| 1 | /* Support for STV_PROTECTED visibility. Generic version. |
| 2 | Copyright (C) 2021-2022 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 | #ifndef _DL_PROTECTED_H |
| 20 | #define _DL_PROTECTED_H |
| 21 | |
| 22 | static inline void __attribute__ ((always_inline)) |
| 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 | |