Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 1 | //===-- common.h ------------------------------------------------*- C++ -*-===// |
| 2 | // |
| 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 |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #ifndef SCUDO_COMMON_H_ |
| 10 | #define SCUDO_COMMON_H_ |
| 11 | |
| 12 | #include "internal_defs.h" |
| 13 | |
| 14 | #include "fuchsia.h" |
| 15 | #include "linux.h" |
| 16 | |
| 17 | #include <stddef.h> |
| 18 | #include <string.h> |
| 19 | |
| 20 | namespace scudo { |
| 21 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 22 | template <class Dest, class Source> inline Dest bit_cast(const Source &S) { |
| 23 | static_assert(sizeof(Dest) == sizeof(Source), ""); |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 24 | Dest D; |
| 25 | memcpy(&D, &S, sizeof(D)); |
| 26 | return D; |
| 27 | } |
| 28 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 29 | inline constexpr uptr roundUpTo(uptr X, uptr Boundary) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 30 | return (X + Boundary - 1) & ~(Boundary - 1); |
| 31 | } |
| 32 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 33 | inline constexpr uptr roundDownTo(uptr X, uptr Boundary) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 34 | return X & ~(Boundary - 1); |
| 35 | } |
| 36 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 37 | inline constexpr bool isAligned(uptr X, uptr Alignment) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 38 | return (X & (Alignment - 1)) == 0; |
| 39 | } |
| 40 | |
| 41 | template <class T> constexpr T Min(T A, T B) { return A < B ? A : B; } |
| 42 | |
| 43 | template <class T> constexpr T Max(T A, T B) { return A > B ? A : B; } |
| 44 | |
| 45 | template <class T> void Swap(T &A, T &B) { |
| 46 | T Tmp = A; |
| 47 | A = B; |
| 48 | B = Tmp; |
| 49 | } |
| 50 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 51 | inline bool isPowerOfTwo(uptr X) { return (X & (X - 1)) == 0; } |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 52 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 53 | inline uptr getMostSignificantSetBitIndex(uptr X) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 54 | DCHECK_NE(X, 0U); |
| 55 | return SCUDO_WORDSIZE - 1U - static_cast<uptr>(__builtin_clzl(X)); |
| 56 | } |
| 57 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 58 | inline uptr roundUpToPowerOfTwo(uptr Size) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 59 | DCHECK(Size); |
| 60 | if (isPowerOfTwo(Size)) |
| 61 | return Size; |
| 62 | const uptr Up = getMostSignificantSetBitIndex(Size); |
| 63 | DCHECK_LT(Size, (1UL << (Up + 1))); |
| 64 | DCHECK_GT(Size, (1UL << Up)); |
| 65 | return 1UL << (Up + 1); |
| 66 | } |
| 67 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 68 | inline uptr getLeastSignificantSetBitIndex(uptr X) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 69 | DCHECK_NE(X, 0U); |
| 70 | return static_cast<uptr>(__builtin_ctzl(X)); |
| 71 | } |
| 72 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 73 | inline uptr getLog2(uptr X) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 74 | DCHECK(isPowerOfTwo(X)); |
| 75 | return getLeastSignificantSetBitIndex(X); |
| 76 | } |
| 77 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 78 | inline u32 getRandomU32(u32 *State) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 79 | // ANSI C linear congruential PRNG (16-bit output). |
| 80 | // return (*State = *State * 1103515245 + 12345) >> 16; |
| 81 | // XorShift (32-bit output). |
| 82 | *State ^= *State << 13; |
| 83 | *State ^= *State >> 17; |
| 84 | *State ^= *State << 5; |
| 85 | return *State; |
| 86 | } |
| 87 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 88 | inline u32 getRandomModN(u32 *State, u32 N) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 89 | return getRandomU32(State) % N; // [0, N) |
| 90 | } |
| 91 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 92 | template <typename T> inline void shuffle(T *A, u32 N, u32 *RandState) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 93 | if (N <= 1) |
| 94 | return; |
| 95 | u32 State = *RandState; |
| 96 | for (u32 I = N - 1; I > 0; I--) |
| 97 | Swap(A[I], A[getRandomModN(&State, I + 1)]); |
| 98 | *RandState = State; |
| 99 | } |
| 100 | |
| 101 | // Hardware specific inlinable functions. |
| 102 | |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 103 | inline void yieldProcessor(u8 Count) { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 104 | #if defined(__i386__) || defined(__x86_64__) |
| 105 | __asm__ __volatile__("" ::: "memory"); |
| 106 | for (u8 I = 0; I < Count; I++) |
| 107 | __asm__ __volatile__("pause"); |
| 108 | #elif defined(__aarch64__) || defined(__arm__) |
| 109 | __asm__ __volatile__("" ::: "memory"); |
| 110 | for (u8 I = 0; I < Count; I++) |
| 111 | __asm__ __volatile__("yield"); |
| 112 | #endif |
| 113 | __asm__ __volatile__("" ::: "memory"); |
| 114 | } |
| 115 | |
| 116 | // Platform specific functions. |
| 117 | |
| 118 | extern uptr PageSizeCached; |
| 119 | uptr getPageSizeSlow(); |
Dynamic Tools Team | 09e6d48 | 2019-11-26 18:18:14 -0800 | [diff] [blame] | 120 | inline uptr getPageSizeCached() { |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 121 | // Bionic uses a hardcoded value. |
| 122 | if (SCUDO_ANDROID) |
| 123 | return 4096U; |
| 124 | if (LIKELY(PageSizeCached)) |
| 125 | return PageSizeCached; |
| 126 | return getPageSizeSlow(); |
| 127 | } |
| 128 | |
Dynamic Tools Team | 7fef730 | 2020-01-20 09:50:22 -0800 | [diff] [blame] | 129 | // Returns 0 if the number of CPUs could not be determined. |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 130 | u32 getNumberOfCPUs(); |
| 131 | |
| 132 | const char *getEnv(const char *Name); |
| 133 | |
| 134 | u64 getMonotonicTime(); |
| 135 | |
Dynamic Tools Team | 0d7d2ae | 2020-04-21 15:30:50 -0700 | [diff] [blame] | 136 | u32 getThreadID(); |
| 137 | |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 138 | // Our randomness gathering function is limited to 256 bytes to ensure we get |
| 139 | // as many bytes as requested, and avoid interruptions (on Linux). |
| 140 | constexpr uptr MaxRandomLength = 256U; |
| 141 | bool getRandom(void *Buffer, uptr Length, bool Blocking = false); |
| 142 | |
| 143 | // Platform memory mapping functions. |
| 144 | |
| 145 | #define MAP_ALLOWNOMEM (1U << 0) |
| 146 | #define MAP_NOACCESS (1U << 1) |
| 147 | #define MAP_RESIZABLE (1U << 2) |
Dynamic Tools Team | 48429c7 | 2019-12-04 17:46:15 -0800 | [diff] [blame] | 148 | #define MAP_MEMTAG (1U << 3) |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 149 | |
| 150 | // Our platform memory mapping use is restricted to 3 scenarios: |
| 151 | // - reserve memory at a random address (MAP_NOACCESS); |
| 152 | // - commit memory in a previously reserved space; |
| 153 | // - commit memory at a random address. |
| 154 | // As such, only a subset of parameters combinations is valid, which is checked |
| 155 | // by the function implementation. The Data parameter allows to pass opaque |
| 156 | // platform specific data to the function. |
| 157 | // Returns nullptr on error or dies if MAP_ALLOWNOMEM is not specified. |
| 158 | void *map(void *Addr, uptr Size, const char *Name, uptr Flags = 0, |
| 159 | MapPlatformData *Data = nullptr); |
| 160 | |
| 161 | // Indicates that we are getting rid of the whole mapping, which might have |
| 162 | // further consequences on Data, depending on the platform. |
| 163 | #define UNMAP_ALL (1U << 0) |
| 164 | |
| 165 | void unmap(void *Addr, uptr Size, uptr Flags = 0, |
| 166 | MapPlatformData *Data = nullptr); |
| 167 | |
Peter Collingbourne | cc3d493 | 2020-12-21 18:39:03 -0800 | [diff] [blame] | 168 | void setMemoryPermission(uptr Addr, uptr Size, uptr Flags, |
| 169 | MapPlatformData *Data = nullptr); |
| 170 | |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 171 | void releasePagesToOS(uptr BaseAddress, uptr Offset, uptr Size, |
| 172 | MapPlatformData *Data = nullptr); |
| 173 | |
Kostya Kortchinsky | 4d022f5 | 2021-05-24 09:26:21 -0700 | [diff] [blame^] | 174 | // Internal map & unmap fatal error. This must not call map(). SizeIfOOM shall |
| 175 | // hold the requested size on an out-of-memory error, 0 otherwise. |
| 176 | void NORETURN dieOnMapUnmapError(uptr SizeIfOOM = 0); |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 177 | |
| 178 | // Logging related functions. |
| 179 | |
| 180 | void setAbortMessage(const char *Message); |
| 181 | |
Dynamic Tools Team | 0d7d2ae | 2020-04-21 15:30:50 -0700 | [diff] [blame] | 182 | struct BlockInfo { |
| 183 | uptr BlockBegin; |
| 184 | uptr BlockSize; |
| 185 | uptr RegionBegin; |
| 186 | uptr RegionEnd; |
| 187 | }; |
| 188 | |
Kostya Kortchinsky | c72ca56 | 2020-07-27 09:13:42 -0700 | [diff] [blame] | 189 | enum class Option : u8 { |
| 190 | ReleaseInterval, // Release to OS interval in milliseconds. |
| 191 | MemtagTuning, // Whether to tune tagging for UAF or overflow. |
Peter Collingbourne | 33f8e1a | 2020-09-09 19:15:26 -0700 | [diff] [blame] | 192 | ThreadDisableMemInit, // Whether to disable automatic heap initialization and, |
| 193 | // where possible, memory tagging, on this thread. |
Kostya Kortchinsky | c72ca56 | 2020-07-27 09:13:42 -0700 | [diff] [blame] | 194 | MaxCacheEntriesCount, // Maximum number of blocks that can be cached. |
| 195 | MaxCacheEntrySize, // Maximum size of a block that can be cached. |
| 196 | MaxTSDsCount, // Number of usable TSDs for the shared registry. |
| 197 | }; |
| 198 | |
Dynamic Tools Team | 90d0d18 | 2020-04-29 14:39:23 -0700 | [diff] [blame] | 199 | constexpr unsigned char PatternFillByte = 0xAB; |
| 200 | |
| 201 | enum FillContentsMode { |
| 202 | NoFill = 0, |
| 203 | ZeroFill = 1, |
| 204 | PatternOrZeroFill = 2 // Pattern fill unless the memory is known to be |
| 205 | // zero-initialized already. |
| 206 | }; |
| 207 | |
Dynamic Tools Team | 517193e | 2019-09-11 14:48:41 +0000 | [diff] [blame] | 208 | } // namespace scudo |
| 209 | |
| 210 | #endif // SCUDO_COMMON_H_ |