arch/powerpc/kernel/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/kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/mm.h>
  23 #include <linux/smp.h>
  24 #include <linux/errno.h>
  25 #include <linux/ptrace.h>
  26 #include <linux/regset.h>
  27 #include <linux/user.h>
  28 #include <linux/security.h>
  29 #include <linux/signal.h>
  30 #include <linux/compat.h>
  31
  32 #include <asm/uaccess.h>
  33 #include <asm/page.h>
  34 #include <asm/pgtable.h>
  35 #include <asm/switch_to.h>
  36
  37 /*
  38  * does not yet catch signals sent when the child dies.
  39  * in exit.c or in signal.c.
  40  */
  41
  42 /* Macros to workout the correct index for the FPR in the thread struct */
  43 #define FPRNUMBER(i) (((i) - PT_FPR0) >> 1)
  44 #define FPRHALF(i) (((i) - PT_FPR0) & 1)
  45 #define FPRINDEX(i) TS_FPRWIDTH * FPRNUMBER(i) * 2 + FPRHALF(i)
  46 #define FPRINDEX_3264(i) (TS_FPRWIDTH * ((i) - PT_FPR0))
  47
  48 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
  49                         compat_ulong_t caddr, compat_ulong_t cdata)
  50 {
  51         unsigned long addr = caddr;
  52         unsigned long data = cdata;
  53         int ret;
  54
  55         switch (request) {
  56         /*
  57          * Read 4 bytes of the other process' storage
  58          *  data is a pointer specifying where the user wants the
  59          *      4 bytes copied into
  60          *  addr is a pointer in the user's storage that contains an 8 byte
  61          *      address in the other process of the 4 bytes that is to be read
  62          * (this is run in a 32-bit process looking at a 64-bit process)
  63          * when I and D space are separate, these will need to be fixed.
  64          */
  65         case PPC_PTRACE_PEEKTEXT_3264:
  66         case PPC_PTRACE_PEEKDATA_3264: {
  67                 u32 tmp;
  68                 int copied;
  69                 u32 __user * addrOthers;
  70
  71                 ret = -EIO;
  72
  73                 /* Get the addr in the other process that we want to read */
  74                 if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
  75                         break;
  76
  77                 copied = access_process_vm(child, (u64)addrOthers, &tmp,
  78                                 sizeof(tmp), 0);
  79                 if (copied != sizeof(tmp))
  80                         break;
  81                 ret = put_user(tmp, (u32 __user *)data);
  82                 break;
  83         }
  84
  85         /* Read a register (specified by ADDR) out of the "user area" */
  86         case PTRACE_PEEKUSR: {
  87                 int index;
  88                 unsigned long tmp;
  89
  90                 ret = -EIO;
  91                 /* convert to index and check */
  92                 index = (unsigned long) addr >> 2;
  93                 if ((addr & 3) || (index > PT_FPSCR32))
  94                         break;
  95
  96                 CHECK_FULL_REGS(child->thread.regs);
  97                 if (index < PT_FPR0) {
  98                         ret = ptrace_get_reg(child, index, &tmp);
  99                         if (ret)
 100                                 break;
 101                 } else {
 102                         flush_fp_to_thread(child);
 103                         /*
 104                          * the user space code considers the floating point
 105                          * to be an array of unsigned int (32 bits) - the
 106                          * index passed in is based on this assumption.
 107                          */
 108                         tmp = ((unsigned int *)child->thread.fpr)
 109                                 [FPRINDEX(index)];
 110                 }
 111                 ret = put_user((unsigned int)tmp, (u32 __user *)data);
 112                 break;
 113         }
 114
 115         /*
 116          * Read 4 bytes out of the other process' pt_regs area
 117          *  data is a pointer specifying where the user wants the
 118          *      4 bytes copied into
 119          *  addr is the offset into the other process' pt_regs structure
 120          *      that is to be read
 121          * (this is run in a 32-bit process looking at a 64-bit process)
 122          */
 123         case PPC_PTRACE_PEEKUSR_3264: {
 124                 u32 index;
 125                 u32 reg32bits;
 126                 u64 tmp;
 127                 u32 numReg;
 128                 u32 part;
 129
 130                 ret = -EIO;
 131                 /* Determine which register the user wants */
 132                 index = (u64)addr >> 2;
 133                 numReg = index / 2;
 134                 /* Determine which part of the register the user wants */
 135                 if (index % 2)
 136                         part = 1;  /* want the 2nd half of the register (right-most). */
 137                 else
 138                         part = 0;  /* want the 1st half of the register (left-most). */
 139
 140                 /* Validate the input - check to see if address is on the wrong boundary
 141                  * or beyond the end of the user area
 142                  */
 143                 if ((addr & 3) || numReg > PT_FPSCR)
 144                         break;
 145
 146                 CHECK_FULL_REGS(child->thread.regs);
 147                 if (numReg >= PT_FPR0) {
 148                         flush_fp_to_thread(child);
 149                         /* get 64 bit FPR */
 150                         tmp = ((u64 *)child->thread.fpr)
 151                                 [FPRINDEX_3264(numReg)];
 152                 } else { /* register within PT_REGS struct */
 153                         unsigned long tmp2;
 154                         ret = ptrace_get_reg(child, numReg, &tmp2);
 155                         if (ret)
 156                                 break;
 157                         tmp = tmp2;
 158                 }
 159                 reg32bits = ((u32*)&tmp)[part];
 160                 ret = put_user(reg32bits, (u32 __user *)data);
 161                 break;
 162         }
 163
 164         /*
 165          * Write 4 bytes into the other process' storage
 166          *  data is the 4 bytes that the user wants written
 167          *  addr is a pointer in the user's storage that contains an
 168          *      8 byte address in the other process where the 4 bytes
 169          *      that is to be written
 170          * (this is run in a 32-bit process looking at a 64-bit process)
 171          * when I and D space are separate, these will need to be fixed.
 172          */
 173         case PPC_PTRACE_POKETEXT_3264:
 174         case PPC_PTRACE_POKEDATA_3264: {
 175                 u32 tmp = data;
 176                 u32 __user * addrOthers;
 177
 178                 /* Get the addr in the other process that we want to write into */
 179                 ret = -EIO;
 180                 if (get_user(addrOthers, (u32 __user * __user *)addr) != 0)
 181                         break;
 182                 ret = 0;
 183                 if (access_process_vm(child, (u64)addrOthers, &tmp,
 184                                         sizeof(tmp), 1) == sizeof(tmp))
 185                         break;
 186                 ret = -EIO;
 187                 break;
 188         }
 189
 190         /* write the word at location addr in the USER area */
 191         case PTRACE_POKEUSR: {
 192                 unsigned long index;
 193
 194                 ret = -EIO;
 195                 /* convert to index and check */
 196                 index = (unsigned long) addr >> 2;
 197                 if ((addr & 3) || (index > PT_FPSCR32))
 198                         break;
 199
 200                 CHECK_FULL_REGS(child->thread.regs);
 201                 if (index < PT_FPR0) {
 202                         ret = ptrace_put_reg(child, index, data);
 203                 } else {
 204                         flush_fp_to_thread(child);
 205                         /*
 206                          * the user space code considers the floating point
 207                          * to be an array of unsigned int (32 bits) - the
 208                          * index passed in is based on this assumption.
 209                          */
 210                         ((unsigned int *)child->thread.fpr)
 211                                 [FPRINDEX(index)] = data;
 212                         ret = 0;
 213                 }
 214                 break;
 215         }
 216
 217         /*
 218          * Write 4 bytes into the other process' pt_regs area
 219          *  data is the 4 bytes that the user wants written
 220          *  addr is the offset into the other process' pt_regs structure
 221          *      that is to be written into
 222          * (this is run in a 32-bit process looking at a 64-bit process)
 223          */
 224         case PPC_PTRACE_POKEUSR_3264: {
 225                 u32 index;
 226                 u32 numReg;
 227
 228                 ret = -EIO;
 229                 /* Determine which register the user wants */
 230                 index = (u64)addr >> 2;
 231                 numReg = index / 2;
 232
 233                 /*
 234                  * Validate the input - check to see if address is on the
 235                  * wrong boundary or beyond the end of the user area
 236                  */
 237                 if ((addr & 3) || (numReg > PT_FPSCR))
 238                         break;
 239                 CHECK_FULL_REGS(child->thread.regs);
 240                 if (numReg < PT_FPR0) {
 241                         unsigned long freg;
 242                         ret = ptrace_get_reg(child, numReg, &freg);
 243                         if (ret)
 244                                 break;
 245                         if (index % 2)
 246                                 freg = (freg & ~0xfffffffful) | (data & 0xfffffffful);
 247                         else
 248                                 freg = (freg & 0xfffffffful) | (data << 32);
 249                         ret = ptrace_put_reg(child, numReg, freg);
 250                 } else {
 251                         u64 *tmp;
 252                         flush_fp_to_thread(child);
 253                         /* get 64 bit FPR ... */
 254                         tmp = &(((u64 *)child->thread.fpr)
 255                                 [FPRINDEX_3264(numReg)]);
 256                         /* ... write the 32 bit part we want */
 257                         ((u32 *)tmp)[index % 2] = data;
 258                         ret = 0;
 259                 }
 260                 break;
 261         }
 262
 263         case PTRACE_GET_DEBUGREG: {
 264 #ifndef CONFIG_PPC_ADV_DEBUG_REGS
 265                 unsigned long dabr_fake;
 266 #endif
 267                 ret = -EINVAL;
 268                 /* We only support one DABR and no IABRS at the moment */
 269                 if (addr > 0)
 270                         break;
 271 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 272                 ret = put_user(child->thread.dac1, (u32 __user *)data);
 273 #else
 274                 dabr_fake = (
 275                         (child->thread.hw_brk.address & (~HW_BRK_TYPE_DABR)) |
 276                         (child->thread.hw_brk.type & HW_BRK_TYPE_DABR));
 277                 ret = put_user(dabr_fake, (u32 __user *)data);
 278 #endif
 279                 break;
 280         }
 281
 282         case PTRACE_GETREGS:    /* Get all pt_regs from the child. */
 283                 return copy_regset_to_user(
 284                         child, task_user_regset_view(current), 0,
 285                         0, PT_REGS_COUNT * sizeof(compat_long_t),
 286                         compat_ptr(data));
 287
 288         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 289                 return copy_regset_from_user(
 290                         child, task_user_regset_view(current), 0,
 291                         0, PT_REGS_COUNT * sizeof(compat_long_t),
 292                         compat_ptr(data));
 293
 294         case PTRACE_GETFPREGS:
 295         case PTRACE_SETFPREGS:
 296         case PTRACE_GETVRREGS:
 297         case PTRACE_SETVRREGS:
 298         case PTRACE_GETVSRREGS:
 299         case PTRACE_SETVSRREGS:
 300         case PTRACE_GETREGS64:
 301         case PTRACE_SETREGS64:
 302         case PTRACE_KILL:
 303         case PTRACE_SINGLESTEP:
 304         case PTRACE_DETACH:
 305         case PTRACE_SET_DEBUGREG:
 306         case PTRACE_SYSCALL:
 307         case PTRACE_CONT:
 308         case PPC_PTRACE_GETHWDBGINFO:
 309         case PPC_PTRACE_SETHWDEBUG:
 310         case PPC_PTRACE_DELHWDEBUG:
 311                 ret = arch_ptrace(child, request, addr, data);
 312                 break;
 313
 314         default:
 315                 ret = compat_ptrace_request(child, request, addr, data);
 316                 break;
 317         }
 318
 319         return ret;
 320 }