1 | /* Stack executability handling for GNU dynamic linker. Hurd version. |
2 | Copyright (C) 2004-2022 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 | #include <ldsodefs.h> |
20 | #include <hurdstartup.h> |
21 | #include <errno.h> |
22 | |
23 | extern struct hurd_startup_data *_dl_hurd_data attribute_hidden; |
24 | |
25 | /* There is no portable way to know the bounds of the initial thread's stack |
26 | so as to mprotect it. */ |
27 | |
28 | int |
29 | _dl_make_stack_executable (void **stack_endp) |
30 | { |
31 | /* Challenge the caller. */ |
32 | if (__builtin_expect (*stack_endp != __libc_stack_end, 0)) |
33 | return EPERM; |
34 | *stack_endp = NULL; |
35 | |
36 | #if IS_IN (rtld) |
37 | if (__mprotect ((void *)_dl_hurd_data->stack_base, _dl_hurd_data->stack_size, |
38 | PROT_READ|PROT_WRITE|PROT_EXEC) != 0) |
39 | return errno; |
40 | |
41 | /* Remember that we changed the permission. */ |
42 | GL(dl_stack_flags) |= PF_X; |
43 | |
44 | return 0; |
45 | #else |
46 | /* We don't bother to implement this for static linking. */ |
47 | return ENOSYS; |
48 | #endif |
49 | } |
50 | rtld_hidden_def (_dl_make_stack_executable) |
51 | |