1/* Check DTAUDIT and vDSO interaction.
2 Copyright (C) 2021-2024 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 <link.h>
20#include <inttypes.h>
21#include <stdbool.h>
22#include <string.h>
23#include <stdio.h>
24#include <sys/auxv.h>
25
26static inline bool
27startswith (const char *str, const char *pre)
28{
29 size_t lenpre = strlen (s: pre);
30 size_t lenstr = strlen (s: str);
31 return lenstr < lenpre ? false : memcmp (s1: pre, s2: str, n: lenpre) == 0;
32}
33
34unsigned int
35la_version (unsigned int version)
36{
37 return LAV_CURRENT;
38}
39
40unsigned int
41la_objopen (struct link_map *map, Lmid_t lmid, uintptr_t *cookie)
42{
43 /* The linux-gate.so is placed at a fixed address, thus l_addr being 0,
44 and it might be the value reported as the AT_SYSINFO_EHDR. */
45 if (map->l_addr == 0 && startswith (str: map->l_name, pre: "linux-gate.so"))
46 fprintf (stderr, format: "vdso found: %p\n", NULL);
47 else if (map->l_addr == getauxval (AT_SYSINFO_EHDR))
48 fprintf (stderr, format: "vdso found: %p\n", (void*) map->l_addr);
49
50 return 0;
51}
52

source code of glibc/elf/tst-auditmod22.c