1 | /* Test if a memory region is wholly unwritable. Mach version. |
2 | Copyright (C) 2004-2024 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 <stdlib.h> |
20 | #include <stdint.h> |
21 | #include <mach.h> |
22 | |
23 | /* Return 1 if the whole area PTR .. PTR+SIZE is not writable. |
24 | Return -1 if it is writable. */ |
25 | |
26 | int |
27 | __readonly_area (const char *ptr, size_t size) |
28 | { |
29 | vm_address_t region_address = (uintptr_t) ptr; |
30 | vm_size_t region_length = size; |
31 | vm_prot_t protection; |
32 | vm_prot_t max_protection; |
33 | vm_inherit_t inheritance; |
34 | boolean_t is_shared; |
35 | mach_port_t object_name; |
36 | vm_offset_t offset; |
37 | |
38 | while (__vm_region (__mach_task_self (), |
39 | ®ion_address, ®ion_length, |
40 | &protection, &max_protection, &inheritance, &is_shared, |
41 | &object_name, &offset) == KERN_SUCCESS |
42 | && region_address <= (uintptr_t) ptr) |
43 | { |
44 | region_address += region_length; |
45 | if (region_address < (uintptr_t) ptr) |
46 | continue; |
47 | |
48 | if (protection & VM_PROT_WRITE) |
49 | return -1; |
50 | |
51 | if (region_address - (uintptr_t) ptr >= size) |
52 | break; |
53 | } |
54 | |
55 | return 1; |
56 | } |
57 | |