opcode "
"0x%02x\n", opcode);
goto err;
do_work:
mod_rm = *p;
mod = mod_rm >> 6;
p++;
switch (mod) {
case 0:
/* if r/m is 5 we have a 32 disp (IA32 Manual 3, Table 2-2) */
/* AMD64: XXX Check for address size prefix? */
if ((mod_rm & 0x7) == 0x5)
p += 4;
break;
case 1:
p += 1;
break;
case 2:
p += 4;
break;
case 3:
default:
printk(KERN_ERR "mmiotrace: not a memory access instruction "
"at 0x%lx, rm_mod=0x%02x\n",
ins_addr, mod_rm);
}
switch (get_ins_reg_width(ins_addr)) {
case 1:
return *(unsigned char *)p;
case 2:
return *(unsigned short *)p;
case 4:
return *(unsigned int *)p;
#ifdef __amd64__
case 8:
return *(unsigned long *)p;
#endif
default:
printk(KERN_ERR "mmiotrace: Error: width.\n");
}
err:
return 0;
}