1 //===-- msan_allocator.cpp -------------------------- ---------------------===//
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 // This file is a part of MemorySanitizer.
10 //
11 // MemorySanitizer allocator.
12 //===----------------------------------------------------------------------===//
13
14 #include "sanitizer_common/sanitizer_allocator.h"
15 #include "sanitizer_common/sanitizer_allocator_checks.h"
16 #include "sanitizer_common/sanitizer_allocator_interface.h"
17 #include "sanitizer_common/sanitizer_allocator_report.h"
18 #include "sanitizer_common/sanitizer_errno.h"
19 #include "msan.h"
20 #include "msan_allocator.h"
21 #include "msan_origin.h"
22 #include "msan_thread.h"
23 #include "msan_poisoning.h"
24
25 namespace __msan {
26
27 struct Metadata {
28 uptr requested_size;
29 };
30
31 struct MsanMapUnmapCallback {
OnMap__msan::MsanMapUnmapCallback32 void OnMap(uptr p, uptr size) const {}
OnUnmap__msan::MsanMapUnmapCallback33 void OnUnmap(uptr p, uptr size) const {
34 __msan_unpoison((void *)p, size);
35
36 // We are about to unmap a chunk of user memory.
37 // Mark the corresponding shadow memory as not needed.
38 uptr shadow_p = MEM_TO_SHADOW(p);
39 ReleaseMemoryPagesToOS(shadow_p, shadow_p + size);
40 if (__msan_get_track_origins()) {
41 uptr origin_p = MEM_TO_ORIGIN(p);
42 ReleaseMemoryPagesToOS(origin_p, origin_p + size);
43 }
44 }
45 };
46
47 #if defined(__mips64)
48 static const uptr kMaxAllowedMallocSize = 2UL << 30;
49
50 struct AP32 {
51 static const uptr kSpaceBeg = 0;
52 static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
53 static const uptr kMetadataSize = sizeof(Metadata);
54 typedef __sanitizer::CompactSizeClassMap SizeClassMap;
55 static const uptr kRegionSizeLog = 20;
56 using AddressSpaceView = LocalAddressSpaceView;
57 typedef MsanMapUnmapCallback MapUnmapCallback;
58 static const uptr kFlags = 0;
59 };
60 typedef SizeClassAllocator32<AP32> PrimaryAllocator;
61 #elif defined(__x86_64__)
62 #if SANITIZER_NETBSD || \
63 (SANITIZER_LINUX && !defined(MSAN_LINUX_X86_64_OLD_MAPPING))
64 static const uptr kAllocatorSpace = 0x700000000000ULL;
65 #else
66 static const uptr kAllocatorSpace = 0x600000000000ULL;
67 #endif
68 static const uptr kMaxAllowedMallocSize = 8UL << 30;
69
70 struct AP64 { // Allocator64 parameters. Deliberately using a short name.
71 static const uptr kSpaceBeg = kAllocatorSpace;
72 static const uptr kSpaceSize = 0x40000000000; // 4T.
73 static const uptr kMetadataSize = sizeof(Metadata);
74 typedef DefaultSizeClassMap SizeClassMap;
75 typedef MsanMapUnmapCallback MapUnmapCallback;
76 static const uptr kFlags = 0;
77 using AddressSpaceView = LocalAddressSpaceView;
78 };
79
80 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
81
82 #elif defined(__powerpc64__)
83 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
84
85 struct AP64 { // Allocator64 parameters. Deliberately using a short name.
86 static const uptr kSpaceBeg = 0x300000000000;
87 static const uptr kSpaceSize = 0x020000000000; // 2T.
88 static const uptr kMetadataSize = sizeof(Metadata);
89 typedef DefaultSizeClassMap SizeClassMap;
90 typedef MsanMapUnmapCallback MapUnmapCallback;
91 static const uptr kFlags = 0;
92 using AddressSpaceView = LocalAddressSpaceView;
93 };
94
95 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
96 #elif defined(__s390x__)
97 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
98
99 struct AP64 { // Allocator64 parameters. Deliberately using a short name.
100 static const uptr kSpaceBeg = 0x440000000000;
101 static const uptr kSpaceSize = 0x020000000000; // 2T.
102 static const uptr kMetadataSize = sizeof(Metadata);
103 typedef DefaultSizeClassMap SizeClassMap;
104 typedef MsanMapUnmapCallback MapUnmapCallback;
105 static const uptr kFlags = 0;
106 using AddressSpaceView = LocalAddressSpaceView;
107 };
108
109 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
110 #elif defined(__aarch64__)
111 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
112
113 struct AP32 {
114 static const uptr kSpaceBeg = 0;
115 static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
116 static const uptr kMetadataSize = sizeof(Metadata);
117 typedef __sanitizer::CompactSizeClassMap SizeClassMap;
118 static const uptr kRegionSizeLog = 20;
119 using AddressSpaceView = LocalAddressSpaceView;
120 typedef MsanMapUnmapCallback MapUnmapCallback;
121 static const uptr kFlags = 0;
122 };
123 typedef SizeClassAllocator32<AP32> PrimaryAllocator;
124 #endif
125 typedef CombinedAllocator<PrimaryAllocator> Allocator;
126 typedef Allocator::AllocatorCache AllocatorCache;
127
128 static Allocator allocator;
129 static AllocatorCache fallback_allocator_cache;
130 static StaticSpinMutex fallback_mutex;
131
132 static uptr max_malloc_size;
133
MsanAllocatorInit()134 void MsanAllocatorInit() {
135 SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
136 allocator.Init(common_flags()->allocator_release_to_os_interval_ms);
137 if (common_flags()->max_allocation_size_mb)
138 max_malloc_size = Min(common_flags()->max_allocation_size_mb << 20,
139 kMaxAllowedMallocSize);
140 else
141 max_malloc_size = kMaxAllowedMallocSize;
142 }
143
GetAllocatorCache(MsanThreadLocalMallocStorage * ms)144 AllocatorCache *GetAllocatorCache(MsanThreadLocalMallocStorage *ms) {
145 CHECK(ms);
146 CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator_cache));
147 return reinterpret_cast<AllocatorCache *>(ms->allocator_cache);
148 }
149
CommitBack()150 void MsanThreadLocalMallocStorage::CommitBack() {
151 allocator.SwallowCache(GetAllocatorCache(this));
152 }
153
MsanAllocate(StackTrace * stack,uptr size,uptr alignment,bool zeroise)154 static void *MsanAllocate(StackTrace *stack, uptr size, uptr alignment,
155 bool zeroise) {
156 if (size > max_malloc_size) {
157 if (AllocatorMayReturnNull()) {
158 Report("WARNING: MemorySanitizer failed to allocate 0x%zx bytes\n", size);
159 return nullptr;
160 }
161 ReportAllocationSizeTooBig(size, max_malloc_size, stack);
162 }
163 MsanThread *t = GetCurrentThread();
164 void *allocated;
165 if (t) {
166 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
167 allocated = allocator.Allocate(cache, size, alignment);
168 } else {
169 SpinMutexLock l(&fallback_mutex);
170 AllocatorCache *cache = &fallback_allocator_cache;
171 allocated = allocator.Allocate(cache, size, alignment);
172 }
173 if (UNLIKELY(!allocated)) {
174 SetAllocatorOutOfMemory();
175 if (AllocatorMayReturnNull())
176 return nullptr;
177 ReportOutOfMemory(size, stack);
178 }
179 Metadata *meta =
180 reinterpret_cast<Metadata *>(allocator.GetMetaData(allocated));
181 meta->requested_size = size;
182 if (zeroise) {
183 __msan_clear_and_unpoison(allocated, size);
184 } else if (flags()->poison_in_malloc) {
185 __msan_poison(allocated, size);
186 if (__msan_get_track_origins()) {
187 stack->tag = StackTrace::TAG_ALLOC;
188 Origin o = Origin::CreateHeapOrigin(stack);
189 __msan_set_origin(allocated, size, o.raw_id());
190 }
191 }
192 MSAN_MALLOC_HOOK(allocated, size);
193 return allocated;
194 }
195
MsanDeallocate(StackTrace * stack,void * p)196 void MsanDeallocate(StackTrace *stack, void *p) {
197 CHECK(p);
198 MSAN_FREE_HOOK(p);
199 Metadata *meta = reinterpret_cast<Metadata *>(allocator.GetMetaData(p));
200 uptr size = meta->requested_size;
201 meta->requested_size = 0;
202 // This memory will not be reused by anyone else, so we are free to keep it
203 // poisoned.
204 if (flags()->poison_in_free) {
205 __msan_poison(p, size);
206 if (__msan_get_track_origins()) {
207 stack->tag = StackTrace::TAG_DEALLOC;
208 Origin o = Origin::CreateHeapOrigin(stack);
209 __msan_set_origin(p, size, o.raw_id());
210 }
211 }
212 MsanThread *t = GetCurrentThread();
213 if (t) {
214 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
215 allocator.Deallocate(cache, p);
216 } else {
217 SpinMutexLock l(&fallback_mutex);
218 AllocatorCache *cache = &fallback_allocator_cache;
219 allocator.Deallocate(cache, p);
220 }
221 }
222
MsanReallocate(StackTrace * stack,void * old_p,uptr new_size,uptr alignment)223 void *MsanReallocate(StackTrace *stack, void *old_p, uptr new_size,
224 uptr alignment) {
225 Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(old_p));
226 uptr old_size = meta->requested_size;
227 uptr actually_allocated_size = allocator.GetActuallyAllocatedSize(old_p);
228 if (new_size <= actually_allocated_size) {
229 // We are not reallocating here.
230 meta->requested_size = new_size;
231 if (new_size > old_size) {
232 if (flags()->poison_in_malloc) {
233 stack->tag = StackTrace::TAG_ALLOC;
234 PoisonMemory((char *)old_p + old_size, new_size - old_size, stack);
235 }
236 }
237 return old_p;
238 }
239 uptr memcpy_size = Min(new_size, old_size);
240 void *new_p = MsanAllocate(stack, new_size, alignment, false /*zeroise*/);
241 if (new_p) {
242 CopyMemory(new_p, old_p, memcpy_size, stack);
243 MsanDeallocate(stack, old_p);
244 }
245 return new_p;
246 }
247
MsanCalloc(StackTrace * stack,uptr nmemb,uptr size)248 void *MsanCalloc(StackTrace *stack, uptr nmemb, uptr size) {
249 if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
250 if (AllocatorMayReturnNull())
251 return nullptr;
252 ReportCallocOverflow(nmemb, size, stack);
253 }
254 return MsanAllocate(stack, nmemb * size, sizeof(u64), true);
255 }
256
AllocationSize(const void * p)257 static uptr AllocationSize(const void *p) {
258 if (!p) return 0;
259 const void *beg = allocator.GetBlockBegin(p);
260 if (beg != p) return 0;
261 Metadata *b = (Metadata *)allocator.GetMetaData(p);
262 return b->requested_size;
263 }
264
msan_malloc(uptr size,StackTrace * stack)265 void *msan_malloc(uptr size, StackTrace *stack) {
266 return SetErrnoOnNull(MsanAllocate(stack, size, sizeof(u64), false));
267 }
268
msan_calloc(uptr nmemb,uptr size,StackTrace * stack)269 void *msan_calloc(uptr nmemb, uptr size, StackTrace *stack) {
270 return SetErrnoOnNull(MsanCalloc(stack, nmemb, size));
271 }
272
msan_realloc(void * ptr,uptr size,StackTrace * stack)273 void *msan_realloc(void *ptr, uptr size, StackTrace *stack) {
274 if (!ptr)
275 return SetErrnoOnNull(MsanAllocate(stack, size, sizeof(u64), false));
276 if (size == 0) {
277 MsanDeallocate(stack, ptr);
278 return nullptr;
279 }
280 return SetErrnoOnNull(MsanReallocate(stack, ptr, size, sizeof(u64)));
281 }
282
msan_reallocarray(void * ptr,uptr nmemb,uptr size,StackTrace * stack)283 void *msan_reallocarray(void *ptr, uptr nmemb, uptr size, StackTrace *stack) {
284 if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
285 errno = errno_ENOMEM;
286 if (AllocatorMayReturnNull())
287 return nullptr;
288 ReportReallocArrayOverflow(nmemb, size, stack);
289 }
290 return msan_realloc(ptr, nmemb * size, stack);
291 }
292
msan_valloc(uptr size,StackTrace * stack)293 void *msan_valloc(uptr size, StackTrace *stack) {
294 return SetErrnoOnNull(MsanAllocate(stack, size, GetPageSizeCached(), false));
295 }
296
msan_pvalloc(uptr size,StackTrace * stack)297 void *msan_pvalloc(uptr size, StackTrace *stack) {
298 uptr PageSize = GetPageSizeCached();
299 if (UNLIKELY(CheckForPvallocOverflow(size, PageSize))) {
300 errno = errno_ENOMEM;
301 if (AllocatorMayReturnNull())
302 return nullptr;
303 ReportPvallocOverflow(size, stack);
304 }
305 // pvalloc(0) should allocate one page.
306 size = size ? RoundUpTo(size, PageSize) : PageSize;
307 return SetErrnoOnNull(MsanAllocate(stack, size, PageSize, false));
308 }
309
msan_aligned_alloc(uptr alignment,uptr size,StackTrace * stack)310 void *msan_aligned_alloc(uptr alignment, uptr size, StackTrace *stack) {
311 if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(alignment, size))) {
312 errno = errno_EINVAL;
313 if (AllocatorMayReturnNull())
314 return nullptr;
315 ReportInvalidAlignedAllocAlignment(size, alignment, stack);
316 }
317 return SetErrnoOnNull(MsanAllocate(stack, size, alignment, false));
318 }
319
msan_memalign(uptr alignment,uptr size,StackTrace * stack)320 void *msan_memalign(uptr alignment, uptr size, StackTrace *stack) {
321 if (UNLIKELY(!IsPowerOfTwo(alignment))) {
322 errno = errno_EINVAL;
323 if (AllocatorMayReturnNull())
324 return nullptr;
325 ReportInvalidAllocationAlignment(alignment, stack);
326 }
327 return SetErrnoOnNull(MsanAllocate(stack, size, alignment, false));
328 }
329
msan_posix_memalign(void ** memptr,uptr alignment,uptr size,StackTrace * stack)330 int msan_posix_memalign(void **memptr, uptr alignment, uptr size,
331 StackTrace *stack) {
332 if (UNLIKELY(!CheckPosixMemalignAlignment(alignment))) {
333 if (AllocatorMayReturnNull())
334 return errno_EINVAL;
335 ReportInvalidPosixMemalignAlignment(alignment, stack);
336 }
337 void *ptr = MsanAllocate(stack, size, alignment, false);
338 if (UNLIKELY(!ptr))
339 // OOM error is already taken care of by MsanAllocate.
340 return errno_ENOMEM;
341 CHECK(IsAligned((uptr)ptr, alignment));
342 *memptr = ptr;
343 return 0;
344 }
345
346 } // namespace __msan
347
348 using namespace __msan;
349
__sanitizer_get_current_allocated_bytes()350 uptr __sanitizer_get_current_allocated_bytes() {
351 uptr stats[AllocatorStatCount];
352 allocator.GetStats(stats);
353 return stats[AllocatorStatAllocated];
354 }
355
__sanitizer_get_heap_size()356 uptr __sanitizer_get_heap_size() {
357 uptr stats[AllocatorStatCount];
358 allocator.GetStats(stats);
359 return stats[AllocatorStatMapped];
360 }
361
__sanitizer_get_free_bytes()362 uptr __sanitizer_get_free_bytes() { return 1; }
363
__sanitizer_get_unmapped_bytes()364 uptr __sanitizer_get_unmapped_bytes() { return 1; }
365
__sanitizer_get_estimated_allocated_size(uptr size)366 uptr __sanitizer_get_estimated_allocated_size(uptr size) { return size; }
367
__sanitizer_get_ownership(const void * p)368 int __sanitizer_get_ownership(const void *p) { return AllocationSize(p) != 0; }
369
__sanitizer_get_allocated_size(const void * p)370 uptr __sanitizer_get_allocated_size(const void *p) { return AllocationSize(p); }
371