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 || SANITIZER_LINUX
63 static const uptr kAllocatorSpace = 0x700000000000ULL;
64 #else
65 static const uptr kAllocatorSpace = 0x600000000000ULL;
66 #endif
67 static const uptr kMaxAllowedMallocSize = 8UL << 30;
68
69 struct AP64 { // Allocator64 parameters. Deliberately using a short name.
70 static const uptr kSpaceBeg = kAllocatorSpace;
71 static const uptr kSpaceSize = 0x40000000000; // 4T.
72 static const uptr kMetadataSize = sizeof(Metadata);
73 typedef DefaultSizeClassMap SizeClassMap;
74 typedef MsanMapUnmapCallback MapUnmapCallback;
75 static const uptr kFlags = 0;
76 using AddressSpaceView = LocalAddressSpaceView;
77 };
78
79 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
80
81 #elif defined(__powerpc64__)
82 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
83
84 struct AP64 { // Allocator64 parameters. Deliberately using a short name.
85 static const uptr kSpaceBeg = 0x300000000000;
86 static const uptr kSpaceSize = 0x020000000000; // 2T.
87 static const uptr kMetadataSize = sizeof(Metadata);
88 typedef DefaultSizeClassMap SizeClassMap;
89 typedef MsanMapUnmapCallback MapUnmapCallback;
90 static const uptr kFlags = 0;
91 using AddressSpaceView = LocalAddressSpaceView;
92 };
93
94 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
95 #elif defined(__s390x__)
96 static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
97
98 struct AP64 { // Allocator64 parameters. Deliberately using a short name.
99 static const uptr kSpaceBeg = 0x440000000000;
100 static const uptr kSpaceSize = 0x020000000000; // 2T.
101 static const uptr kMetadataSize = sizeof(Metadata);
102 typedef DefaultSizeClassMap SizeClassMap;
103 typedef MsanMapUnmapCallback MapUnmapCallback;
104 static const uptr kFlags = 0;
105 using AddressSpaceView = LocalAddressSpaceView;
106 };
107
108 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
109 #elif defined(__aarch64__)
110 static const uptr kMaxAllowedMallocSize = 8UL << 30;
111
112 struct AP64 {
113 static const uptr kSpaceBeg = 0xE00000000000ULL;
114 static const uptr kSpaceSize = 0x40000000000; // 4T.
115 static const uptr kMetadataSize = sizeof(Metadata);
116 typedef DefaultSizeClassMap SizeClassMap;
117 typedef MsanMapUnmapCallback MapUnmapCallback;
118 static const uptr kFlags = 0;
119 using AddressSpaceView = LocalAddressSpaceView;
120 };
121 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
122 #endif
123 typedef CombinedAllocator<PrimaryAllocator> Allocator;
124 typedef Allocator::AllocatorCache AllocatorCache;
125
126 static Allocator allocator;
127 static AllocatorCache fallback_allocator_cache;
128 static StaticSpinMutex fallback_mutex;
129
130 static uptr max_malloc_size;
131
MsanAllocatorInit()132 void MsanAllocatorInit() {
133 SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
134 allocator.Init(common_flags()->allocator_release_to_os_interval_ms);
135 if (common_flags()->max_allocation_size_mb)
136 max_malloc_size = Min(common_flags()->max_allocation_size_mb << 20,
137 kMaxAllowedMallocSize);
138 else
139 max_malloc_size = kMaxAllowedMallocSize;
140 }
141
GetAllocatorCache(MsanThreadLocalMallocStorage * ms)142 AllocatorCache *GetAllocatorCache(MsanThreadLocalMallocStorage *ms) {
143 CHECK(ms);
144 CHECK_LE(sizeof(AllocatorCache), sizeof(ms->allocator_cache));
145 return reinterpret_cast<AllocatorCache *>(ms->allocator_cache);
146 }
147
CommitBack()148 void MsanThreadLocalMallocStorage::CommitBack() {
149 allocator.SwallowCache(GetAllocatorCache(this));
150 }
151
MsanAllocate(StackTrace * stack,uptr size,uptr alignment,bool zeroise)152 static void *MsanAllocate(StackTrace *stack, uptr size, uptr alignment,
153 bool zeroise) {
154 if (size > max_malloc_size) {
155 if (AllocatorMayReturnNull()) {
156 Report("WARNING: MemorySanitizer failed to allocate 0x%zx bytes\n", size);
157 return nullptr;
158 }
159 ReportAllocationSizeTooBig(size, max_malloc_size, stack);
160 }
161 if (UNLIKELY(IsRssLimitExceeded())) {
162 if (AllocatorMayReturnNull())
163 return nullptr;
164 ReportRssLimitExceeded(stack);
165 }
166 MsanThread *t = GetCurrentThread();
167 void *allocated;
168 if (t) {
169 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
170 allocated = allocator.Allocate(cache, size, alignment);
171 } else {
172 SpinMutexLock l(&fallback_mutex);
173 AllocatorCache *cache = &fallback_allocator_cache;
174 allocated = allocator.Allocate(cache, size, alignment);
175 }
176 if (UNLIKELY(!allocated)) {
177 SetAllocatorOutOfMemory();
178 if (AllocatorMayReturnNull())
179 return nullptr;
180 ReportOutOfMemory(size, stack);
181 }
182 Metadata *meta =
183 reinterpret_cast<Metadata *>(allocator.GetMetaData(allocated));
184 meta->requested_size = size;
185 if (zeroise) {
186 __msan_clear_and_unpoison(allocated, size);
187 } else if (flags()->poison_in_malloc) {
188 __msan_poison(allocated, size);
189 if (__msan_get_track_origins()) {
190 stack->tag = StackTrace::TAG_ALLOC;
191 Origin o = Origin::CreateHeapOrigin(stack);
192 __msan_set_origin(allocated, size, o.raw_id());
193 }
194 }
195 UnpoisonParam(2);
196 RunMallocHooks(allocated, size);
197 return allocated;
198 }
199
MsanDeallocate(StackTrace * stack,void * p)200 void MsanDeallocate(StackTrace *stack, void *p) {
201 CHECK(p);
202 UnpoisonParam(1);
203 RunFreeHooks(p);
204
205 Metadata *meta = reinterpret_cast<Metadata *>(allocator.GetMetaData(p));
206 uptr size = meta->requested_size;
207 meta->requested_size = 0;
208 // This memory will not be reused by anyone else, so we are free to keep it
209 // poisoned.
210 if (flags()->poison_in_free) {
211 __msan_poison(p, size);
212 if (__msan_get_track_origins()) {
213 stack->tag = StackTrace::TAG_DEALLOC;
214 Origin o = Origin::CreateHeapOrigin(stack);
215 __msan_set_origin(p, size, o.raw_id());
216 }
217 }
218 MsanThread *t = GetCurrentThread();
219 if (t) {
220 AllocatorCache *cache = GetAllocatorCache(&t->malloc_storage());
221 allocator.Deallocate(cache, p);
222 } else {
223 SpinMutexLock l(&fallback_mutex);
224 AllocatorCache *cache = &fallback_allocator_cache;
225 allocator.Deallocate(cache, p);
226 }
227 }
228
MsanReallocate(StackTrace * stack,void * old_p,uptr new_size,uptr alignment)229 static void *MsanReallocate(StackTrace *stack, void *old_p, uptr new_size,
230 uptr alignment) {
231 Metadata *meta = reinterpret_cast<Metadata*>(allocator.GetMetaData(old_p));
232 uptr old_size = meta->requested_size;
233 uptr actually_allocated_size = allocator.GetActuallyAllocatedSize(old_p);
234 if (new_size <= actually_allocated_size) {
235 // We are not reallocating here.
236 meta->requested_size = new_size;
237 if (new_size > old_size) {
238 if (flags()->poison_in_malloc) {
239 stack->tag = StackTrace::TAG_ALLOC;
240 PoisonMemory((char *)old_p + old_size, new_size - old_size, stack);
241 }
242 }
243 return old_p;
244 }
245 uptr memcpy_size = Min(new_size, old_size);
246 void *new_p = MsanAllocate(stack, new_size, alignment, false /*zeroise*/);
247 if (new_p) {
248 CopyMemory(new_p, old_p, memcpy_size, stack);
249 MsanDeallocate(stack, old_p);
250 }
251 return new_p;
252 }
253
MsanCalloc(StackTrace * stack,uptr nmemb,uptr size)254 static void *MsanCalloc(StackTrace *stack, uptr nmemb, uptr size) {
255 if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
256 if (AllocatorMayReturnNull())
257 return nullptr;
258 ReportCallocOverflow(nmemb, size, stack);
259 }
260 return MsanAllocate(stack, nmemb * size, sizeof(u64), true);
261 }
262
AllocationSize(const void * p)263 static uptr AllocationSize(const void *p) {
264 if (!p) return 0;
265 const void *beg = allocator.GetBlockBegin(p);
266 if (beg != p) return 0;
267 Metadata *b = (Metadata *)allocator.GetMetaData(p);
268 return b->requested_size;
269 }
270
msan_malloc(uptr size,StackTrace * stack)271 void *msan_malloc(uptr size, StackTrace *stack) {
272 return SetErrnoOnNull(MsanAllocate(stack, size, sizeof(u64), false));
273 }
274
msan_calloc(uptr nmemb,uptr size,StackTrace * stack)275 void *msan_calloc(uptr nmemb, uptr size, StackTrace *stack) {
276 return SetErrnoOnNull(MsanCalloc(stack, nmemb, size));
277 }
278
msan_realloc(void * ptr,uptr size,StackTrace * stack)279 void *msan_realloc(void *ptr, uptr size, StackTrace *stack) {
280 if (!ptr)
281 return SetErrnoOnNull(MsanAllocate(stack, size, sizeof(u64), false));
282 if (size == 0) {
283 MsanDeallocate(stack, ptr);
284 return nullptr;
285 }
286 return SetErrnoOnNull(MsanReallocate(stack, ptr, size, sizeof(u64)));
287 }
288
msan_reallocarray(void * ptr,uptr nmemb,uptr size,StackTrace * stack)289 void *msan_reallocarray(void *ptr, uptr nmemb, uptr size, StackTrace *stack) {
290 if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
291 errno = errno_ENOMEM;
292 if (AllocatorMayReturnNull())
293 return nullptr;
294 ReportReallocArrayOverflow(nmemb, size, stack);
295 }
296 return msan_realloc(ptr, nmemb * size, stack);
297 }
298
msan_valloc(uptr size,StackTrace * stack)299 void *msan_valloc(uptr size, StackTrace *stack) {
300 return SetErrnoOnNull(MsanAllocate(stack, size, GetPageSizeCached(), false));
301 }
302
msan_pvalloc(uptr size,StackTrace * stack)303 void *msan_pvalloc(uptr size, StackTrace *stack) {
304 uptr PageSize = GetPageSizeCached();
305 if (UNLIKELY(CheckForPvallocOverflow(size, PageSize))) {
306 errno = errno_ENOMEM;
307 if (AllocatorMayReturnNull())
308 return nullptr;
309 ReportPvallocOverflow(size, stack);
310 }
311 // pvalloc(0) should allocate one page.
312 size = size ? RoundUpTo(size, PageSize) : PageSize;
313 return SetErrnoOnNull(MsanAllocate(stack, size, PageSize, false));
314 }
315
msan_aligned_alloc(uptr alignment,uptr size,StackTrace * stack)316 void *msan_aligned_alloc(uptr alignment, uptr size, StackTrace *stack) {
317 if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(alignment, size))) {
318 errno = errno_EINVAL;
319 if (AllocatorMayReturnNull())
320 return nullptr;
321 ReportInvalidAlignedAllocAlignment(size, alignment, stack);
322 }
323 return SetErrnoOnNull(MsanAllocate(stack, size, alignment, false));
324 }
325
msan_memalign(uptr alignment,uptr size,StackTrace * stack)326 void *msan_memalign(uptr alignment, uptr size, StackTrace *stack) {
327 if (UNLIKELY(!IsPowerOfTwo(alignment))) {
328 errno = errno_EINVAL;
329 if (AllocatorMayReturnNull())
330 return nullptr;
331 ReportInvalidAllocationAlignment(alignment, stack);
332 }
333 return SetErrnoOnNull(MsanAllocate(stack, size, alignment, false));
334 }
335
msan_posix_memalign(void ** memptr,uptr alignment,uptr size,StackTrace * stack)336 int msan_posix_memalign(void **memptr, uptr alignment, uptr size,
337 StackTrace *stack) {
338 if (UNLIKELY(!CheckPosixMemalignAlignment(alignment))) {
339 if (AllocatorMayReturnNull())
340 return errno_EINVAL;
341 ReportInvalidPosixMemalignAlignment(alignment, stack);
342 }
343 void *ptr = MsanAllocate(stack, size, alignment, false);
344 if (UNLIKELY(!ptr))
345 // OOM error is already taken care of by MsanAllocate.
346 return errno_ENOMEM;
347 CHECK(IsAligned((uptr)ptr, alignment));
348 *memptr = ptr;
349 return 0;
350 }
351
352 } // namespace __msan
353
354 using namespace __msan;
355
__sanitizer_get_current_allocated_bytes()356 uptr __sanitizer_get_current_allocated_bytes() {
357 uptr stats[AllocatorStatCount];
358 allocator.GetStats(stats);
359 return stats[AllocatorStatAllocated];
360 }
361
__sanitizer_get_heap_size()362 uptr __sanitizer_get_heap_size() {
363 uptr stats[AllocatorStatCount];
364 allocator.GetStats(stats);
365 return stats[AllocatorStatMapped];
366 }
367
__sanitizer_get_free_bytes()368 uptr __sanitizer_get_free_bytes() { return 1; }
369
__sanitizer_get_unmapped_bytes()370 uptr __sanitizer_get_unmapped_bytes() { return 1; }
371
__sanitizer_get_estimated_allocated_size(uptr size)372 uptr __sanitizer_get_estimated_allocated_size(uptr size) { return size; }
373
__sanitizer_get_ownership(const void * p)374 int __sanitizer_get_ownership(const void *p) { return AllocationSize(p) != 0; }
375
__sanitizer_get_allocated_size(const void * p)376 uptr __sanitizer_get_allocated_size(const void *p) { return AllocationSize(p); }
377