1 /*
2 * Stack-less Just-In-Time compiler
3 *
4 * Copyright Zoltan Herczeg (hzmester@freemail.hu). All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without modification, are
7 * permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright notice, this list of
10 * conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
13 * of conditions and the following disclaimer in the documentation and/or other materials
14 * provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
19 * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
21 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
22 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
24 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <sys/types.h>
28 #include <sys/mman.h>
29 /*
30 On macOS systems, returns MAP_JIT if it is defined _and_ we're running on a
31 version where it's OK to have more than one JIT block or where MAP_JIT is
32 required.
33 On non-macOS systems, returns MAP_JIT if it is defined.
34 */
35 #include <TargetConditionals.h>
36
37 #if (defined(TARGET_OS_OSX) && TARGET_OS_OSX) || (TARGET_OS_MAC && !TARGET_OS_IPHONE)
38
39 #if defined(SLJIT_CONFIG_X86) && SLJIT_CONFIG_X86
40
41 #include <sys/utsname.h>
42 #include <stdlib.h>
43
44 #define SLJIT_MAP_JIT (get_map_jit_flag())
45 #define SLJIT_UPDATE_WX_FLAGS(from, to, enable_exec)
46
get_map_jit_flag(void)47 static SLJIT_INLINE int get_map_jit_flag(void)
48 {
49 size_t page_size;
50 void *ptr;
51 struct utsname name;
52 static int map_jit_flag = -1;
53
54 if (map_jit_flag < 0) {
55 map_jit_flag = 0;
56 uname(&name);
57
58 /* Kernel version for 10.14.0 (Mojave) or later */
59 if (atoi(name.release) >= 18) {
60 page_size = get_page_alignment() + 1;
61 /* Only use MAP_JIT if a hardened runtime is used */
62 ptr = mmap(NULL, page_size, PROT_WRITE | PROT_EXEC,
63 MAP_PRIVATE | MAP_ANON, -1, 0);
64
65 if (ptr != MAP_FAILED)
66 munmap(ptr, page_size);
67 else
68 map_jit_flag = MAP_JIT;
69 }
70 }
71 return map_jit_flag;
72 }
73
74 #elif defined(SLJIT_CONFIG_ARM) && SLJIT_CONFIG_ARM
75
76 #include <AvailabilityMacros.h>
77 #include <pthread.h>
78
79 #define SLJIT_MAP_JIT (MAP_JIT)
80 #define SLJIT_UPDATE_WX_FLAGS(from, to, enable_exec) \
81 apple_update_wx_flags(enable_exec)
82
apple_update_wx_flags(sljit_s32 enable_exec)83 static SLJIT_INLINE void apple_update_wx_flags(sljit_s32 enable_exec)
84 {
85 #if MAC_OS_X_VERSION_MIN_REQUIRED < 110000
86 if (__builtin_available(macos 11, *))
87 #endif /* BigSur */
88 pthread_jit_write_protect_np(enable_exec);
89 }
90
91 #elif defined(SLJIT_CONFIG_PPC) && SLJIT_CONFIG_PPC
92
93 #define SLJIT_MAP_JIT (0)
94 #define SLJIT_UPDATE_WX_FLAGS(from, to, enable_exec)
95
96 #else
97 #error "Unsupported architecture"
98 #endif /* SLJIT_CONFIG */
99
100 #else /* !TARGET_OS_OSX */
101
102 #ifdef MAP_JIT
103 #define SLJIT_MAP_JIT (MAP_JIT)
104 #else
105 #define SLJIT_MAP_JIT (0)
106 #endif
107
108 #endif /* TARGET_OS_OSX */
109
alloc_chunk(sljit_uw size)110 static SLJIT_INLINE void* alloc_chunk(sljit_uw size)
111 {
112 void *retval;
113 int prot = PROT_READ | PROT_WRITE | PROT_EXEC;
114 int flags = MAP_PRIVATE;
115 int fd = -1;
116
117 flags |= MAP_ANON | SLJIT_MAP_JIT;
118
119 retval = mmap(NULL, size, prot, flags, fd, 0);
120 if (retval == MAP_FAILED)
121 return NULL;
122
123 SLJIT_UPDATE_WX_FLAGS(retval, (uint8_t *)retval + size, 0);
124
125 return retval;
126 }
127
free_chunk(void * chunk,sljit_uw size)128 static SLJIT_INLINE void free_chunk(void *chunk, sljit_uw size)
129 {
130 munmap(chunk, size);
131 }
132
133 #include "sljitExecAllocatorCore.c"
134
