1 /* Support for STV_PROTECTED visibility. Generic version.
2 Copyright (C) 2021 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 #ifndef _DL_PROTECTED_H
20 #define _DL_PROTECTED_H
21
22 static inline void __attribute__ ((always_inline))
_dl_check_protected_symbol(const char * undef_name,const struct link_map * undef_map,const ElfW (Sym)* ref,const struct link_map * map,int type_class)23 _dl_check_protected_symbol (const char *undef_name,
24 const struct link_map *undef_map,
25 const ElfW(Sym) *ref,
26 const struct link_map *map,
27 int type_class)
28 {
29 if (undef_map != NULL
30 && undef_map->l_type == lt_executable
31 && !(undef_map->l_1_needed
32 & GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS)
33 && (map->l_1_needed
34 & GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS))
35 {
36 if ((type_class & ELF_RTYPE_CLASS_COPY))
37 /* Disallow copy relocations in executable against protected
38 data symbols in a shared object which needs indirect external
39 access. */
40 _dl_signal_error (0, map->l_name, undef_name,
41 N_("copy relocation against non-copyable protected symbol"));
42 else if (ref->st_value != 0
43 && ref->st_shndx == SHN_UNDEF
44 && (type_class & ELF_RTYPE_CLASS_PLT))
45 /* Disallow non-zero symbol values of undefined symbols in
46 executable, which are used as the function pointer, against
47 protected function symbols in a shared object with indirect
48 external access. */
49 _dl_signal_error (0, map->l_name, undef_name,
50 N_("non-canonical reference to canonical protected function"));
51 }
52 }
53
54 #endif /* _DL_PROTECTED_H */
55