granicus.if.org Git - strace/blob - prctl.c

   1 /*
   2  * Copyright (c) 1994-1996 Rick Sladkey <jrs@world.std.com>
   3  * Copyright (c) 1996-2000 Wichert Akkerman <wichert@cistron.nl>
   4  * Copyright (c) 2005-2007 Roland McGrath <roland@redhat.com>
   5  * Copyright (c) 2008-2015 Dmitry V. Levin <ldv@altlinux.org>
   6  * Copyright (c) 2014-2017 The strace developers.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. The name of the author may not be used to endorse or promote products
  18  *    derived from this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include "defs.h"
  33
  34 #include <linux/prctl.h>
  35
  36 #include "xlat/prctl_options.h"
  37 #include "xlat/pr_cap_ambient.h"
  38 #include "xlat/pr_dumpable.h"
  39 #include "xlat/pr_fp_mode.h"
  40 #include "xlat/pr_mce_kill.h"
  41 #include "xlat/pr_mce_kill_policy.h"
  42 #include "xlat/pr_set_mm.h"
  43 #include "xlat/pr_tsc.h"
  44 #include "xlat/pr_unalign_flags.h"
  45
  46 #ifndef TASK_COMM_LEN
  47 # define TASK_COMM_LEN 16
  48 #endif
  49
  50 #ifdef HAVE_LINUX_SECCOMP_H
  51 # include <linux/seccomp.h>
  52 #endif
  53 #include "xlat/seccomp_mode.h"
  54
  55 #ifdef HAVE_LINUX_SECUREBITS_H
  56 # include <linux/securebits.h>
  57 #endif
  58 #include "xlat/secbits.h"
  59
  60 /* these constants are the same as in <linux/capability.h> */
  61 enum {
  62 #include "caps0.h"
  63 #include "caps1.h"
  64 };
  65
  66 #include "xlat/cap.h"
  67
  68 static void
  69 print_prctl_args(struct tcb *tcp, const unsigned int first)
  70 {
  71         unsigned int i;
  72
  73         for (i = first; i < tcp->s_ent->nargs; ++i)
  74                 tprintf(", %#" PRI_klx, tcp->u_arg[i]);
  75 }
  76
  77 SYS_FUNC(prctl)
  78 {
  79         const unsigned int option = tcp->u_arg[0];
  80         const kernel_ulong_t arg2 = tcp->u_arg[1];
  81         const kernel_ulong_t arg3 = tcp->u_arg[2];
  82         /*
  83          * PR_SET_VMA is the only command which actually uses these arguments
  84          * currently, and it is available only on Android for now.
  85          */
  86 #ifdef __ANDROID__
  87         const kernel_ulong_t arg4 = tcp->u_arg[3];
  88         const kernel_ulong_t arg5 = tcp->u_arg[4];
  89 #endif
  90         unsigned int i;
  91
  92         if (entering(tcp))
  93                 printxval(prctl_options, option, "PR_???");
  94
  95         switch (option) {
  96         case PR_GET_KEEPCAPS:
  97         case PR_GET_SECCOMP:
  98         case PR_GET_TIMERSLACK:
  99         case PR_GET_TIMING:
 100                 return RVAL_DECODED;
 101
 102         case PR_GET_CHILD_SUBREAPER:
 103         case PR_GET_ENDIAN:
 104         case PR_GET_FPEMU:
 105         case PR_GET_FPEXC:
 106                 if (entering(tcp))
 107                         tprints(", ");
 108                 else
 109                         printnum_int(tcp, arg2, "%u");
 110                 break;
 111
 112         case PR_GET_DUMPABLE:
 113                 if (entering(tcp))
 114                         break;
 115                 if (syserror(tcp))
 116                         return 0;
 117                 tcp->auxstr = xlookup(pr_dumpable, (kernel_ulong_t) tcp->u_rval);
 118                 return RVAL_STR;
 119
 120         case PR_GET_NAME:
 121                 if (entering(tcp)) {
 122                         tprints(", ");
 123                 } else {
 124                         if (syserror(tcp))
 125                                 printaddr(arg2);
 126                         else
 127                                 printstr_ex(tcp, arg2, TASK_COMM_LEN,
 128                                             QUOTE_0_TERMINATED);
 129                 }
 130                 break;
 131
 132         case PR_GET_PDEATHSIG:
 133                 if (entering(tcp)) {
 134                         tprints(", ");
 135                 } else if (!umove_or_printaddr(tcp, arg2, &i)) {
 136                         tprints("[");
 137                         tprints(signame(i));
 138                         tprints("]");
 139                 }
 140                 break;
 141
 142         case PR_GET_SECUREBITS:
 143                 if (entering(tcp))
 144                         break;
 145                 if (syserror(tcp) || tcp->u_rval == 0)
 146                         return 0;
 147                 tcp->auxstr = sprintflags("", secbits,
 148                                           (kernel_ulong_t) tcp->u_rval);
 149                 return RVAL_STR;
 150
 151         case PR_GET_TID_ADDRESS:
 152                 if (entering(tcp))
 153                         tprints(", ");
 154                 else
 155                         printnum_kptr(tcp, arg2);
 156                 break;
 157
 158         case PR_GET_TSC:
 159                 if (entering(tcp)) {
 160                         tprints(", ");
 161                 } else if (!umove_or_printaddr(tcp, arg2, &i)) {
 162                         tprints("[");
 163                         printxval(pr_tsc, i, "PR_TSC_???");
 164                         tprints("]");
 165                 }
 166                 break;
 167
 168         case PR_GET_UNALIGN:
 169                 if (entering(tcp)) {
 170                         tprints(", ");
 171                 } else if (!umove_or_printaddr(tcp, arg2, &i)) {
 172                         tprints("[");
 173                         printflags(pr_unalign_flags, i, "PR_UNALIGN_???");
 174                         tprints("]");
 175                 }
 176                 break;
 177
 178         case PR_GET_FP_MODE:
 179                 if (entering(tcp))
 180                         break;
 181                 if (syserror(tcp) || tcp->u_rval == 0)
 182                         return 0;
 183                 tcp->auxstr = sprintflags("", pr_fp_mode,
 184                                           (kernel_ulong_t) tcp->u_rval);
 185                 return RVAL_STR;
 186
 187         /* PR_TASK_PERF_EVENTS_* take no arguments. */
 188         case PR_TASK_PERF_EVENTS_DISABLE:
 189         case PR_TASK_PERF_EVENTS_ENABLE:
 190                 return RVAL_DECODED;
 191
 192         case PR_SET_CHILD_SUBREAPER:
 193         case PR_SET_ENDIAN:
 194         case PR_SET_FPEMU:
 195         case PR_SET_FPEXC:
 196         case PR_SET_KEEPCAPS:
 197         case PR_SET_TIMING:
 198                 tprintf(", %" PRI_klu, arg2);
 199                 return RVAL_DECODED;
 200
 201         case PR_SET_DUMPABLE:
 202                 tprints(", ");
 203                 printxval64(pr_dumpable, arg2, "SUID_DUMP_???");
 204                 return RVAL_DECODED;
 205
 206         case PR_CAPBSET_DROP:
 207         case PR_CAPBSET_READ:
 208                 tprints(", ");
 209                 printxval64(cap, arg2, "CAP_???");
 210                 return RVAL_DECODED;
 211
 212         case PR_CAP_AMBIENT:
 213                 tprints(", ");
 214                 printxval64(pr_cap_ambient, arg2,
 215                                "PR_CAP_AMBIENT_???");
 216                 switch (arg2) {
 217                 case PR_CAP_AMBIENT_RAISE:
 218                 case PR_CAP_AMBIENT_LOWER:
 219                 case PR_CAP_AMBIENT_IS_SET:
 220                         tprints(", ");
 221                         printxval64(cap, arg3, "CAP_???");
 222                         print_prctl_args(tcp, 3);
 223                         break;
 224                 default:
 225                         print_prctl_args(tcp, 2);
 226                         break;
 227                 }
 228                 return RVAL_DECODED;
 229
 230         case PR_MCE_KILL:
 231                 tprints(", ");
 232                 printxval64(pr_mce_kill, arg2, "PR_MCE_KILL_???");
 233                 tprints(", ");
 234                 if (PR_MCE_KILL_SET == arg2)
 235                         printxval64(pr_mce_kill_policy, arg3,
 236                                     "PR_MCE_KILL_???");
 237                 else
 238                         tprintf("%#" PRI_klx, arg3);
 239                 print_prctl_args(tcp, 3);
 240                 return RVAL_DECODED;
 241
 242         case PR_SET_NAME:
 243                 tprints(", ");
 244                 printstr_ex(tcp, arg2, TASK_COMM_LEN - 1,
 245                             QUOTE_0_TERMINATED);
 246                 return RVAL_DECODED;
 247
 248 #ifdef __ANDROID__
 249 # ifndef PR_SET_VMA_ANON_NAME
 250 #  define PR_SET_VMA_ANON_NAME    0
 251 # endif
 252         case PR_SET_VMA:
 253                 if (arg2 == PR_SET_VMA_ANON_NAME) {
 254                         tprintf(", PR_SET_VMA_ANON_NAME, %#" PRI_klx, arg3);
 255                         tprintf(", %" PRI_klu ", ", arg4);
 256                         printstr(tcp, arg5);
 257                 } else {
 258                         /* There are no other sub-options now, but there
 259                          * might be in future... */
 260                         print_prctl_args(tcp, 1);
 261                 }
 262                 return RVAL_DECODED;
 263 #endif
 264
 265         case PR_SET_MM:
 266                 tprints(", ");
 267                 printxval(pr_set_mm, arg2, "PR_SET_MM_???");
 268                 print_prctl_args(tcp, 2);
 269                 return RVAL_DECODED;
 270
 271         case PR_SET_PDEATHSIG:
 272                 tprints(", ");
 273                 if (arg2 > 128)
 274                         tprintf("%" PRI_klu, arg2);
 275                 else
 276                         tprints(signame(arg2));
 277                 return RVAL_DECODED;
 278
 279         case PR_SET_PTRACER:
 280                 tprints(", ");
 281                 if ((int) arg2 == -1)
 282                         tprints("PR_SET_PTRACER_ANY");
 283                 else
 284                         tprintf("%" PRI_klu, arg2);
 285                 return RVAL_DECODED;
 286
 287         case PR_SET_SECCOMP:
 288                 tprints(", ");
 289                 printxval64(seccomp_mode, arg2,
 290                             "SECCOMP_MODE_???");
 291                 if (SECCOMP_MODE_STRICT == arg2)
 292                         return RVAL_DECODED;
 293                 if (SECCOMP_MODE_FILTER == arg2) {
 294                         tprints(", ");
 295                         print_seccomp_filter(tcp, arg3);
 296                         return RVAL_DECODED;
 297                 }
 298                 print_prctl_args(tcp, 2);
 299                 return RVAL_DECODED;
 300
 301         case PR_SET_SECUREBITS:
 302                 tprints(", ");
 303                 printflags64(secbits, arg2, "SECBIT_???");
 304                 return RVAL_DECODED;
 305
 306         case PR_SET_TIMERSLACK:
 307                 tprintf(", %" PRI_kld, arg2);
 308                 return RVAL_DECODED;
 309
 310         case PR_SET_TSC:
 311                 tprints(", ");
 312                 printxval(pr_tsc, arg2, "PR_TSC_???");
 313                 return RVAL_DECODED;
 314
 315         case PR_SET_UNALIGN:
 316                 tprints(", ");
 317                 printflags(pr_unalign_flags, arg2, "PR_UNALIGN_???");
 318                 return RVAL_DECODED;
 319
 320         case PR_SET_NO_NEW_PRIVS:
 321         case PR_SET_THP_DISABLE:
 322                 tprintf(", %" PRI_klu, arg2);
 323                 print_prctl_args(tcp, 2);
 324                 return RVAL_DECODED;
 325
 326         case PR_MCE_KILL_GET:
 327                 if (entering(tcp)) {
 328                         print_prctl_args(tcp, 1);
 329                         return 0;
 330                 }
 331                 if (syserror(tcp))
 332                         return 0;
 333                 tcp->auxstr = xlookup(pr_mce_kill_policy,
 334                                       (kernel_ulong_t) tcp->u_rval);
 335                 return tcp->auxstr ? RVAL_STR : RVAL_UDECIMAL;
 336
 337         case PR_SET_FP_MODE:
 338                 tprints(", ");
 339                 printflags(pr_fp_mode, arg2, "PR_FP_MODE_???");
 340                 return RVAL_DECODED;
 341
 342         case PR_GET_NO_NEW_PRIVS:
 343         case PR_GET_THP_DISABLE:
 344         case PR_MPX_DISABLE_MANAGEMENT:
 345         case PR_MPX_ENABLE_MANAGEMENT:
 346         default:
 347                 print_prctl_args(tcp, 1);
 348                 return RVAL_DECODED;
 349         }
 350         return 0;
 351 }
 352
 353 #if defined X86_64 || defined X32
 354 # include <asm/prctl.h>
 355 # include "xlat/archvals.h"
 356
 357 SYS_FUNC(arch_prctl)
 358 {
 359         const unsigned int option = tcp->u_arg[0];
 360         const kernel_ulong_t addr = tcp->u_arg[1];
 361
 362         if (entering(tcp))
 363                 printxval(archvals, option, "ARCH_???");
 364
 365         switch (option) {
 366         case ARCH_GET_GS:
 367         case ARCH_GET_FS:
 368                 if (entering(tcp))
 369                         tprints(", ");
 370                 else
 371                         printnum_ptr(tcp, addr);
 372                 return 0;
 373         }
 374
 375         tprintf(", %#" PRI_klx, addr);
 376         return RVAL_DECODED;
 377 }
 378 #endif /* X86_64 || X32 */