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

   1 /*
   2  * Check decoding of prctl PR_GET_TID_ADDRESS operation.
   3  *
   4  * Copyright (c) 2016 Eugene Syromyatnikov <evgsyr@gmail.com>
   5  * Copyright (c) 2016-2018 The strace developers.
   6  * All rights reserved.
   7  *
   8  * SPDX-License-Identifier: GPL-2.0-or-later
   9  */
  10
  11 #include "tests.h"
  12 #include <asm/unistd.h>
  13 #include <linux/prctl.h>
  14
  15 #if defined __NR_prctl && defined __NR_set_tid_address && \
  16         defined PR_GET_TID_ADDRESS
  17
  18 # include <inttypes.h>
  19 # include <stdio.h>
  20 # include <unistd.h>
  21
  22 static const char *
  23 sprintaddr(kernel_ulong_t addr)
  24 {
  25         static char buf[sizeof("0x") + sizeof(addr) * 2];
  26
  27         if (addr) {
  28                 snprintf(buf, sizeof(buf), "%#llx", (unsigned long long) addr);
  29
  30                 return buf;
  31         }
  32
  33         return "NULL";
  34 }
  35
  36 int
  37 main(void)
  38 {
  39         static const kernel_ulong_t bogus_addr =
  40                 (kernel_ulong_t) 0xfffffffffffffffdULL;
  41
  42         /* Note that kernel puts kernel-sized pointer even on x32 */
  43         TAIL_ALLOC_OBJECT_CONST_PTR(kernel_ulong_t, ptr);
  44         long rc;
  45         long set_ok;
  46
  47         *ptr = (kernel_ulong_t) 0xbadc0dedda7a1057ULL;
  48
  49         rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, NULL);
  50         printf("prctl(PR_GET_TID_ADDRESS, NULL) = %s\n", sprintrc(rc));
  51
  52         rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, bogus_addr);
  53         printf("prctl(PR_GET_TID_ADDRESS, %#llx) = %s\n",
  54                (unsigned long long) bogus_addr, sprintrc(rc));
  55
  56         rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, ptr);
  57         if (rc) {
  58                 printf("prctl(PR_GET_TID_ADDRESS, %p) = %s\n",
  59                        ptr, sprintrc(rc));
  60         } else {
  61                 printf("prctl(PR_GET_TID_ADDRESS, [%s]) = %s\n",
  62                        sprintaddr(*ptr), sprintrc(rc));
  63         }
  64
  65         set_ok = syscall(__NR_set_tid_address, bogus_addr);
  66
  67         rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, ptr);
  68         if (rc) {
  69                 printf("prctl(PR_GET_TID_ADDRESS, %p) = %s\n",
  70                        ptr, sprintrc(rc));
  71         } else {
  72                 printf("prctl(PR_GET_TID_ADDRESS, [%s]) = %s\n",
  73                        sprintaddr(set_ok ? bogus_addr : *ptr), sprintrc(rc));
  74         }
  75
  76         puts("+++ exited with 0 +++");
  77         return 0;
  78 }
  79
  80 #else
  81
  82 SKIP_MAIN_UNDEFINED("__NR_prctl && __NR_set_tid_address && PR_GET_TID_ADDRESS")
  83
  84 #endif