arch/mips/kernel/ptrace32.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1992 Ross Biro
   7  * Copyright (C) Linus Torvalds
   8  * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
   9  * Copyright (C) 1996 David S. Miller
  10  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
  11  * Copyright (C) 1999 MIPS Technologies, Inc.
  12  * Copyright (C) 2000 Ulf Carlsson
  13  *
  14  * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
  15  * binaries.
  16  */
  17 #include <linux/compiler.h>
  18 #include <linux/compat.h>
  19 #include <linux/kernel.h>
  20 #include <linux/sched.h>
  21 #include <linux/mm.h>
  22 #include <linux/errno.h>
  23 #include <linux/ptrace.h>
  24 #include <linux/smp.h>
  25 #include <linux/security.h>
  26
  27 #include <asm/cpu.h>
  28 #include <asm/dsp.h>
  29 #include <asm/fpu.h>
  30 #include <asm/mipsregs.h>
  31 #include <asm/mipsmtregs.h>
  32 #include <asm/pgtable.h>
  33 #include <asm/page.h>
  34 #include <asm/reg.h>
  35 #include <asm/uaccess.h>
  36 #include <asm/bootinfo.h>
  37
  38 /*
  39  * Tracing a 32-bit process with a 64-bit strace and vice versa will not
  40  * work.  I don't know how to fix this.
  41  */
  42 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
  43                         compat_ulong_t caddr, compat_ulong_t cdata)
  44 {
  45         int addr = caddr;
  46         int data = cdata;
  47         int ret;
  48
  49         switch (request) {
  50
  51         /*
  52          * Read 4 bytes of the other process' storage
  53          *  data is a pointer specifying where the user wants the
  54          *      4 bytes copied into
  55          *  addr is a pointer in the user's storage that contains an 8 byte
  56          *      address in the other process of the 4 bytes that is to be read
  57          * (this is run in a 32-bit process looking at a 64-bit process)
  58          * when I and D space are separate, these will need to be fixed.
  59          */
  60         case PTRACE_PEEKTEXT_3264:
  61         case PTRACE_PEEKDATA_3264: {
  62                 u32 tmp;
  63                 int copied;
  64                 u32 __user * addrOthers;
  65
  66                 ret = -EIO;
  67
  68                 /* Get the addr in the other process that we want to read */
  69                 if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
  70                         break;
  71
  72                 copied = access_process_vm(child, (u64)addrOthers, &tmp,
  73                                 sizeof(tmp), FOLL_FORCE);
  74                 if (copied != sizeof(tmp))
  75                         break;
  76                 ret = put_user(tmp, (u32 __user *) (unsigned long) data);
  77                 break;
  78         }
  79
  80         /* Read the word at location addr in the USER area. */
  81         case PTRACE_PEEKUSR: {
  82                 struct pt_regs *regs;
  83                 union fpureg *fregs;
  84                 unsigned int tmp;
  85
  86                 regs = task_pt_regs(child);
  87                 ret = 0;  /* Default return value. */
  88
  89                 switch (addr) {
  90                 case 0 ... 31:
  91                         tmp = regs->regs[addr];
  92                         break;
  93                 case FPR_BASE ... FPR_BASE + 31:
  94                         if (!tsk_used_math(child)) {
  95                                 /* FP not yet used */
  96                                 tmp = -1;
  97                                 break;
  98                         }
  99                         fregs = get_fpu_regs(child);
 100                         if (test_thread_flag(TIF_32BIT_FPREGS)) {
 101                                 /*
 102                                  * The odd registers are actually the high
 103                                  * order bits of the values stored in the even
 104                                  * registers - unless we're using r2k_switch.S.
 105                                  */
 106                                 tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
 107                                                 addr & 1);
 108                                 break;
 109                         }
 110                         tmp = get_fpr32(&fregs[addr - FPR_BASE], 0);
 111                         break;
 112                 case PC:
 113                         tmp = regs->cp0_epc;
 114                         break;
 115                 case CAUSE:
 116                         tmp = regs->cp0_cause;
 117                         break;
 118                 case BADVADDR:
 119                         tmp = regs->cp0_badvaddr;
 120                         break;
 121                 case MMHI:
 122                         tmp = regs->hi;
 123                         break;
 124                 case MMLO:
 125                         tmp = regs->lo;
 126                         break;
 127                 case FPC_CSR:
 128                         tmp = child->thread.fpu.fcr31;
 129                         break;
 130                 case FPC_EIR:
 131                         /* implementation / version register */
 132                         tmp = boot_cpu_data.fpu_id;
 133                         break;
 134                 case DSP_BASE ... DSP_BASE + 5: {
 135                         dspreg_t *dregs;
 136
 137                         if (!cpu_has_dsp) {
 138                                 tmp = 0;
 139                                 ret = -EIO;
 140                                 goto out;
 141                         }
 142                         dregs = __get_dsp_regs(child);
 143                         tmp = (unsigned long) (dregs[addr - DSP_BASE]);
 144                         break;
 145                 }
 146                 case DSP_CONTROL:
 147                         if (!cpu_has_dsp) {
 148                                 tmp = 0;
 149                                 ret = -EIO;
 150                                 goto out;
 151                         }
 152                         tmp = child->thread.dsp.dspcontrol;
 153                         break;
 154                 default:
 155                         tmp = 0;
 156                         ret = -EIO;
 157                         goto out;
 158                 }
 159                 ret = put_user(tmp, (unsigned __user *) (unsigned long) data);
 160                 break;
 161         }
 162
 163         /*
 164          * Write 4 bytes into the other process' storage
 165          *  data is the 4 bytes that the user wants written
 166          *  addr is a pointer in the user's storage that contains an
 167          *      8 byte address in the other process where the 4 bytes
 168          *      that is to be written
 169          * (this is run in a 32-bit process looking at a 64-bit process)
 170          * when I and D space are separate, these will need to be fixed.
 171          */
 172         case PTRACE_POKETEXT_3264:
 173         case PTRACE_POKEDATA_3264: {
 174                 u32 __user * addrOthers;
 175
 176                 /* Get the addr in the other process that we want to write into */
 177                 ret = -EIO;
 178                 if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
 179                         break;
 180                 ret = 0;
 181                 if (access_process_vm(child, (u64)addrOthers, &data,
 182                                         sizeof(data),
 183                                         FOLL_FORCE | FOLL_WRITE) == sizeof(data))
 184                         break;
 185                 ret = -EIO;
 186                 break;
 187         }
 188
 189         case PTRACE_POKEUSR: {
 190                 struct pt_regs *regs;
 191                 ret = 0;
 192                 regs = task_pt_regs(child);
 193
 194                 switch (addr) {
 195                 case 0 ... 31:
 196                         regs->regs[addr] = data;
 197                         break;
 198                 case FPR_BASE ... FPR_BASE + 31: {
 199                         union fpureg *fregs = get_fpu_regs(child);
 200
 201                         if (!tsk_used_math(child)) {
 202                                 /* FP not yet used  */
 203                                 memset(&child->thread.fpu, ~0,
 204                                        sizeof(child->thread.fpu));
 205                                 child->thread.fpu.fcr31 = 0;
 206                         }
 207                         if (test_thread_flag(TIF_32BIT_FPREGS)) {
 208                                 /*
 209                                  * The odd registers are actually the high
 210                                  * order bits of the values stored in the even
 211                                  * registers - unless we're using r2k_switch.S.
 212                                  */
 213                                 set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
 214                                           addr & 1, data);
 215                                 break;
 216                         }
 217                         set_fpr64(&fregs[addr - FPR_BASE], 0, data);
 218                         break;
 219                 }
 220                 case PC:
 221                         regs->cp0_epc = data;
 222                         break;
 223                 case MMHI:
 224                         regs->hi = data;
 225                         break;
 226                 case MMLO:
 227                         regs->lo = data;
 228                         break;
 229                 case FPC_CSR:
 230                         child->thread.fpu.fcr31 = data;
 231                         break;
 232                 case DSP_BASE ... DSP_BASE + 5: {
 233                         dspreg_t *dregs;
 234
 235                         if (!cpu_has_dsp) {
 236                                 ret = -EIO;
 237                                 break;
 238                         }
 239
 240                         dregs = __get_dsp_regs(child);
 241                         dregs[addr - DSP_BASE] = data;
 242                         break;
 243                 }
 244                 case DSP_CONTROL:
 245                         if (!cpu_has_dsp) {
 246                                 ret = -EIO;
 247                                 break;
 248                         }
 249                         child->thread.dsp.dspcontrol = data;
 250                         break;
 251                 default:
 252                         /* The rest are not allowed. */
 253                         ret = -EIO;
 254                         break;
 255                 }
 256                 break;
 257                 }
 258
 259         case PTRACE_GETREGS:
 260                 ret = ptrace_getregs(child,
 261                                 (struct user_pt_regs __user *) (__u64) data);
 262                 break;
 263
 264         case PTRACE_SETREGS:
 265                 ret = ptrace_setregs(child,
 266                                 (struct user_pt_regs __user *) (__u64) data);
 267                 break;
 268
 269         case PTRACE_GETFPREGS:
 270                 ret = ptrace_getfpregs(child, (__u32 __user *) (__u64) data);
 271                 break;
 272
 273         case PTRACE_SETFPREGS:
 274                 ret = ptrace_setfpregs(child, (__u32 __user *) (__u64) data);
 275                 break;
 276
 277         case PTRACE_GET_THREAD_AREA:
 278                 ret = put_user(task_thread_info(child)->tp_value,
 279                                 (unsigned int __user *) (unsigned long) data);
 280                 break;
 281
 282         case PTRACE_GET_THREAD_AREA_3264:
 283                 ret = put_user(task_thread_info(child)->tp_value,
 284                                 (unsigned long __user *) (unsigned long) data);
 285                 break;
 286
 287         case PTRACE_GET_WATCH_REGS:
 288                 ret = ptrace_get_watch_regs(child,
 289                         (struct pt_watch_regs __user *) (unsigned long) addr);
 290                 break;
 291
 292         case PTRACE_SET_WATCH_REGS:
 293                 ret = ptrace_set_watch_regs(child,
 294                         (struct pt_watch_regs __user *) (unsigned long) addr);
 295                 break;
 296
 297         default:
 298                 ret = compat_ptrace_request(child, request, addr, data);
 299                 break;
 300         }
 301 out:
 302         return ret;
 303 }