arch/powerpc/kernel/ptrace/ptrace32.c

   1 /*
   2  * ptrace for 32-bit processes running on a 64-bit kernel.
   3  *
   4  *  PowerPC version
   5  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   6  *
   7  *  Derived from "arch/m68k/kernel/ptrace.c"
   8  *  Copyright (C) 1994 by Hamish Macdonald
   9  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
  10  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
  11  *
  12  * Modified by Cort Dougan (cort@hq.fsmlabs.com)
  13  * and Paul Mackerras (paulus@samba.org).
  14  *
  15  * This file is subject to the terms and conditions of the GNU General
  16  * Public License.  See the file COPYING in the main directory of
  17  * this archive for more details.
  18  */
  19
  20 #include <linux/ptrace.h>
  21 #include <linux/regset.h>
  22 #include <linux/compat.h>
  23
  24 #include <asm/switch_to.h>
  25
  26 #include "ptrace-decl.h"
  27
  28 /*
  29  * does not yet catch signals sent when the child dies.
  30  * in exit.c or in signal.c.
  31  */
  32
  33 /* Macros to workout the correct index for the FPR in the thread struct */
  34 #define FPRNUMBER(i) (((i) - PT_FPR0) >> 1)
  35 #define FPRHALF(i) (((i) - PT_FPR0) & 1)
  36 #define FPRINDEX(i) TS_FPRWIDTH * FPRNUMBER(i) * 2 + FPRHALF(i)
  37
  38 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
  39                         compat_ulong_t caddr, compat_ulong_t cdata)
  40 {
  41         unsigned long addr = caddr;
  42         unsigned long data = cdata;
  43         int ret;
  44
  45         switch (request) {
  46         /*
  47          * Read 4 bytes of the other process' storage
  48          *  data is a pointer specifying where the user wants the
  49          *      4 bytes copied into
  50          *  addr is a pointer in the user's storage that contains an 8 byte
  51          *      address in the other process of the 4 bytes that is to be read
  52          * (this is run in a 32-bit process looking at a 64-bit process)
  53          * when I and D space are separate, these will need to be fixed.
  54          */
  55         case PPC_PTRACE_PEEKTEXT_3264:
  56         case PPC_PTRACE_PEEKDATA_3264: {
  57                 u32 tmp;
  58                 int copied;
  59                 u32 __user * addrOthers;
  60
  61                 ret = -EIO;
  62
  63                 /* Get the addr in the other process that we want to read */
  64                 if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
  65                         break;
  66
  67                 copied = ptrace_access_vm(child, (u64)addrOthers, &tmp,
  68                                 sizeof(tmp), FOLL_FORCE);
  69                 if (copied != sizeof(tmp))
  70                         break;
  71                 ret = put_user(tmp, (u32 __user *)data);
  72                 break;
  73         }
  74
  75         /* Read a register (specified by ADDR) out of the "user area" */
  76         case PTRACE_PEEKUSR: {
  77                 int index;
  78                 unsigned long tmp;
  79
  80                 ret = -EIO;
  81                 /* convert to index and check */
  82                 index = (unsigned long) addr >> 2;
  83                 if ((addr & 3) || (index > PT_FPSCR32))
  84                         break;
  85
  86                 CHECK_FULL_REGS(child->thread.regs);
  87                 if (index < PT_FPR0) {
  88                         ret = ptrace_get_reg(child, index, &tmp);
  89                         if (ret)
  90                                 break;
  91                 } else {
  92                         flush_fp_to_thread(child);
  93                         /*
  94                          * the user space code considers the floating point
  95                          * to be an array of unsigned int (32 bits) - the
  96                          * index passed in is based on this assumption.
  97                          */
  98                         tmp = ((unsigned int *)child->thread.fp_state.fpr)
  99                                 [FPRINDEX(index)];
 100                 }
 101                 ret = put_user((unsigned int)tmp, (u32 __user *)data);
 102                 break;
 103         }
 104
 105         /*
 106          * Read 4 bytes out of the other process' pt_regs area
 107          *  data is a pointer specifying where the user wants the
 108          *      4 bytes copied into
 109          *  addr is the offset into the other process' pt_regs structure
 110          *      that is to be read
 111          * (this is run in a 32-bit process looking at a 64-bit process)
 112          */
 113         case PPC_PTRACE_PEEKUSR_3264: {
 114                 u32 index;
 115                 u32 reg32bits;
 116                 u64 tmp;
 117                 u32 numReg;
 118                 u32 part;
 119
 120                 ret = -EIO;
 121                 /* Determine which register the user wants */
 122                 index = (u64)addr >> 2;
 123                 numReg = index / 2;
 124                 /* Determine which part of the register the user wants */
 125                 if (index % 2)
 126                         part = 1;  /* want the 2nd half of the register (right-most). */
 127                 else
 128                         part = 0;  /* want the 1st half of the register (left-most). */
 129
 130                 /* Validate the input - check to see if address is on the wrong boundary
 131                  * or beyond the end of the user area
 132                  */
 133                 if ((addr & 3) || numReg > PT_FPSCR)
 134                         break;
 135
 136                 CHECK_FULL_REGS(child->thread.regs);
 137                 if (numReg >= PT_FPR0) {
 138                         flush_fp_to_thread(child);
 139                         /* get 64 bit FPR */
 140                         tmp = child->thread.fp_state.fpr[numReg - PT_FPR0][0];
 141                 } else { /* register within PT_REGS struct */
 142                         unsigned long tmp2;
 143                         ret = ptrace_get_reg(child, numReg, &tmp2);
 144                         if (ret)
 145                                 break;
 146                         tmp = tmp2;
 147                 }
 148                 reg32bits = ((u32*)&tmp)[part];
 149                 ret = put_user(reg32bits, (u32 __user *)data);
 150                 break;
 151         }
 152
 153         /*
 154          * Write 4 bytes into the other process' storage
 155          *  data is the 4 bytes that the user wants written
 156          *  addr is a pointer in the user's storage that contains an
 157          *      8 byte address in the other process where the 4 bytes
 158          *      that is to be written
 159          * (this is run in a 32-bit process looking at a 64-bit process)
 160          * when I and D space are separate, these will need to be fixed.
 161          */
 162         case PPC_PTRACE_POKETEXT_3264:
 163         case PPC_PTRACE_POKEDATA_3264: {
 164                 u32 tmp = data;
 165                 u32 __user * addrOthers;
 166
 167                 /* Get the addr in the other process that we want to write into */
 168                 ret = -EIO;
 169                 if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
 170                         break;
 171                 ret = 0;
 172                 if (ptrace_access_vm(child, (u64)addrOthers, &tmp,
 173                                         sizeof(tmp),
 174                                         FOLL_FORCE | FOLL_WRITE) == sizeof(tmp))
 175                         break;
 176                 ret = -EIO;
 177                 break;
 178         }
 179
 180         /* write the word at location addr in the USER area */
 181         case PTRACE_POKEUSR: {
 182                 unsigned long index;
 183
 184                 ret = -EIO;
 185                 /* convert to index and check */
 186                 index = (unsigned long) addr >> 2;
 187                 if ((addr & 3) || (index > PT_FPSCR32))
 188                         break;
 189
 190                 CHECK_FULL_REGS(child->thread.regs);
 191                 if (index < PT_FPR0) {
 192                         ret = ptrace_put_reg(child, index, data);
 193                 } else {
 194                         flush_fp_to_thread(child);
 195                         /*
 196                          * the user space code considers the floating point
 197                          * to be an array of unsigned int (32 bits) - the
 198                          * index passed in is based on this assumption.
 199                          */
 200                         ((unsigned int *)child->thread.fp_state.fpr)
 201                                 [FPRINDEX(index)] = data;
 202                         ret = 0;
 203                 }
 204                 break;
 205         }
 206
 207         /*
 208          * Write 4 bytes into the other process' pt_regs area
 209          *  data is the 4 bytes that the user wants written
 210          *  addr is the offset into the other process' pt_regs structure
 211          *      that is to be written into
 212          * (this is run in a 32-bit process looking at a 64-bit process)
 213          */
 214         case PPC_PTRACE_POKEUSR_3264: {
 215                 u32 index;
 216                 u32 numReg;
 217
 218                 ret = -EIO;
 219                 /* Determine which register the user wants */
 220                 index = (u64)addr >> 2;
 221                 numReg = index / 2;
 222
 223                 /*
 224                  * Validate the input - check to see if address is on the
 225                  * wrong boundary or beyond the end of the user area
 226                  */
 227                 if ((addr & 3) || (numReg > PT_FPSCR))
 228                         break;
 229                 CHECK_FULL_REGS(child->thread.regs);
 230                 if (numReg < PT_FPR0) {
 231                         unsigned long freg;
 232                         ret = ptrace_get_reg(child, numReg, &freg);
 233                         if (ret)
 234                                 break;
 235                         if (index % 2)
 236                                 freg = (freg & ~0xfffffffful) | (data & 0xfffffffful);
 237                         else
 238                                 freg = (freg & 0xfffffffful) | (data << 32);
 239                         ret = ptrace_put_reg(child, numReg, freg);
 240                 } else {
 241                         u64 *tmp;
 242                         flush_fp_to_thread(child);
 243                         /* get 64 bit FPR ... */
 244                         tmp = &child->thread.fp_state.fpr[numReg - PT_FPR0][0];
 245                         /* ... write the 32 bit part we want */
 246                         ((u32 *)tmp)[index % 2] = data;
 247                         ret = 0;
 248                 }
 249                 break;
 250         }
 251
 252         case PTRACE_GET_DEBUGREG: {
 253 #ifndef CONFIG_PPC_ADV_DEBUG_REGS
 254                 unsigned long dabr_fake;
 255 #endif
 256                 ret = -EINVAL;
 257                 /* We only support one DABR and no IABRS at the moment */
 258                 if (addr > 0)
 259                         break;
 260 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 261                 ret = put_user(child->thread.debug.dac1, (u32 __user *)data);
 262 #else
 263                 dabr_fake = (
 264                         (child->thread.hw_brk[0].address & (~HW_BRK_TYPE_DABR)) |
 265                         (child->thread.hw_brk[0].type & HW_BRK_TYPE_DABR));
 266                 ret = put_user(dabr_fake, (u32 __user *)data);
 267 #endif
 268                 break;
 269         }
 270
 271         case PTRACE_GETREGS:    /* Get all pt_regs from the child. */
 272                 return copy_regset_to_user(
 273                         child, task_user_regset_view(current), 0,
 274                         0, PT_REGS_COUNT * sizeof(compat_long_t),
 275                         compat_ptr(data));
 276
 277         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 278                 return copy_regset_from_user(
 279                         child, task_user_regset_view(current), 0,
 280                         0, PT_REGS_COUNT * sizeof(compat_long_t),
 281                         compat_ptr(data));
 282
 283         case PTRACE_GETFPREGS:
 284         case PTRACE_SETFPREGS:
 285         case PTRACE_GETVRREGS:
 286         case PTRACE_SETVRREGS:
 287         case PTRACE_GETVSRREGS:
 288         case PTRACE_SETVSRREGS:
 289         case PTRACE_GETREGS64:
 290         case PTRACE_SETREGS64:
 291         case PTRACE_KILL:
 292         case PTRACE_SINGLESTEP:
 293         case PTRACE_DETACH:
 294         case PTRACE_SET_DEBUGREG:
 295         case PTRACE_SYSCALL:
 296         case PTRACE_CONT:
 297         case PPC_PTRACE_GETHWDBGINFO:
 298         case PPC_PTRACE_SETHWDEBUG:
 299         case PPC_PTRACE_DELHWDEBUG:
 300                 ret = arch_ptrace(child, request, addr, data);
 301                 break;
 302
 303         default:
 304                 ret = compat_ptrace_request(child, request, addr, data);
 305                 break;
 306         }
 307
 308         return ret;
 309 }