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_fp_mode.h"
  38 #include "xlat/pr_mce_kill.h"
  39 #include "xlat/pr_mce_kill_policy.h"
  40 #include "xlat/pr_set_mm.h"
  41 #include "xlat/pr_tsc.h"
  42 #include "xlat/pr_unalign_flags.h"
  43
  44 #ifndef TASK_COMM_LEN
  45 # define TASK_COMM_LEN 16
  46 #endif
  47
  48 #ifdef HAVE_LINUX_SECCOMP_H
  49 # include <linux/seccomp.h>
  50 #endif
  51 #include "xlat/seccomp_mode.h"
  52
  53 #ifdef HAVE_LINUX_SECUREBITS_H
  54 # include <linux/securebits.h>
  55 #endif
  56 #include "xlat/secbits.h"
  57
  58 /* these constants are the same as in <linux/capability.h> */
  59 enum {
  60 #include "caps0.h"
  61 #include "caps1.h"
  62 };
  63
  64 #include "xlat/cap.h"
  65
  66 static void
  67 print_prctl_args(struct tcb *tcp, const unsigned int first)
  68 {
  69         unsigned int i;
  70
  71         for (i = first; i < tcp->s_ent->nargs; ++i)
  72                 tprintf(", %#llx", getarg_ull(tcp, i));
  73 }
  74
  75 SYS_FUNC(prctl)
  76 {
  77         const unsigned int option = tcp->u_arg[0];
  78         const unsigned long long arg2 = getarg_ull(tcp, 1);
  79         const unsigned long long arg3 = getarg_ull(tcp, 2);
  80         /*
  81          * PR_SET_VMA is the only command which actually uses these arguments
  82          * currently, and it is available only on Android for now.
  83          */
  84 #ifdef __ANDROID__
  85         const unsigned long long arg4 = getarg_ull(tcp, 3);
  86         const unsigned long long arg5 = getarg_ull(tcp, 4);
  87 #endif
  88         unsigned int i;
  89
  90         if (entering(tcp))
  91                 printxval(prctl_options, option, "PR_???");
  92
  93         switch (option) {
  94         case PR_GET_DUMPABLE:
  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_NAME:
 112                 if (entering(tcp)) {
 113                         tprints(", ");
 114                 } else {
 115                         if (syserror(tcp))
 116                                 printaddr(arg2);
 117                         else
 118                                 printstr_ex(tcp, arg2, TASK_COMM_LEN,
 119                                             QUOTE_0_TERMINATED);
 120                 }
 121                 break;
 122
 123         case PR_GET_PDEATHSIG:
 124                 if (entering(tcp)) {
 125                         tprints(", ");
 126                 } else if (!umove_or_printaddr(tcp, arg2, &i)) {
 127                         tprints("[");
 128                         tprints(signame(i));
 129                         tprints("]");
 130                 }
 131                 break;
 132
 133         case PR_GET_SECUREBITS:
 134                 if (entering(tcp))
 135                         break;
 136                 if (syserror(tcp) || tcp->u_rval == 0)
 137                         return 0;
 138                 tcp->auxstr = sprintflags("", secbits,
 139                                           (unsigned long) tcp->u_rval);
 140                 return RVAL_STR;
 141
 142         case PR_GET_TID_ADDRESS:
 143                 if (entering(tcp))
 144                         tprints(", ");
 145                 else
 146                         printnum_ptr(tcp, arg2);
 147                 break;
 148
 149         case PR_GET_TSC:
 150                 if (entering(tcp)) {
 151                         tprints(", ");
 152                 } else if (!umove_or_printaddr(tcp, arg2, &i)) {
 153                         tprints("[");
 154                         printxval(pr_tsc, i, "PR_TSC_???");
 155                         tprints("]");
 156                 }
 157                 break;
 158
 159         case PR_GET_UNALIGN:
 160                 if (entering(tcp)) {
 161                         tprints(", ");
 162                 } else if (!umove_or_printaddr(tcp, arg2, &i)) {
 163                         tprints("[");
 164                         printflags(pr_unalign_flags, i, "PR_UNALIGN_???");
 165                         tprints("]");
 166                 }
 167                 break;
 168
 169         case PR_GET_FP_MODE:
 170                 if (entering(tcp))
 171                         break;
 172                 if (syserror(tcp) || tcp->u_rval == 0)
 173                         return 0;
 174                 tcp->auxstr = sprintflags("", pr_fp_mode,
 175                                           (unsigned long) tcp->u_rval);
 176                 return RVAL_STR;
 177
 178         /* PR_TASK_PERF_EVENTS_* take no arguments. */
 179         case PR_TASK_PERF_EVENTS_DISABLE:
 180         case PR_TASK_PERF_EVENTS_ENABLE:
 181                 return RVAL_DECODED;
 182
 183         case PR_SET_CHILD_SUBREAPER:
 184         case PR_SET_DUMPABLE:
 185         case PR_SET_ENDIAN:
 186         case PR_SET_FPEMU:
 187         case PR_SET_FPEXC:
 188         case PR_SET_KEEPCAPS:
 189         case PR_SET_TIMING:
 190                 tprintf(", %llu", arg2);
 191                 return RVAL_DECODED;
 192
 193         case PR_CAPBSET_DROP:
 194         case PR_CAPBSET_READ:
 195                 tprints(", ");
 196                 printxval64(cap, arg2, "CAP_???");
 197                 return RVAL_DECODED;
 198
 199         case PR_CAP_AMBIENT:
 200                 tprints(", ");
 201                 printxval64(pr_cap_ambient, arg2,
 202                                "PR_CAP_AMBIENT_???");
 203                 switch (arg2) {
 204                 case PR_CAP_AMBIENT_RAISE:
 205                 case PR_CAP_AMBIENT_LOWER:
 206                 case PR_CAP_AMBIENT_IS_SET:
 207                         tprints(", ");
 208                         printxval64(cap, arg3, "CAP_???");
 209                         print_prctl_args(tcp, 3);
 210                         break;
 211                 default:
 212                         print_prctl_args(tcp, 2);
 213                         break;
 214                 }
 215                 return RVAL_DECODED;
 216
 217         case PR_MCE_KILL:
 218                 tprints(", ");
 219                 printxval64(pr_mce_kill, arg2, "PR_MCE_KILL_???");
 220                 tprints(", ");
 221                 if (PR_MCE_KILL_SET == arg2)
 222                         printxval64(pr_mce_kill_policy, arg3,
 223                                     "PR_MCE_KILL_???");
 224                 else
 225                         tprintf("%#llx", arg3);
 226                 print_prctl_args(tcp, 3);
 227                 return RVAL_DECODED;
 228
 229         case PR_SET_NAME:
 230                 tprints(", ");
 231                 printstr_ex(tcp, arg2, TASK_COMM_LEN - 1,
 232                             QUOTE_0_TERMINATED);
 233                 return RVAL_DECODED;
 234
 235 #ifdef __ANDROID__
 236 # ifndef PR_SET_VMA_ANON_NAME
 237 #  define PR_SET_VMA_ANON_NAME    0
 238 # endif
 239         case PR_SET_VMA:
 240                 if (arg2 == PR_SET_VMA_ANON_NAME) {
 241                         tprintf(", PR_SET_VMA_ANON_NAME, %#llx", arg3);
 242                         tprintf(", %llu, ", arg4);
 243                         printstr(tcp, arg5, -1);
 244                 } else {
 245                         /* There are no other sub-options now, but there
 246                          * might be in future... */
 247                         print_prctl_args(tcp, 1);
 248                 }
 249                 return RVAL_DECODED;
 250 #endif
 251
 252         case PR_SET_MM:
 253                 tprints(", ");
 254                 printxval(pr_set_mm, arg2, "PR_SET_MM_???");
 255                 print_prctl_args(tcp, 2);
 256                 return RVAL_DECODED;
 257
 258         case PR_SET_PDEATHSIG:
 259                 tprints(", ");
 260                 if (arg2 > 128)
 261                         tprintf("%llu", arg2);
 262                 else
 263                         tprints(signame(arg2));
 264                 return RVAL_DECODED;
 265
 266         case PR_SET_PTRACER:
 267                 tprints(", ");
 268                 if ((int) arg2 == -1)
 269                         tprints("PR_SET_PTRACER_ANY");
 270                 else
 271                         tprintf("%llu", arg2);
 272                 return RVAL_DECODED;
 273
 274         case PR_SET_SECCOMP:
 275                 tprints(", ");
 276                 printxval64(seccomp_mode, arg2,
 277                             "SECCOMP_MODE_???");
 278                 if (SECCOMP_MODE_STRICT == arg2)
 279                         return RVAL_DECODED;
 280                 if (SECCOMP_MODE_FILTER == arg2) {
 281                         tprints(", ");
 282                         print_seccomp_filter(tcp, arg3);
 283                         return RVAL_DECODED;
 284                 }
 285                 print_prctl_args(tcp, 2);
 286                 return RVAL_DECODED;
 287
 288         case PR_SET_SECUREBITS:
 289                 tprints(", ");
 290                 printflags64(secbits, arg2, "SECBIT_???");
 291                 return RVAL_DECODED;
 292
 293         case PR_SET_TIMERSLACK:
 294                 tprintf(", %lld", arg2);
 295                 return RVAL_DECODED;
 296
 297         case PR_SET_TSC:
 298                 tprints(", ");
 299                 printxval(pr_tsc, arg2, "PR_TSC_???");
 300                 return RVAL_DECODED;
 301
 302         case PR_SET_UNALIGN:
 303                 tprints(", ");
 304                 printflags(pr_unalign_flags, arg2, "PR_UNALIGN_???");
 305                 return RVAL_DECODED;
 306
 307         case PR_SET_NO_NEW_PRIVS:
 308         case PR_SET_THP_DISABLE:
 309                 tprintf(", %llu", arg2);
 310                 print_prctl_args(tcp, 2);
 311                 return RVAL_DECODED;
 312
 313         case PR_MCE_KILL_GET:
 314                 if (entering(tcp)) {
 315                         print_prctl_args(tcp, 1);
 316                         return 0;
 317                 }
 318                 if (syserror(tcp))
 319                         return 0;
 320                 tcp->auxstr = xlookup(pr_mce_kill_policy,
 321                                       (unsigned long) tcp->u_rval);
 322                 return tcp->auxstr ? RVAL_STR : RVAL_UDECIMAL;
 323
 324         case PR_SET_FP_MODE:
 325                 tprints(", ");
 326                 printflags(pr_fp_mode, arg2, "PR_FP_MODE_???");
 327                 return RVAL_DECODED;
 328
 329         case PR_GET_NO_NEW_PRIVS:
 330         case PR_GET_THP_DISABLE:
 331         case PR_MPX_DISABLE_MANAGEMENT:
 332         case PR_MPX_ENABLE_MANAGEMENT:
 333         default:
 334                 print_prctl_args(tcp, 1);
 335                 return RVAL_DECODED;
 336         }
 337         return 0;
 338 }
 339
 340 #if defined X86_64 || defined X32
 341 # include <asm/prctl.h>
 342 # include "xlat/archvals.h"
 343
 344 SYS_FUNC(arch_prctl)
 345 {
 346         const unsigned int option = tcp->u_arg[0];
 347         const unsigned long long addr = getarg_ull(tcp, 1);
 348
 349         if (entering(tcp))
 350                 printxval(archvals, option, "ARCH_???");
 351
 352         switch (option) {
 353         case ARCH_GET_GS:
 354         case ARCH_GET_FS:
 355                 if (entering(tcp))
 356                         tprints(", ");
 357                 else
 358                         printnum_ptr(tcp, addr);
 359                 return 0;
 360         }
 361
 362         tprintf(", %#llx", addr);
 363         return RVAL_DECODED;
 364 }
 365 #endif /* X86_64 || X32 */