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