1 //===-- asan_mapping.h ------------------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of AddressSanitizer, an address sanity checker.
12 // Defines ASan memory mapping.
13 //===----------------------------------------------------------------------===//
14 #ifndef ASAN_MAPPING_H
15 #define ASAN_MAPPING_H
17 #include "asan_internal.h"
19 // The full explanation of the memory mapping could be found here:
20 // https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm
22 // Typical shadow mapping on Linux/x86_64 with SHADOW_OFFSET == 0x00007fff8000:
23 // || `[0x10007fff8000, 0x7fffffffffff]` || HighMem ||
24 // || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow ||
25 // || `[0x00008fff7000, 0x02008fff6fff]` || ShadowGap ||
26 // || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow ||
27 // || `[0x000000000000, 0x00007fff7fff]` || LowMem ||
29 // When SHADOW_OFFSET is zero (-pie):
30 // || `[0x100000000000, 0x7fffffffffff]` || HighMem ||
31 // || `[0x020000000000, 0x0fffffffffff]` || HighShadow ||
32 // || `[0x000000040000, 0x01ffffffffff]` || ShadowGap ||
34 // Special case when something is already mapped between
35 // 0x003000000000 and 0x005000000000 (e.g. when prelink is installed):
36 // || `[0x10007fff8000, 0x7fffffffffff]` || HighMem ||
37 // || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow ||
38 // || `[0x005000000000, 0x02008fff6fff]` || ShadowGap3 ||
39 // || `[0x003000000000, 0x004fffffffff]` || MidMem ||
40 // || `[0x000a7fff8000, 0x002fffffffff]` || ShadowGap2 ||
41 // || `[0x00067fff8000, 0x000a7fff7fff]` || MidShadow ||
42 // || `[0x00008fff7000, 0x00067fff7fff]` || ShadowGap ||
43 // || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow ||
44 // || `[0x000000000000, 0x00007fff7fff]` || LowMem ||
46 // Default Linux/i386 mapping on x86_64 machine:
47 // || `[0x40000000, 0xffffffff]` || HighMem ||
48 // || `[0x28000000, 0x3fffffff]` || HighShadow ||
49 // || `[0x24000000, 0x27ffffff]` || ShadowGap ||
50 // || `[0x20000000, 0x23ffffff]` || LowShadow ||
51 // || `[0x00000000, 0x1fffffff]` || LowMem ||
53 // Default Linux/i386 mapping on i386 machine
54 // (addresses starting with 0xc0000000 are reserved
55 // for kernel and thus not sanitized):
56 // || `[0x38000000, 0xbfffffff]` || HighMem ||
57 // || `[0x27000000, 0x37ffffff]` || HighShadow ||
58 // || `[0x24000000, 0x26ffffff]` || ShadowGap ||
59 // || `[0x20000000, 0x23ffffff]` || LowShadow ||
60 // || `[0x00000000, 0x1fffffff]` || LowMem ||
62 // Default Linux/MIPS32 mapping:
63 // || `[0x2aaa0000, 0xffffffff]` || HighMem ||
64 // || `[0x0fff4000, 0x2aa9ffff]` || HighShadow ||
65 // || `[0x0bff4000, 0x0fff3fff]` || ShadowGap ||
66 // || `[0x0aaa0000, 0x0bff3fff]` || LowShadow ||
67 // || `[0x00000000, 0x0aa9ffff]` || LowMem ||
69 // Default Linux/MIPS64 mapping:
70 // || `[0x4000000000, 0xffffffffff]` || HighMem ||
71 // || `[0x2800000000, 0x3fffffffff]` || HighShadow ||
72 // || `[0x2400000000, 0x27ffffffff]` || ShadowGap ||
73 // || `[0x2000000000, 0x23ffffffff]` || LowShadow ||
74 // || `[0x0000000000, 0x1fffffffff]` || LowMem ||
76 // Default Linux/AArch64 (39-bit VMA) mapping:
77 // || `[0x2000000000, 0x7fffffffff]` || highmem ||
78 // || `[0x1400000000, 0x1fffffffff]` || highshadow ||
79 // || `[0x1200000000, 0x13ffffffff]` || shadowgap ||
80 // || `[0x1000000000, 0x11ffffffff]` || lowshadow ||
81 // || `[0x0000000000, 0x0fffffffff]` || lowmem ||
83 // Default Linux/AArch64 (42-bit VMA) mapping:
84 // || `[0x10000000000, 0x3ffffffffff]` || highmem ||
85 // || `[0x0a000000000, 0x0ffffffffff]` || highshadow ||
86 // || `[0x09000000000, 0x09fffffffff]` || shadowgap ||
87 // || `[0x08000000000, 0x08fffffffff]` || lowshadow ||
88 // || `[0x00000000000, 0x07fffffffff]` || lowmem ||
90 // Default Linux/S390 mapping:
91 // || `[0x30000000, 0x7fffffff]` || HighMem ||
92 // || `[0x26000000, 0x2fffffff]` || HighShadow ||
93 // || `[0x24000000, 0x25ffffff]` || ShadowGap ||
94 // || `[0x20000000, 0x23ffffff]` || LowShadow ||
95 // || `[0x00000000, 0x1fffffff]` || LowMem ||
97 // Default Linux/SystemZ mapping:
98 // || `[0x14000000000000, 0x1fffffffffffff]` || HighMem ||
99 // || `[0x12800000000000, 0x13ffffffffffff]` || HighShadow ||
100 // || `[0x12000000000000, 0x127fffffffffff]` || ShadowGap ||
101 // || `[0x10000000000000, 0x11ffffffffffff]` || LowShadow ||
102 // || `[0x00000000000000, 0x0fffffffffffff]` || LowMem ||
104 // Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:
105 // || `[0x500000000000, 0x7fffffffffff]` || HighMem ||
106 // || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow ||
107 // || `[0x480000000000, 0x49ffffffffff]` || ShadowGap ||
108 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||
109 // || `[0x000000000000, 0x3fffffffffff]` || LowMem ||
111 // Shadow mapping on FreeBSD/i386 with SHADOW_OFFSET == 0x40000000:
112 // || `[0x60000000, 0xffffffff]` || HighMem ||
113 // || `[0x4c000000, 0x5fffffff]` || HighShadow ||
114 // || `[0x48000000, 0x4bffffff]` || ShadowGap ||
115 // || `[0x40000000, 0x47ffffff]` || LowShadow ||
116 // || `[0x00000000, 0x3fffffff]` || LowMem ||
118 // Shadow mapping on NetBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:
119 // || `[0x4feffffffe01, 0x7f7ffffff000]` || HighMem ||
120 // || `[0x49fdffffffc0, 0x4feffffffe00]` || HighShadow ||
121 // || `[0x480000000000, 0x49fdffffffbf]` || ShadowGap ||
122 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||
123 // || `[0x000000000000, 0x3fffffffffff]` || LowMem ||
125 // Shadow mapping on NetBSD/i386 with SHADOW_OFFSET == 0x40000000:
126 // || `[0x60000000, 0xfffff000]` || HighMem ||
127 // || `[0x4c000000, 0x5fffffff]` || HighShadow ||
128 // || `[0x48000000, 0x4bffffff]` || ShadowGap ||
129 // || `[0x40000000, 0x47ffffff]` || LowShadow ||
130 // || `[0x00000000, 0x3fffffff]` || LowMem ||
132 // Default Windows/i386 mapping:
133 // (the exact location of HighShadow/HighMem may vary depending
134 // on WoW64, /LARGEADDRESSAWARE, etc).
135 // || `[0x50000000, 0xffffffff]` || HighMem ||
136 // || `[0x3a000000, 0x4fffffff]` || HighShadow ||
137 // || `[0x36000000, 0x39ffffff]` || ShadowGap ||
138 // || `[0x30000000, 0x35ffffff]` || LowShadow ||
139 // || `[0x00000000, 0x2fffffff]` || LowMem ||
141 // Shadow mapping on Myriad2 (for shadow scale 5):
142 // || `[0x9ff80000, 0x9fffffff]` || ShadowGap ||
143 // || `[0x9f000000, 0x9ff7ffff]` || LowShadow ||
144 // || `[0x80000000, 0x9effffff]` || LowMem ||
145 // || `[0x00000000, 0x7fffffff]` || Ignored ||
147 #if defined(ASAN_SHADOW_SCALE)
148 static const u64 kDefaultShadowScale = ASAN_SHADOW_SCALE;
150 static const u64 kDefaultShadowScale = SANITIZER_MYRIAD2 ? 5 : 3;
152 static const u64 kDefaultShadowSentinel = ~(uptr)0;
153 static const u64 kDefaultShadowOffset32 = 1ULL << 29; // 0x20000000
154 static const u64 kDefaultShadowOffset64 = 1ULL << 44;
155 static const u64 kDefaultShort64bitShadowOffset =
156 0x7FFFFFFF & (~0xFFFULL << kDefaultShadowScale); // < 2G.
157 static const u64 kIosShadowOffset32 = 1ULL << 30; // 0x40000000
158 static const u64 kIosShadowOffset64 = 0x120200000;
159 static const u64 kIosSimShadowOffset32 = 1ULL << 30;
160 static const u64 kIosSimShadowOffset64 = kDefaultShadowOffset64;
161 static const u64 kAArch64_ShadowOffset64 = 1ULL << 36;
162 static const u64 kMIPS32_ShadowOffset32 = 0x0aaa0000;
163 static const u64 kMIPS64_ShadowOffset64 = 1ULL << 37;
164 static const u64 kPPC64_ShadowOffset64 = 1ULL << 44;
165 static const u64 kSystemZ_ShadowOffset64 = 1ULL << 52;
166 static const u64 kFreeBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000
167 static const u64 kFreeBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000
168 static const u64 kNetBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000
169 static const u64 kNetBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000
170 static const u64 kWindowsShadowOffset32 = 3ULL << 28; // 0x30000000
172 static const u64 kMyriadMemoryOffset32 = 0x80000000ULL;
173 static const u64 kMyriadMemorySize32 = 0x20000000ULL;
174 static const u64 kMyriadMemoryEnd32 =
175 kMyriadMemoryOffset32 + kMyriadMemorySize32 - 1;
176 static const u64 kMyriadShadowOffset32 =
177 (kMyriadMemoryOffset32 + kMyriadMemorySize32 -
178 (kMyriadMemorySize32 >> kDefaultShadowScale));
179 static const u64 kMyriadCacheBitMask32 = 0x40000000ULL;
181 #define SHADOW_SCALE kDefaultShadowScale
183 #if SANITIZER_FUCHSIA
184 # define SHADOW_OFFSET (0)
185 #elif SANITIZER_WORDSIZE == 32
186 # if SANITIZER_ANDROID
187 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
188 # elif defined(__mips__)
189 # define SHADOW_OFFSET kMIPS32_ShadowOffset32
190 # elif SANITIZER_FREEBSD
191 # define SHADOW_OFFSET kFreeBSD_ShadowOffset32
192 # elif SANITIZER_NETBSD
193 # define SHADOW_OFFSET kNetBSD_ShadowOffset32
194 # elif SANITIZER_WINDOWS
195 # define SHADOW_OFFSET kWindowsShadowOffset32
197 # if SANITIZER_IOSSIM
198 # define SHADOW_OFFSET kIosSimShadowOffset32
200 # define SHADOW_OFFSET kIosShadowOffset32
202 # elif SANITIZER_MYRIAD2
203 # define SHADOW_OFFSET kMyriadShadowOffset32
205 # define SHADOW_OFFSET kDefaultShadowOffset32
209 # if SANITIZER_IOSSIM
210 # define SHADOW_OFFSET kIosSimShadowOffset64
212 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
214 # elif defined(__aarch64__)
215 # define SHADOW_OFFSET kAArch64_ShadowOffset64
216 # elif defined(__powerpc64__)
217 # define SHADOW_OFFSET kPPC64_ShadowOffset64
218 # elif defined(__s390x__)
219 # define SHADOW_OFFSET kSystemZ_ShadowOffset64
220 # elif SANITIZER_FREEBSD
221 # define SHADOW_OFFSET kFreeBSD_ShadowOffset64
222 # elif SANITIZER_NETBSD
223 # define SHADOW_OFFSET kNetBSD_ShadowOffset64
225 # define SHADOW_OFFSET kDefaultShadowOffset64
226 # elif defined(__mips64)
227 # define SHADOW_OFFSET kMIPS64_ShadowOffset64
228 # elif SANITIZER_WINDOWS64
229 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
231 # define SHADOW_OFFSET kDefaultShort64bitShadowOffset
235 #if SANITIZER_ANDROID && defined(__arm__)
236 # define ASAN_PREMAP_SHADOW 1
238 # define ASAN_PREMAP_SHADOW 0
241 #define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE)
243 #define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below.
245 #if DO_ASAN_MAPPING_PROFILE
246 # define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++;
248 # define PROFILE_ASAN_MAPPING()
251 // If 1, all shadow boundaries are constants.
252 // Don't set to 1 other than for testing.
253 #define ASAN_FIXED_MAPPING 0
257 extern uptr AsanMappingProfile[];
259 #if ASAN_FIXED_MAPPING
260 // Fixed mapping for 64-bit Linux. Mostly used for performance comparison
261 // with non-fixed mapping. As of r175253 (Feb 2013) the performance
262 // difference between fixed and non-fixed mapping is below the noise level.
263 static uptr kHighMemEnd = 0x7fffffffffffULL;
264 static uptr kMidMemBeg = 0x3000000000ULL;
265 static uptr kMidMemEnd = 0x4fffffffffULL;
267 extern uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; // Initialized in __asan_init.
270 } // namespace __asan
272 #if SANITIZER_MYRIAD2
273 #include "asan_mapping_myriad.h"
275 #define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) + (SHADOW_OFFSET))
278 #define kLowMemEnd (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0)
280 #define kLowShadowBeg SHADOW_OFFSET
281 #define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd)
283 #define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1)
285 #define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg)
286 #define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd)
288 # define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg)
289 # define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd)
291 // With the zero shadow base we can not actually map pages starting from 0.
292 // This constant is somewhat arbitrary.
293 #define kZeroBaseShadowStart 0
294 #define kZeroBaseMaxShadowStart (1 << 18)
296 #define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 \
297 : kZeroBaseShadowStart)
298 #define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1)
300 #define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0)
301 #define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0)
303 #define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0)
304 #define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0)
308 static inline bool AddrIsInLowMem(uptr a) {
309 PROFILE_ASAN_MAPPING();
310 return a <= kLowMemEnd;
313 static inline bool AddrIsInLowShadow(uptr a) {
314 PROFILE_ASAN_MAPPING();
315 return a >= kLowShadowBeg && a <= kLowShadowEnd;
318 static inline bool AddrIsInMidMem(uptr a) {
319 PROFILE_ASAN_MAPPING();
320 return kMidMemBeg && a >= kMidMemBeg && a <= kMidMemEnd;
323 static inline bool AddrIsInMidShadow(uptr a) {
324 PROFILE_ASAN_MAPPING();
325 return kMidMemBeg && a >= kMidShadowBeg && a <= kMidShadowEnd;
328 static inline bool AddrIsInHighMem(uptr a) {
329 PROFILE_ASAN_MAPPING();
330 return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd;
333 static inline bool AddrIsInHighShadow(uptr a) {
334 PROFILE_ASAN_MAPPING();
335 return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd;
338 static inline bool AddrIsInShadowGap(uptr a) {
339 PROFILE_ASAN_MAPPING();
341 if (a <= kShadowGapEnd)
342 return SHADOW_OFFSET == 0 || a >= kShadowGapBeg;
343 return (a >= kShadowGap2Beg && a <= kShadowGap2End) ||
344 (a >= kShadowGap3Beg && a <= kShadowGap3End);
346 // In zero-based shadow mode we treat addresses near zero as addresses
347 // in shadow gap as well.
348 if (SHADOW_OFFSET == 0)
349 return a <= kShadowGapEnd;
350 return a >= kShadowGapBeg && a <= kShadowGapEnd;
353 } // namespace __asan
355 #endif // SANITIZER_MYRIAD2
359 static inline bool AddrIsInMem(uptr a) {
360 PROFILE_ASAN_MAPPING();
361 return AddrIsInLowMem(a) || AddrIsInMidMem(a) || AddrIsInHighMem(a) ||
362 (flags()->protect_shadow_gap == 0 && AddrIsInShadowGap(a));
365 static inline uptr MemToShadow(uptr p) {
366 PROFILE_ASAN_MAPPING();
367 CHECK(AddrIsInMem(p));
368 return MEM_TO_SHADOW(p);
371 static inline bool AddrIsInShadow(uptr a) {
372 PROFILE_ASAN_MAPPING();
373 return AddrIsInLowShadow(a) || AddrIsInMidShadow(a) || AddrIsInHighShadow(a);
376 static inline bool AddrIsAlignedByGranularity(uptr a) {
377 PROFILE_ASAN_MAPPING();
378 return (a & (SHADOW_GRANULARITY - 1)) == 0;
381 static inline bool AddressIsPoisoned(uptr a) {
382 PROFILE_ASAN_MAPPING();
383 if (SANITIZER_MYRIAD2 && !AddrIsInMem(a) && !AddrIsInShadow(a))
385 const uptr kAccessSize = 1;
386 u8 *shadow_address = (u8*)MEM_TO_SHADOW(a);
387 s8 shadow_value = *shadow_address;
389 u8 last_accessed_byte = (a & (SHADOW_GRANULARITY - 1))
391 return (last_accessed_byte >= shadow_value);
396 // Must be after all calls to PROFILE_ASAN_MAPPING().
397 static const uptr kAsanMappingProfileSize = __LINE__;
399 } // namespace __asan
401 #endif // ASAN_MAPPING_H