elf: Add la_activity during application exit

la_activity is not called during application exit, even though
la_objclose is.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>

1 files changed, 239 insertions, 0 deletions

diff --git a/elf/tst-audit23.c b/elf/tst-audit23.c
new file mode 100644
index 0000000000..4904cf1340
--- /dev/null
+++ b/elf/tst-audit23.c
@@ -0,0 +1,239 @@
+/* Check for expected la_objopen and la_objeclose for all objects.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <array_length.h>
+#include <errno.h>
+#include <getopt.h>
+#include <link.h>
+#include <limits.h>
+#include <inttypes.h>
+#include <gnu/lib-names.h>
+#include <string.h>
+#include <stdlib.h>
+#include <support/capture_subprocess.h>
+#include <support/check.h>
+#include <support/xstdio.h>
+#include <support/xdlfcn.h>
+#include <support/support.h>
+
+static int restart;
+#define CMDLINE_OPTIONS \
+  { "restart", no_argument, &restart, 1 },
+
+static int
+handle_restart (void)
+{
+  xdlopen ("tst-audit23mod.so", RTLD_NOW);
+  xdlmopen (LM_ID_NEWLM, LIBC_SO, RTLD_NOW);
+
+  return 0;
+}
+
+static inline bool
+startswith (const char *str, const char *pre)
+{
+  size_t lenpre = strlen (pre);
+  size_t lenstr = strlen (str);
+  return lenstr >= lenpre && memcmp (pre, str, lenpre) == 0;
+}
+
+static inline bool
+is_vdso (const char *str)
+{
+  return startswith (str, "linux-gate")
+	 || startswith (str, "linux-vdso");
+}
+
+static int
+do_test (int argc, char *argv[])
+{
+  /* We must have either:
+     - One or four parameters left if called initially:
+       + path to ld.so         optional
+       + "--library-path"      optional
+       + the library path      optional
+       + the application name  */
+  if (restart)
+    return handle_restart ();
+
+  char *spargv[9];
+  TEST_VERIFY_EXIT (((argc - 1) + 3) < array_length (spargv));
+  int i = 0;
+  for (; i < argc - 1; i++)
+    spargv[i] = argv[i + 1];
+  spargv[i++] = (char *) "--direct";
+  spargv[i++] = (char *) "--restart";
+  spargv[i] = NULL;
+
+  setenv ("LD_AUDIT", "tst-auditmod23.so", 0);
+  struct support_capture_subprocess result
+    = support_capture_subprogram (spargv[0], spargv);
+  support_capture_subprocess_check (&result, "tst-audit22", 0, sc_allow_stderr);
+
+  /* The expected la_objopen/la_objclose:
+     1. executable
+     2. loader
+     3. libc.so
+     4. tst-audit23mod.so
+     5. libc.so (LM_ID_NEWLM).
+     6. vdso (optional and ignored).  */
+  enum { max_objs = 6 };
+  struct la_obj_t
+  {
+    char *lname;
+    uintptr_t laddr;
+    Lmid_t lmid;
+    bool closed;
+  } objs[max_objs] = { [0 ... max_objs-1] = { .closed = false } };
+  size_t nobjs = 0;
+
+  /* The expected namespaces are one for the audit module, one for the
+     application, and another for the dlmopen on handle_restart.  */
+  enum { max_ns = 3 };
+  uintptr_t acts[max_ns] = { 0 };
+  size_t nacts = 0;
+  int last_act = -1;
+  uintptr_t last_act_cookie = -1;
+  bool seen_first_objclose = false;
+
+  FILE *out = fmemopen (result.err.buffer, result.err.length, "r");
+  TEST_VERIFY (out != NULL);
+  char *buffer = NULL;
+  size_t buffer_length = 0;
+  while (xgetline (&buffer, &buffer_length, out))
+    {
+      if (startswith (buffer, "la_activity: "))
+	{
+	  uintptr_t cookie;
+	  int this_act;
+	  int r = sscanf (buffer, "la_activity: %d %"SCNxPTR"", &this_act,
+			  &cookie);
+	  TEST_COMPARE (r, 2);
+
+	  /* The cookie identifies the object at the head of the link map,
+	     so we only add a new namespace if it changes from the previous
+	     one.  This works since dlmopen is the last in the test body.  */
+	  if (cookie != last_act_cookie && last_act_cookie != -1)
+	    TEST_COMPARE (last_act, LA_ACT_CONSISTENT);
+
+	  if (this_act == LA_ACT_ADD && acts[nacts] != cookie)
+	    {
+	      acts[nacts++] = cookie;
+	      last_act_cookie = cookie;
+	    }
+	  /* The LA_ACT_DELETE is called in the reverse order of LA_ACT_ADD
+	     at program termination (if the tests adds a dlclose or a library
+	     with extra dependencies this will need to be adapted).  */
+	  else if (this_act == LA_ACT_DELETE)
+	    {
+	      last_act_cookie = acts[--nacts];
+	      TEST_COMPARE (acts[nacts], cookie);
+	      acts[nacts] = 0;
+	    }
+	  else if (this_act == LA_ACT_CONSISTENT)
+	    {
+	      TEST_COMPARE (cookie, last_act_cookie);
+
+	      /* LA_ACT_DELETE must always be followed by an la_objclose.  */
+	      if (last_act == LA_ACT_DELETE)
+		TEST_COMPARE (seen_first_objclose, true);
+	      else
+		TEST_COMPARE (last_act, LA_ACT_ADD);
+	    }
+
+	  last_act = this_act;
+	  seen_first_objclose = false;
+	}
+      else if (startswith (buffer, "la_objopen: "))
+	{
+	  char *lname;
+	  uintptr_t laddr;
+	  Lmid_t lmid;
+	  uintptr_t cookie;
+	  int r = sscanf (buffer, "la_objopen: %"SCNxPTR"  %ms %"SCNxPTR" %ld",
+			  &cookie, &lname, &laddr, &lmid);
+	  TEST_COMPARE (r, 4);
+
+	  /* la_objclose is not triggered by vDSO because glibc does not
+	     unload it.  */
+	  if (is_vdso (lname))
+	    continue;
+	  if (nobjs == max_objs)
+	    FAIL_EXIT1 ("non expected la_objopen: %s %"PRIxPTR" %ld",
+			lname, laddr, lmid);
+	  objs[nobjs].lname = lname;
+	  objs[nobjs].laddr = laddr;
+	  objs[nobjs].lmid = lmid;
+	  objs[nobjs].closed = false;
+	  nobjs++;
+
+	  /* This indirectly checks that la_objopen always comes before
+	     la_objclose btween la_activity calls.  */
+	  seen_first_objclose = false;
+	}
+      else if (startswith (buffer, "la_objclose: "))
+	{
+	  char *lname;
+	  uintptr_t laddr;
+	  Lmid_t lmid;
+	  uintptr_t cookie;
+	  int r = sscanf (buffer, "la_objclose: %"SCNxPTR" %ms %"SCNxPTR" %ld",
+			  &cookie, &lname, &laddr, &lmid);
+	  TEST_COMPARE (r, 4);
+
+	  for (size_t i = 0; i < nobjs; i++)
+	    {
+	      if (strcmp (lname, objs[i].lname) == 0 && lmid == objs[i].lmid)
+		{
+		  TEST_COMPARE (objs[i].closed, false);
+		  objs[i].closed = true;
+		  break;
+		}
+	    }
+
+	  /* la_objclose should be called after la_activity(LA_ACT_DELETE) for
+	     the closed object's namespace.  */
+	  TEST_COMPARE (last_act, LA_ACT_DELETE);
+	  if (!seen_first_objclose)
+	    {
+	      TEST_COMPARE (last_act_cookie, cookie);
+	      seen_first_objclose = true;
+	    }
+	}
+    }
+
+  for (size_t i = 0; i < nobjs; i++)
+    {
+      TEST_COMPARE (objs[i].closed, true);
+      free (objs[i].lname);
+    }
+
+  /* la_activity(LA_ACT_CONSISTENT) should be the last callback received.
+     Since only one link map may be not-CONSISTENT at a time, this also
+     ensures la_activity(LA_ACT_CONSISTENT) is the last callback received
+     for every namespace.  */
+  TEST_COMPARE (last_act, LA_ACT_CONSISTENT);
+
+  free (buffer);
+  xfclose (out);
+
+  return 0;
+}
+
+#define TEST_FUNCTION_ARGV do_test
+#include <support/test-driver.c>