1 /* Check for expected la_objopen and la_objeclose for all objects.
2    Copyright (C) 2022 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
handle_restart(void)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
startswith(const char * str,const char * pre)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
is_vdso(const char * str)56 is_vdso (const char *str)
57 {
58   return startswith (str, "linux-gate")
59 	 || startswith (str, "linux-vdso");
60 }
61 
62 static int
do_test(int argc,char * argv[])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     bool closed;
102   } objs[max_objs] = { [0 ... max_objs-1] = { .closed = false } };
103   size_t nobjs = 0;
104 
105   /* The expected namespaces are one for the audit module, one for the
106      application, and another for the dlmopen on handle_restart.  */
107   enum { max_ns = 3 };
108   uintptr_t acts[max_ns] = { 0 };
109   size_t nacts = 0;
110   int last_act = -1;
111   uintptr_t last_act_cookie = -1;
112   bool seen_first_objclose = false;
113 
114   FILE *out = fmemopen (result.err.buffer, result.err.length, "r");
115   TEST_VERIFY (out != NULL);
116   char *buffer = NULL;
117   size_t buffer_length = 0;
118   while (xgetline (&buffer, &buffer_length, out))
119     {
120       if (startswith (buffer, "la_activity: "))
121 	{
122 	  uintptr_t cookie;
123 	  int this_act;
124 	  int r = sscanf (buffer, "la_activity: %d %"SCNxPTR"", &this_act,
125 			  &cookie);
126 	  TEST_COMPARE (r, 2);
127 
128 	  /* The cookie identifies the object at the head of the link map,
129 	     so we only add a new namespace if it changes from the previous
130 	     one.  This works since dlmopen is the last in the test body.  */
131 	  if (cookie != last_act_cookie && last_act_cookie != -1)
132 	    TEST_COMPARE (last_act, LA_ACT_CONSISTENT);
133 
134 	  if (this_act == LA_ACT_ADD && acts[nacts] != cookie)
135 	    {
136 	      acts[nacts++] = cookie;
137 	      last_act_cookie = cookie;
138 	    }
139 	  /* The LA_ACT_DELETE is called in the reverse order of LA_ACT_ADD
140 	     at program termination (if the tests adds a dlclose or a library
141 	     with extra dependencies this will need to be adapted).  */
142 	  else if (this_act == LA_ACT_DELETE)
143 	    {
144 	      last_act_cookie = acts[--nacts];
145 	      TEST_COMPARE (acts[nacts], cookie);
146 	      acts[nacts] = 0;
147 	    }
148 	  else if (this_act == LA_ACT_CONSISTENT)
149 	    {
150 	      TEST_COMPARE (cookie, last_act_cookie);
151 
152 	      /* LA_ACT_DELETE must always be followed by an la_objclose.  */
153 	      if (last_act == LA_ACT_DELETE)
154 		TEST_COMPARE (seen_first_objclose, true);
155 	      else
156 		TEST_COMPARE (last_act, LA_ACT_ADD);
157 	    }
158 
159 	  last_act = this_act;
160 	  seen_first_objclose = false;
161 	}
162       else if (startswith (buffer, "la_objopen: "))
163 	{
164 	  char *lname;
165 	  uintptr_t laddr;
166 	  Lmid_t lmid;
167 	  uintptr_t cookie;
168 	  int r = sscanf (buffer, "la_objopen: %"SCNxPTR"  %ms %"SCNxPTR" %ld",
169 			  &cookie, &lname, &laddr, &lmid);
170 	  TEST_COMPARE (r, 4);
171 
172 	  /* la_objclose is not triggered by vDSO because glibc does not
173 	     unload it.  */
174 	  if (is_vdso (lname))
175 	    continue;
176 	  if (nobjs == max_objs)
177 	    FAIL_EXIT1 ("non expected la_objopen: %s %"PRIxPTR" %ld",
178 			lname, laddr, lmid);
179 	  objs[nobjs].lname = lname;
180 	  objs[nobjs].laddr = laddr;
181 	  objs[nobjs].lmid = lmid;
182 	  objs[nobjs].closed = false;
183 	  nobjs++;
184 
185 	  /* This indirectly checks that la_objopen always comes before
186 	     la_objclose btween la_activity calls.  */
187 	  seen_first_objclose = false;
188 	}
189       else if (startswith (buffer, "la_objclose: "))
190 	{
191 	  char *lname;
192 	  uintptr_t laddr;
193 	  Lmid_t lmid;
194 	  uintptr_t cookie;
195 	  int r = sscanf (buffer, "la_objclose: %"SCNxPTR" %ms %"SCNxPTR" %ld",
196 			  &cookie, &lname, &laddr, &lmid);
197 	  TEST_COMPARE (r, 4);
198 
199 	  for (size_t i = 0; i < nobjs; i++)
200 	    {
201 	      if (strcmp (lname, objs[i].lname) == 0 && lmid == objs[i].lmid)
202 		{
203 		  TEST_COMPARE (objs[i].closed, false);
204 		  objs[i].closed = true;
205 		  break;
206 		}
207 	    }
208 
209 	  /* la_objclose should be called after la_activity(LA_ACT_DELETE) for
210 	     the closed object's namespace.  */
211 	  TEST_COMPARE (last_act, LA_ACT_DELETE);
212 	  if (!seen_first_objclose)
213 	    {
214 	      TEST_COMPARE (last_act_cookie, cookie);
215 	      seen_first_objclose = true;
216 	    }
217 	}
218     }
219 
220   for (size_t i = 0; i < nobjs; i++)
221     {
222       TEST_COMPARE (objs[i].closed, true);
223       free (objs[i].lname);
224     }
225 
226   /* la_activity(LA_ACT_CONSISTENT) should be the last callback received.
227      Since only one link map may be not-CONSISTENT at a time, this also
228      ensures la_activity(LA_ACT_CONSISTENT) is the last callback received
229      for every namespace.  */
230   TEST_COMPARE (last_act, LA_ACT_CONSISTENT);
231 
232   free (buffer);
233   xfclose (out);
234 
235   return 0;
236 }
237 
238 #define TEST_FUNCTION_ARGV do_test
239 #include <support/test-driver.c>
240