| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame] | 1 | /* Check whether caller comes from the right place. |
| 2 | Copyright (C) 2004-2016 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 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <assert.h> |
| 20 | #include <ldsodefs.h> |
| 21 | #include <stddef.h> |
| 22 | #include <caller.h> |
| 23 | #include <gnu/lib-names.h> |
| 24 | |
| 25 | |
| 26 | int |
| 27 | attribute_hidden |
| 28 | _dl_check_caller (const void *caller, enum allowmask mask) |
| 29 | { |
| 30 | static const char expected1[] = LIBC_SO; |
| 31 | static const char expected2[] = LIBDL_SO; |
| 32 | #ifdef LIBPTHREAD_SO |
| 33 | static const char expected3[] = LIBPTHREAD_SO; |
| 34 | #endif |
| 35 | static const char expected4[] = LD_SO; |
| 36 | |
| 37 | for (Lmid_t ns = 0; ns < GL(dl_nns); ++ns) |
| 38 | for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l != NULL; |
| 39 | l = l->l_next) |
| 40 | if (caller >= (const void *) l->l_map_start |
| 41 | && caller < (const void *) l->l_text_end) |
| 42 | { |
| 43 | /* The address falls into this DSO's address range. Check the |
| 44 | name. */ |
| 45 | if ((mask & allow_libc) && strcmp (expected1, l->l_name) == 0) |
| 46 | return 0; |
| 47 | if ((mask & allow_libdl) && strcmp (expected2, l->l_name) == 0) |
| 48 | return 0; |
| 49 | #ifdef LIBPTHREAD_SO |
| 50 | if ((mask & allow_libpthread) && strcmp (expected3, l->l_name) == 0) |
| 51 | return 0; |
| 52 | #endif |
| 53 | if ((mask & allow_ldso) && strcmp (expected4, l->l_name) == 0) |
| 54 | return 0; |
| 55 | |
| 56 | struct libname_list *runp = l->l_libname; |
| 57 | |
| 58 | while (runp != NULL) |
| 59 | { |
| 60 | if ((mask & allow_libc) && strcmp (expected1, runp->name) == 0) |
| 61 | return 0; |
| 62 | if ((mask & allow_libdl) && strcmp (expected2, runp->name) == 0) |
| 63 | return 0; |
| 64 | #ifdef LIBPTHREAD_SO |
| 65 | if ((mask & allow_libpthread) |
| 66 | && strcmp (expected3, runp->name) == 0) |
| 67 | return 0; |
| 68 | #endif |
| 69 | if ((mask & allow_ldso) && strcmp (expected4, runp->name) == 0) |
| 70 | return 0; |
| 71 | |
| 72 | runp = runp->next; |
| 73 | } |
| 74 | |
| 75 | break; |
| 76 | } |
| 77 | |
| 78 | /* Maybe the dynamic linker is not yet on the list. */ |
| 79 | if ((mask & allow_ldso) != 0 |
| 80 | && caller >= (const void *) GL(dl_rtld_map).l_map_start |
| 81 | && caller < (const void *) GL(dl_rtld_map).l_text_end) |
| 82 | return 0; |
| 83 | |
| 84 | /* No valid caller. */ |
| 85 | return 1; |
| 86 | } |