1 //===-- asan_mapping.h ------------------------------------------*- C++ -*-===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file is a part of AddressSanitizer, an address sanity checker.
11 // Defines ASan memory mapping.
12 //===----------------------------------------------------------------------===//
13 #ifndef ASAN_MAPPING_H
14 #define ASAN_MAPPING_H
16 #include "asan_internal.h"
18 // The full explanation of the memory mapping could be found here:
19 // https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm
21 // Typical shadow mapping on Linux/x86_64 with SHADOW_OFFSET == 0x00007fff8000:
22 // || `[0x10007fff8000, 0x7fffffffffff]` || HighMem ||
23 // || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow ||
24 // || `[0x00008fff7000, 0x02008fff6fff]` || ShadowGap ||
25 // || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow ||
26 // || `[0x000000000000, 0x00007fff7fff]` || LowMem ||
28 // When SHADOW_OFFSET is zero (-pie):
29 // || `[0x100000000000, 0x7fffffffffff]` || HighMem ||
30 // || `[0x020000000000, 0x0fffffffffff]` || HighShadow ||
31 // || `[0x000000040000, 0x01ffffffffff]` || ShadowGap ||
33 // Special case when something is already mapped between
34 // 0x003000000000 and 0x005000000000 (e.g. when prelink is installed):
35 // || `[0x10007fff8000, 0x7fffffffffff]` || HighMem ||
36 // || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow ||
37 // || `[0x005000000000, 0x02008fff6fff]` || ShadowGap3 ||
38 // || `[0x003000000000, 0x004fffffffff]` || MidMem ||
39 // || `[0x000a7fff8000, 0x002fffffffff]` || ShadowGap2 ||
40 // || `[0x00067fff8000, 0x000a7fff7fff]` || MidShadow ||
41 // || `[0x00008fff7000, 0x00067fff7fff]` || ShadowGap ||
42 // || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow ||
43 // || `[0x000000000000, 0x00007fff7fff]` || LowMem ||
45 // Default Linux/i386 mapping on x86_64 machine:
46 // || `[0x40000000, 0xffffffff]` || HighMem ||
47 // || `[0x28000000, 0x3fffffff]` || HighShadow ||
48 // || `[0x24000000, 0x27ffffff]` || ShadowGap ||
49 // || `[0x20000000, 0x23ffffff]` || LowShadow ||
50 // || `[0x00000000, 0x1fffffff]` || LowMem ||
52 // Default Linux/i386 mapping on i386 machine
53 // (addresses starting with 0xc0000000 are reserved
54 // for kernel and thus not sanitized):
55 // || `[0x38000000, 0xbfffffff]` || HighMem ||
56 // || `[0x27000000, 0x37ffffff]` || HighShadow ||
57 // || `[0x24000000, 0x26ffffff]` || ShadowGap ||
58 // || `[0x20000000, 0x23ffffff]` || LowShadow ||
59 // || `[0x00000000, 0x1fffffff]` || LowMem ||
61 // Default Linux/MIPS32 mapping:
62 // || `[0x2aaa0000, 0xffffffff]` || HighMem ||
63 // || `[0x0fff4000, 0x2aa9ffff]` || HighShadow ||
64 // || `[0x0bff4000, 0x0fff3fff]` || ShadowGap ||
65 // || `[0x0aaa0000, 0x0bff3fff]` || LowShadow ||
66 // || `[0x00000000, 0x0aa9ffff]` || LowMem ||
68 // Default Linux/MIPS64 mapping:
69 // || `[0x4000000000, 0xffffffffff]` || HighMem ||
70 // || `[0x2800000000, 0x3fffffffff]` || HighShadow ||
71 // || `[0x2400000000, 0x27ffffffff]` || ShadowGap ||
72 // || `[0x2000000000, 0x23ffffffff]` || LowShadow ||
73 // || `[0x0000000000, 0x1fffffffff]` || LowMem ||
75 // Default Linux/AArch64 (39-bit VMA) mapping:
76 // || `[0x2000000000, 0x7fffffffff]` || highmem ||
77 // || `[0x1400000000, 0x1fffffffff]` || highshadow ||
78 // || `[0x1200000000, 0x13ffffffff]` || shadowgap ||
79 // || `[0x1000000000, 0x11ffffffff]` || lowshadow ||
80 // || `[0x0000000000, 0x0fffffffff]` || lowmem ||
82 // RISC-V has only 38 bits for task size
83 // Low mem size is set with kRiscv64_ShadowOffset64 in
84 // compiler-rt/lib/asan/asan_allocator.h and in
85 // llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp with
86 // kRiscv64_ShadowOffset64, High mem top border is set with
87 // GetMaxVirtualAddress() in
88 // compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
89 // Default Linux/RISCV64 Sv39/Sv48 mapping:
90 // || `[0x000820000000, 0x003fffffffff]` || HighMem ||
91 // || `[0x000124000000, 0x00081fffffff]` || HighShadow ||
92 // || `[0x000024000000, 0x000123ffffff]` || ShadowGap ||
93 // || `[0x000020000000, 0x000023ffffff]` || LowShadow ||
94 // || `[0x000000000000, 0x00001fffffff]` || LowMem ||
96 // Default Linux/AArch64 (42-bit VMA) mapping:
97 // || `[0x10000000000, 0x3ffffffffff]` || highmem ||
98 // || `[0x0a000000000, 0x0ffffffffff]` || highshadow ||
99 // || `[0x09000000000, 0x09fffffffff]` || shadowgap ||
100 // || `[0x08000000000, 0x08fffffffff]` || lowshadow ||
101 // || `[0x00000000000, 0x07fffffffff]` || lowmem ||
103 // Default Linux/S390 mapping:
104 // || `[0x30000000, 0x7fffffff]` || HighMem ||
105 // || `[0x26000000, 0x2fffffff]` || HighShadow ||
106 // || `[0x24000000, 0x25ffffff]` || ShadowGap ||
107 // || `[0x20000000, 0x23ffffff]` || LowShadow ||
108 // || `[0x00000000, 0x1fffffff]` || LowMem ||
110 // Default Linux/SystemZ mapping:
111 // || `[0x14000000000000, 0x1fffffffffffff]` || HighMem ||
112 // || `[0x12800000000000, 0x13ffffffffffff]` || HighShadow ||
113 // || `[0x12000000000000, 0x127fffffffffff]` || ShadowGap ||
114 // || `[0x10000000000000, 0x11ffffffffffff]` || LowShadow ||
115 // || `[0x00000000000000, 0x0fffffffffffff]` || LowMem ||
117 // Default Linux/SPARC64 (52-bit VMA) mapping:
118 // || `[0x8000000000000, 0xfffffffffffff]` || HighMem ||
119 // || `[0x1080000000000, 0x207ffffffffff]` || HighShadow ||
120 // || `[0x0090000000000, 0x107ffffffffff]` || ShadowGap ||
121 // || `[0x0080000000000, 0x008ffffffffff]` || LowShadow ||
122 // || `[0x0000000000000, 0x007ffffffffff]` || LowMem ||
124 // Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:
125 // || `[0x500000000000, 0x7fffffffffff]` || HighMem ||
126 // || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow ||
127 // || `[0x480000000000, 0x49ffffffffff]` || ShadowGap ||
128 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||
129 // || `[0x000000000000, 0x3fffffffffff]` || LowMem ||
131 // Shadow mapping on FreeBSD/i386 with SHADOW_OFFSET == 0x40000000:
132 // || `[0x60000000, 0xffffffff]` || HighMem ||
133 // || `[0x4c000000, 0x5fffffff]` || HighShadow ||
134 // || `[0x48000000, 0x4bffffff]` || ShadowGap ||
135 // || `[0x40000000, 0x47ffffff]` || LowShadow ||
136 // || `[0x00000000, 0x3fffffff]` || LowMem ||
138 // Shadow mapping on NetBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:
139 // || `[0x4feffffffe01, 0x7f7ffffff000]` || HighMem ||
140 // || `[0x49fdffffffc0, 0x4feffffffe00]` || HighShadow ||
141 // || `[0x480000000000, 0x49fdffffffbf]` || ShadowGap ||
142 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||
143 // || `[0x000000000000, 0x3fffffffffff]` || LowMem ||
145 // Shadow mapping on NetBSD/i386 with SHADOW_OFFSET == 0x40000000:
146 // || `[0x60000000, 0xfffff000]` || HighMem ||
147 // || `[0x4c000000, 0x5fffffff]` || HighShadow ||
148 // || `[0x48000000, 0x4bffffff]` || ShadowGap ||
149 // || `[0x40000000, 0x47ffffff]` || LowShadow ||
150 // || `[0x00000000, 0x3fffffff]` || LowMem ||
152 // Default Windows/i386 mapping:
153 // (the exact location of HighShadow/HighMem may vary depending
154 // on WoW64, /LARGEADDRESSAWARE, etc).
155 // || `[0x50000000, 0xffffffff]` || HighMem ||
156 // || `[0x3a000000, 0x4fffffff]` || HighShadow ||
157 // || `[0x36000000, 0x39ffffff]` || ShadowGap ||
158 // || `[0x30000000, 0x35ffffff]` || LowShadow ||
159 // || `[0x00000000, 0x2fffffff]` || LowMem ||
161 // Shadow mapping on Myriad2 (for shadow scale 5):
162 // || `[0x9ff80000, 0x9fffffff]` || ShadowGap ||
163 // || `[0x9f000000, 0x9ff7ffff]` || LowShadow ||
164 // || `[0x80000000, 0x9effffff]` || LowMem ||
165 // || `[0x00000000, 0x7fffffff]` || Ignored ||
167 #if defined(ASAN_SHADOW_SCALE)
168 static const u64 kDefaultShadowScale
= ASAN_SHADOW_SCALE
;
170 static const u64 kDefaultShadowScale
= SANITIZER_MYRIAD2
? 5 : 3;
172 static const u64 kDefaultShadowSentinel
= ~(uptr
)0;
173 static const u64 kDefaultShadowOffset32
= 1ULL << 29; // 0x20000000
174 static const u64 kDefaultShadowOffset64
= 1ULL << 44;
175 static const u64 kDefaultShort64bitShadowOffset
=
176 0x7FFFFFFF & (~0xFFFULL
<< kDefaultShadowScale
); // < 2G.
177 static const u64 kAArch64_ShadowOffset64
= 1ULL << 36;
178 static const u64 kRiscv64_ShadowOffset64
= 0x20000000;
179 static const u64 kMIPS32_ShadowOffset32
= 0x0aaa0000;
180 static const u64 kMIPS64_ShadowOffset64
= 1ULL << 37;
181 static const u64 kPPC64_ShadowOffset64
= 1ULL << 41;
182 static const u64 kSystemZ_ShadowOffset64
= 1ULL << 52;
183 static const u64 kSPARC64_ShadowOffset64
= 1ULL << 43; // 0x80000000000
184 static const u64 kFreeBSD_ShadowOffset32
= 1ULL << 30; // 0x40000000
185 static const u64 kFreeBSD_ShadowOffset64
= 1ULL << 46; // 0x400000000000
186 static const u64 kNetBSD_ShadowOffset32
= 1ULL << 30; // 0x40000000
187 static const u64 kNetBSD_ShadowOffset64
= 1ULL << 46; // 0x400000000000
188 static const u64 kWindowsShadowOffset32
= 3ULL << 28; // 0x30000000
190 static const u64 kMyriadMemoryOffset32
= 0x80000000ULL
;
191 static const u64 kMyriadMemorySize32
= 0x20000000ULL
;
192 static const u64 kMyriadMemoryEnd32
=
193 kMyriadMemoryOffset32
+ kMyriadMemorySize32
- 1;
194 static const u64 kMyriadShadowOffset32
=
195 (kMyriadMemoryOffset32
+ kMyriadMemorySize32
-
196 (kMyriadMemorySize32
>> kDefaultShadowScale
));
197 static const u64 kMyriadCacheBitMask32
= 0x40000000ULL
;
199 #define SHADOW_SCALE kDefaultShadowScale
201 #if SANITIZER_FUCHSIA
202 # define SHADOW_OFFSET (0)
203 #elif SANITIZER_WORDSIZE == 32
204 # if SANITIZER_ANDROID
205 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
206 # elif defined(__mips__)
207 # define SHADOW_OFFSET kMIPS32_ShadowOffset32
208 # elif SANITIZER_FREEBSD
209 # define SHADOW_OFFSET kFreeBSD_ShadowOffset32
210 # elif SANITIZER_NETBSD
211 # define SHADOW_OFFSET kNetBSD_ShadowOffset32
212 # elif SANITIZER_WINDOWS
213 # define SHADOW_OFFSET kWindowsShadowOffset32
215 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
216 # elif SANITIZER_MYRIAD2
217 # define SHADOW_OFFSET kMyriadShadowOffset32
219 # define SHADOW_OFFSET kDefaultShadowOffset32
223 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
224 # elif SANITIZER_MAC && defined(__aarch64__)
225 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
226 #elif SANITIZER_RISCV64
227 #define SHADOW_OFFSET kRiscv64_ShadowOffset64
228 # elif defined(__aarch64__)
229 # define SHADOW_OFFSET kAArch64_ShadowOffset64
230 # elif defined(__powerpc64__)
231 # define SHADOW_OFFSET kPPC64_ShadowOffset64
232 # elif defined(__s390x__)
233 # define SHADOW_OFFSET kSystemZ_ShadowOffset64
234 # elif SANITIZER_FREEBSD
235 # define SHADOW_OFFSET kFreeBSD_ShadowOffset64
236 # elif SANITIZER_NETBSD
237 # define SHADOW_OFFSET kNetBSD_ShadowOffset64
239 # define SHADOW_OFFSET kDefaultShadowOffset64
240 # elif defined(__mips64)
241 # define SHADOW_OFFSET kMIPS64_ShadowOffset64
242 #elif defined(__sparc__)
243 #define SHADOW_OFFSET kSPARC64_ShadowOffset64
244 # elif SANITIZER_WINDOWS64
245 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
247 # define SHADOW_OFFSET kDefaultShort64bitShadowOffset
251 #if SANITIZER_ANDROID && defined(__arm__)
252 # define ASAN_PREMAP_SHADOW 1
254 # define ASAN_PREMAP_SHADOW 0
257 #define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE)
259 #define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below.
261 #if DO_ASAN_MAPPING_PROFILE
262 # define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++;
264 # define PROFILE_ASAN_MAPPING()
267 // If 1, all shadow boundaries are constants.
268 // Don't set to 1 other than for testing.
269 #define ASAN_FIXED_MAPPING 0
273 extern uptr AsanMappingProfile
[];
275 #if ASAN_FIXED_MAPPING
276 // Fixed mapping for 64-bit Linux. Mostly used for performance comparison
277 // with non-fixed mapping. As of r175253 (Feb 2013) the performance
278 // difference between fixed and non-fixed mapping is below the noise level.
279 static uptr kHighMemEnd
= 0x7fffffffffffULL
;
280 static uptr kMidMemBeg
= 0x3000000000ULL
;
281 static uptr kMidMemEnd
= 0x4fffffffffULL
;
283 extern uptr kHighMemEnd
, kMidMemBeg
, kMidMemEnd
; // Initialized in __asan_init.
286 } // namespace __asan
288 #if SANITIZER_MYRIAD2
289 #include "asan_mapping_myriad.h"
290 #elif defined(__sparc__) && SANITIZER_WORDSIZE == 64
291 #include "asan_mapping_sparc64.h"
293 #define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) + (SHADOW_OFFSET))
296 #define kLowMemEnd (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0)
298 #define kLowShadowBeg SHADOW_OFFSET
299 #define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd)
301 #define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1)
303 #define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg)
304 #define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd)
306 # define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg)
307 # define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd)
309 // With the zero shadow base we can not actually map pages starting from 0.
310 // This constant is somewhat arbitrary.
311 #define kZeroBaseShadowStart 0
312 #define kZeroBaseMaxShadowStart (1 << 18)
314 #define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 \
315 : kZeroBaseShadowStart)
316 #define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1)
318 #define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0)
319 #define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0)
321 #define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0)
322 #define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0)
326 static inline bool AddrIsInLowMem(uptr a
) {
327 PROFILE_ASAN_MAPPING();
328 return a
<= kLowMemEnd
;
331 static inline bool AddrIsInLowShadow(uptr a
) {
332 PROFILE_ASAN_MAPPING();
333 return a
>= kLowShadowBeg
&& a
<= kLowShadowEnd
;
336 static inline bool AddrIsInMidMem(uptr a
) {
337 PROFILE_ASAN_MAPPING();
338 return kMidMemBeg
&& a
>= kMidMemBeg
&& a
<= kMidMemEnd
;
341 static inline bool AddrIsInMidShadow(uptr a
) {
342 PROFILE_ASAN_MAPPING();
343 return kMidMemBeg
&& a
>= kMidShadowBeg
&& a
<= kMidShadowEnd
;
346 static inline bool AddrIsInHighMem(uptr a
) {
347 PROFILE_ASAN_MAPPING();
348 return kHighMemBeg
&& a
>= kHighMemBeg
&& a
<= kHighMemEnd
;
351 static inline bool AddrIsInHighShadow(uptr a
) {
352 PROFILE_ASAN_MAPPING();
353 return kHighMemBeg
&& a
>= kHighShadowBeg
&& a
<= kHighShadowEnd
;
356 static inline bool AddrIsInShadowGap(uptr a
) {
357 PROFILE_ASAN_MAPPING();
359 if (a
<= kShadowGapEnd
)
360 return SHADOW_OFFSET
== 0 || a
>= kShadowGapBeg
;
361 return (a
>= kShadowGap2Beg
&& a
<= kShadowGap2End
) ||
362 (a
>= kShadowGap3Beg
&& a
<= kShadowGap3End
);
364 // In zero-based shadow mode we treat addresses near zero as addresses
365 // in shadow gap as well.
366 if (SHADOW_OFFSET
== 0)
367 return a
<= kShadowGapEnd
;
368 return a
>= kShadowGapBeg
&& a
<= kShadowGapEnd
;
371 } // namespace __asan
373 #endif // SANITIZER_MYRIAD2
377 static inline uptr
MemToShadowSize(uptr size
) { return size
>> SHADOW_SCALE
; }
379 static inline bool AddrIsInMem(uptr a
) {
380 PROFILE_ASAN_MAPPING();
381 return AddrIsInLowMem(a
) || AddrIsInMidMem(a
) || AddrIsInHighMem(a
) ||
382 (flags()->protect_shadow_gap
== 0 && AddrIsInShadowGap(a
));
385 static inline uptr
MemToShadow(uptr p
) {
386 PROFILE_ASAN_MAPPING();
387 CHECK(AddrIsInMem(p
));
388 return MEM_TO_SHADOW(p
);
391 static inline bool AddrIsInShadow(uptr a
) {
392 PROFILE_ASAN_MAPPING();
393 return AddrIsInLowShadow(a
) || AddrIsInMidShadow(a
) || AddrIsInHighShadow(a
);
396 static inline bool AddrIsAlignedByGranularity(uptr a
) {
397 PROFILE_ASAN_MAPPING();
398 return (a
& (SHADOW_GRANULARITY
- 1)) == 0;
401 static inline bool AddressIsPoisoned(uptr a
) {
402 PROFILE_ASAN_MAPPING();
403 if (SANITIZER_MYRIAD2
&& !AddrIsInMem(a
) && !AddrIsInShadow(a
))
405 const uptr kAccessSize
= 1;
406 u8
*shadow_address
= (u8
*)MEM_TO_SHADOW(a
);
407 s8 shadow_value
= *shadow_address
;
409 u8 last_accessed_byte
= (a
& (SHADOW_GRANULARITY
- 1))
411 return (last_accessed_byte
>= shadow_value
);
416 // Must be after all calls to PROFILE_ASAN_MAPPING().
417 static const uptr kAsanMappingProfileSize
= __LINE__
;
419 } // namespace __asan
421 #endif // ASAN_MAPPING_H