elf/tst-audit23.c

   1 /* Check for expected la_objopen and la_objeclose for all objects.
   2    Copyright (C) 2022-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <array_length.h>
  20 #include <errno.h>
  21 #include <getopt.h>
  22 #include <link.h>
  23 #include <limits.h>
  24 #include <inttypes.h>
  25 #include <gnu/lib-names.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <support/capture_subprocess.h>
  29 #include <support/check.h>
  30 #include <support/xstdio.h>
  31 #include <support/xdlfcn.h>
  32 #include <support/support.h>
  33
  34 static int restart;
  35 #define CMDLINE_OPTIONS \
  36   { "restart", no_argument, &restart, 1 },
  37
  38 static int
  39 handle_restart (void)
  40 {
  41   xdlopen ("tst-audit23mod.so", RTLD_NOW);
  42   xdlmopen (LM_ID_NEWLM, LIBC_SO, RTLD_NOW);
  43
  44   return 0;
  45 }
  46
  47 static inline bool
  48 startswith (const char *str, const char *pre)
  49 {
  50   size_t lenpre = strlen (pre);
  51   size_t lenstr = strlen (str);
  52   return lenstr >= lenpre && memcmp (pre, str, lenpre) == 0;
  53 }
  54
  55 static inline bool
  56 is_vdso (const char *str)
  57 {
  58   return startswith (str, "linux-gate")
  59          || startswith (str, "linux-vdso");
  60 }
  61
  62 static int
  63 do_test (int argc, char *argv[])
  64 {
  65   /* We must have either:
  66      - One or four parameters left if called initially:
  67        + path to ld.so         optional
  68        + "--library-path"      optional
  69        + the library path      optional
  70        + the application name  */
  71   if (restart)
  72     return handle_restart ();
  73
  74   char *spargv[9];
  75   TEST_VERIFY_EXIT (((argc - 1) + 3) < array_length (spargv));
  76   int i = 0;
  77   for (; i < argc - 1; i++)
  78     spargv[i] = argv[i + 1];
  79   spargv[i++] = (char *) "--direct";
  80   spargv[i++] = (char *) "--restart";
  81   spargv[i] = NULL;
  82
  83   setenv ("LD_AUDIT", "tst-auditmod23.so", 0);
  84   struct support_capture_subprocess result
  85     = support_capture_subprogram (spargv[0], spargv);
  86   support_capture_subprocess_check (&result, "tst-audit22", 0, sc_allow_stderr);
  87
  88   /* The expected la_objopen/la_objclose:
  89      1. executable
  90      2. loader
  91      3. libc.so
  92      4. tst-audit23mod.so
  93      5. libc.so (LM_ID_NEWLM).
  94      6. vdso (optional and ignored).  */
  95   enum { max_objs = 6 };
  96   struct la_obj_t
  97   {
  98     char *lname;
  99     uintptr_t laddr;
 100     Lmid_t lmid;
 101     uintptr_t cookie;
 102     uintptr_t namespace;
 103     bool closed;
 104   } objs[max_objs] = { [0 ... max_objs-1] = { .closed = false } };
 105   size_t nobjs = 0;
 106
 107   /* The expected namespaces are one for the audit module, one for the
 108      application, and another for the dlmopen on handle_restart.  */
 109   enum { max_ns = 3 };
 110   uintptr_t acts[max_ns] = { 0 };
 111   size_t nacts = 0;
 112   int last_act = -1;
 113   uintptr_t last_act_cookie = -1;
 114   bool seen_first_objclose = false;
 115
 116   FILE *out = fmemopen (result.err.buffer, result.err.length, "r");
 117   TEST_VERIFY (out != NULL);
 118   char *buffer = NULL;
 119   size_t buffer_length = 0;
 120   while (xgetline (&buffer, &buffer_length, out))
 121     {
 122       *strchrnul (buffer, '\n') = '\0';
 123       printf ("info: subprocess output: %s\n", buffer);
 124
 125       if (startswith (buffer, "la_activity: "))
 126         {
 127           uintptr_t cookie;
 128           int this_act;
 129           int r = sscanf (buffer, "la_activity: %d %"SCNxPTR"", &this_act,
 130                           &cookie);
 131           TEST_COMPARE (r, 2);
 132
 133           if (this_act == LA_ACT_ADD && acts[nacts] != cookie)
 134             {
 135               /* The cookie identifies the object at the head of the
 136                  link map, so we only add a new namespace if it
 137                  changes from the previous one.  This works since
 138                  dlmopen is the last in the test body.  */
 139               if (cookie != last_act_cookie && last_act_cookie != -1)
 140                 TEST_COMPARE (last_act, LA_ACT_CONSISTENT);
 141
 142               acts[nacts++] = cookie;
 143               last_act_cookie = cookie;
 144             }
 145           /* LA_ACT_DELETE is called multiple times for each
 146              namespace, depending on destruction order.  */
 147           else if (this_act == LA_ACT_DELETE)
 148             last_act_cookie = cookie;
 149           else if (this_act == LA_ACT_CONSISTENT)
 150             {
 151               TEST_COMPARE (cookie, last_act_cookie);
 152               last_act_cookie = -1;
 153
 154               /* LA_ACT_DELETE must always be followed by an la_objclose.  */
 155               if (last_act == LA_ACT_DELETE)
 156                 TEST_COMPARE (seen_first_objclose, true);
 157               else
 158                 TEST_COMPARE (last_act, LA_ACT_ADD);
 159             }
 160
 161           last_act = this_act;
 162           seen_first_objclose = false;
 163         }
 164       else if (startswith (buffer, "la_objopen: "))
 165         {
 166           char *lname;
 167           uintptr_t laddr;
 168           Lmid_t lmid;
 169           uintptr_t cookie;
 170           int r = sscanf (buffer, "la_objopen: %"SCNxPTR"  %ms %"SCNxPTR" %ld",
 171                           &cookie, &lname, &laddr, &lmid);
 172           TEST_COMPARE (r, 4);
 173
 174           /* la_objclose is not triggered by vDSO because glibc does not
 175              unload it.  */
 176           if (is_vdso (lname))
 177             continue;
 178           if (nobjs == max_objs)
 179             FAIL_EXIT1 ("non expected la_objopen: %s %"PRIxPTR" %ld",
 180                         lname, laddr, lmid);
 181           objs[nobjs].lname = lname;
 182           objs[nobjs].laddr = laddr;
 183           objs[nobjs].lmid = lmid;
 184           objs[nobjs].cookie = cookie;
 185           objs[nobjs].namespace = last_act_cookie;
 186           objs[nobjs].closed = false;
 187           nobjs++;
 188
 189           /* This indirectly checks that la_objopen always comes before
 190              la_objclose btween la_activity calls.  */
 191           seen_first_objclose = false;
 192         }
 193       else if (startswith (buffer, "la_objclose: "))
 194         {
 195           char *lname;
 196           uintptr_t laddr;
 197           Lmid_t lmid;
 198           uintptr_t cookie;
 199           int r = sscanf (buffer, "la_objclose: %"SCNxPTR" %ms %"SCNxPTR" %ld",
 200                           &cookie, &lname, &laddr, &lmid);
 201           TEST_COMPARE (r, 4);
 202
 203           for (size_t i = 0; i < nobjs; i++)
 204             {
 205               if (strcmp (lname, objs[i].lname) == 0 && lmid == objs[i].lmid)
 206                 {
 207                   TEST_COMPARE (objs[i].closed, false);
 208                   TEST_COMPARE (objs[i].cookie, cookie);
 209                   if (objs[i].namespace == -1)
 210                     /* No LA_ACT_ADD before the first la_objopen call.  */
 211                     TEST_COMPARE (acts[0], last_act_cookie);
 212                   else
 213                     TEST_COMPARE (objs[i].namespace, last_act_cookie);
 214                   objs[i].closed = true;
 215                   break;
 216                 }
 217             }
 218
 219           /* la_objclose should be called after la_activity(LA_ACT_DELETE) for
 220              the closed object's namespace.  */
 221           TEST_COMPARE (last_act, LA_ACT_DELETE);
 222           seen_first_objclose = true;
 223         }
 224     }
 225
 226   for (size_t i = 0; i < nobjs; i++)
 227     {
 228       TEST_COMPARE (objs[i].closed, true);
 229       free (objs[i].lname);
 230     }
 231
 232   /* la_activity(LA_ACT_CONSISTENT) should be the last callback received.
 233      Since only one link map may be not-CONSISTENT at a time, this also
 234      ensures la_activity(LA_ACT_CONSISTENT) is the last callback received
 235      for every namespace.  */
 236   TEST_COMPARE (last_act, LA_ACT_CONSISTENT);
 237
 238   free (buffer);
 239   xfclose (out);
 240
 241   return 0;
 242 }
 243
 244 #define TEST_FUNCTION_ARGV do_test
 245 #include <support/test-driver.c>