1 //=-- lsan_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 LeakSanitizer.
10 // See lsan_allocator.h for details.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "lsan_allocator.h"
15
16 #include "sanitizer_common/sanitizer_allocator.h"
17 #include "sanitizer_common/sanitizer_allocator_checks.h"
18 #include "sanitizer_common/sanitizer_allocator_interface.h"
19 #include "sanitizer_common/sanitizer_allocator_report.h"
20 #include "sanitizer_common/sanitizer_errno.h"
21 #include "sanitizer_common/sanitizer_internal_defs.h"
22 #include "sanitizer_common/sanitizer_stackdepot.h"
23 #include "sanitizer_common/sanitizer_stacktrace.h"
24 #include "lsan_common.h"
25
26 extern "C" void *memset(void *ptr, int value, uptr num);
27
28 namespace __lsan {
29 #if defined(__i386__) || defined(__arm__)
30 static const uptr kMaxAllowedMallocSize = 1UL << 30;
31 #elif defined(__mips64) || defined(__aarch64__)
32 static const uptr kMaxAllowedMallocSize = 4UL << 30;
33 #else
34 static const uptr kMaxAllowedMallocSize = 8UL << 30;
35 #endif
36
37 static Allocator allocator;
38
39 static uptr max_malloc_size;
40
InitializeAllocator()41 void InitializeAllocator() {
42 SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
43 allocator.InitLinkerInitialized(
44 common_flags()->allocator_release_to_os_interval_ms);
45 if (common_flags()->max_allocation_size_mb)
46 max_malloc_size = Min(common_flags()->max_allocation_size_mb << 20,
47 kMaxAllowedMallocSize);
48 else
49 max_malloc_size = kMaxAllowedMallocSize;
50 }
51
AllocatorThreadFinish()52 void AllocatorThreadFinish() {
53 allocator.SwallowCache(GetAllocatorCache());
54 }
55
Metadata(const void * p)56 static ChunkMetadata *Metadata(const void *p) {
57 return reinterpret_cast<ChunkMetadata *>(allocator.GetMetaData(p));
58 }
59
RegisterAllocation(const StackTrace & stack,void * p,uptr size)60 static void RegisterAllocation(const StackTrace &stack, void *p, uptr size) {
61 if (!p) return;
62 ChunkMetadata *m = Metadata(p);
63 CHECK(m);
64 m->tag = DisabledInThisThread() ? kIgnored : kDirectlyLeaked;
65 m->stack_trace_id = StackDepotPut(stack);
66 m->requested_size = size;
67 atomic_store(reinterpret_cast<atomic_uint8_t *>(m), 1, memory_order_relaxed);
68 }
69
RegisterDeallocation(void * p)70 static void RegisterDeallocation(void *p) {
71 if (!p) return;
72 ChunkMetadata *m = Metadata(p);
73 CHECK(m);
74 atomic_store(reinterpret_cast<atomic_uint8_t *>(m), 0, memory_order_relaxed);
75 }
76
ReportAllocationSizeTooBig(uptr size,const StackTrace & stack)77 static void *ReportAllocationSizeTooBig(uptr size, const StackTrace &stack) {
78 if (AllocatorMayReturnNull()) {
79 Report("WARNING: LeakSanitizer failed to allocate 0x%zx bytes\n", size);
80 return nullptr;
81 }
82 ReportAllocationSizeTooBig(size, max_malloc_size, &stack);
83 }
84
Allocate(const StackTrace & stack,uptr size,uptr alignment,bool cleared)85 void *Allocate(const StackTrace &stack, uptr size, uptr alignment,
86 bool cleared) {
87 if (size == 0)
88 size = 1;
89 if (size > max_malloc_size)
90 return ReportAllocationSizeTooBig(size, stack);
91 void *p = allocator.Allocate(GetAllocatorCache(), size, alignment);
92 if (UNLIKELY(!p)) {
93 SetAllocatorOutOfMemory();
94 if (AllocatorMayReturnNull())
95 return nullptr;
96 ReportOutOfMemory(size, &stack);
97 }
98 // Do not rely on the allocator to clear the memory (it's slow).
99 if (cleared && allocator.FromPrimary(p))
100 memset(p, 0, size);
101 RegisterAllocation(stack, p, size);
102 if (&__sanitizer_malloc_hook) __sanitizer_malloc_hook(p, size);
103 RunMallocHooks(p, size);
104 return p;
105 }
106
Calloc(uptr nmemb,uptr size,const StackTrace & stack)107 static void *Calloc(uptr nmemb, uptr size, const StackTrace &stack) {
108 if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
109 if (AllocatorMayReturnNull())
110 return nullptr;
111 ReportCallocOverflow(nmemb, size, &stack);
112 }
113 size *= nmemb;
114 return Allocate(stack, size, 1, true);
115 }
116
Deallocate(void * p)117 void Deallocate(void *p) {
118 if (&__sanitizer_free_hook) __sanitizer_free_hook(p);
119 RunFreeHooks(p);
120 RegisterDeallocation(p);
121 allocator.Deallocate(GetAllocatorCache(), p);
122 }
123
Reallocate(const StackTrace & stack,void * p,uptr new_size,uptr alignment)124 void *Reallocate(const StackTrace &stack, void *p, uptr new_size,
125 uptr alignment) {
126 RegisterDeallocation(p);
127 if (new_size > max_malloc_size) {
128 allocator.Deallocate(GetAllocatorCache(), p);
129 return ReportAllocationSizeTooBig(new_size, stack);
130 }
131 p = allocator.Reallocate(GetAllocatorCache(), p, new_size, alignment);
132 RegisterAllocation(stack, p, new_size);
133 return p;
134 }
135
GetAllocatorCacheRange(uptr * begin,uptr * end)136 void GetAllocatorCacheRange(uptr *begin, uptr *end) {
137 *begin = (uptr)GetAllocatorCache();
138 *end = *begin + sizeof(AllocatorCache);
139 }
140
GetMallocUsableSize(const void * p)141 uptr GetMallocUsableSize(const void *p) {
142 ChunkMetadata *m = Metadata(p);
143 if (!m) return 0;
144 return m->requested_size;
145 }
146
lsan_posix_memalign(void ** memptr,uptr alignment,uptr size,const StackTrace & stack)147 int lsan_posix_memalign(void **memptr, uptr alignment, uptr size,
148 const StackTrace &stack) {
149 if (UNLIKELY(!CheckPosixMemalignAlignment(alignment))) {
150 if (AllocatorMayReturnNull())
151 return errno_EINVAL;
152 ReportInvalidPosixMemalignAlignment(alignment, &stack);
153 }
154 void *ptr = Allocate(stack, size, alignment, kAlwaysClearMemory);
155 if (UNLIKELY(!ptr))
156 // OOM error is already taken care of by Allocate.
157 return errno_ENOMEM;
158 CHECK(IsAligned((uptr)ptr, alignment));
159 *memptr = ptr;
160 return 0;
161 }
162
lsan_aligned_alloc(uptr alignment,uptr size,const StackTrace & stack)163 void *lsan_aligned_alloc(uptr alignment, uptr size, const StackTrace &stack) {
164 if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(alignment, size))) {
165 errno = errno_EINVAL;
166 if (AllocatorMayReturnNull())
167 return nullptr;
168 ReportInvalidAlignedAllocAlignment(size, alignment, &stack);
169 }
170 return SetErrnoOnNull(Allocate(stack, size, alignment, kAlwaysClearMemory));
171 }
172
lsan_memalign(uptr alignment,uptr size,const StackTrace & stack)173 void *lsan_memalign(uptr alignment, uptr size, const StackTrace &stack) {
174 if (UNLIKELY(!IsPowerOfTwo(alignment))) {
175 errno = errno_EINVAL;
176 if (AllocatorMayReturnNull())
177 return nullptr;
178 ReportInvalidAllocationAlignment(alignment, &stack);
179 }
180 return SetErrnoOnNull(Allocate(stack, size, alignment, kAlwaysClearMemory));
181 }
182
lsan_malloc(uptr size,const StackTrace & stack)183 void *lsan_malloc(uptr size, const StackTrace &stack) {
184 return SetErrnoOnNull(Allocate(stack, size, 1, kAlwaysClearMemory));
185 }
186
lsan_free(void * p)187 void lsan_free(void *p) {
188 Deallocate(p);
189 }
190
lsan_realloc(void * p,uptr size,const StackTrace & stack)191 void *lsan_realloc(void *p, uptr size, const StackTrace &stack) {
192 return SetErrnoOnNull(Reallocate(stack, p, size, 1));
193 }
194
lsan_reallocarray(void * ptr,uptr nmemb,uptr size,const StackTrace & stack)195 void *lsan_reallocarray(void *ptr, uptr nmemb, uptr size,
196 const StackTrace &stack) {
197 if (UNLIKELY(CheckForCallocOverflow(size, nmemb))) {
198 errno = errno_ENOMEM;
199 if (AllocatorMayReturnNull())
200 return nullptr;
201 ReportReallocArrayOverflow(nmemb, size, &stack);
202 }
203 return lsan_realloc(ptr, nmemb * size, stack);
204 }
205
lsan_calloc(uptr nmemb,uptr size,const StackTrace & stack)206 void *lsan_calloc(uptr nmemb, uptr size, const StackTrace &stack) {
207 return SetErrnoOnNull(Calloc(nmemb, size, stack));
208 }
209
lsan_valloc(uptr size,const StackTrace & stack)210 void *lsan_valloc(uptr size, const StackTrace &stack) {
211 return SetErrnoOnNull(
212 Allocate(stack, size, GetPageSizeCached(), kAlwaysClearMemory));
213 }
214
lsan_pvalloc(uptr size,const StackTrace & stack)215 void *lsan_pvalloc(uptr size, const StackTrace &stack) {
216 uptr PageSize = GetPageSizeCached();
217 if (UNLIKELY(CheckForPvallocOverflow(size, PageSize))) {
218 errno = errno_ENOMEM;
219 if (AllocatorMayReturnNull())
220 return nullptr;
221 ReportPvallocOverflow(size, &stack);
222 }
223 // pvalloc(0) should allocate one page.
224 size = size ? RoundUpTo(size, PageSize) : PageSize;
225 return SetErrnoOnNull(Allocate(stack, size, PageSize, kAlwaysClearMemory));
226 }
227
lsan_mz_size(const void * p)228 uptr lsan_mz_size(const void *p) {
229 return GetMallocUsableSize(p);
230 }
231
232 ///// Interface to the common LSan module. /////
233
LockAllocator()234 void LockAllocator() {
235 allocator.ForceLock();
236 }
237
UnlockAllocator()238 void UnlockAllocator() {
239 allocator.ForceUnlock();
240 }
241
GetAllocatorGlobalRange(uptr * begin,uptr * end)242 void GetAllocatorGlobalRange(uptr *begin, uptr *end) {
243 *begin = (uptr)&allocator;
244 *end = *begin + sizeof(allocator);
245 }
246
PointsIntoChunk(void * p)247 uptr PointsIntoChunk(void* p) {
248 uptr addr = reinterpret_cast<uptr>(p);
249 uptr chunk = reinterpret_cast<uptr>(allocator.GetBlockBeginFastLocked(p));
250 if (!chunk) return 0;
251 // LargeMmapAllocator considers pointers to the meta-region of a chunk to be
252 // valid, but we don't want that.
253 if (addr < chunk) return 0;
254 ChunkMetadata *m = Metadata(reinterpret_cast<void *>(chunk));
255 CHECK(m);
256 if (!m->allocated)
257 return 0;
258 if (addr < chunk + m->requested_size)
259 return chunk;
260 if (IsSpecialCaseOfOperatorNew0(chunk, m->requested_size, addr))
261 return chunk;
262 return 0;
263 }
264
GetUserBegin(uptr chunk)265 uptr GetUserBegin(uptr chunk) {
266 return chunk;
267 }
268
LsanMetadata(uptr chunk)269 LsanMetadata::LsanMetadata(uptr chunk) {
270 metadata_ = Metadata(reinterpret_cast<void *>(chunk));
271 CHECK(metadata_);
272 }
273
allocated() const274 bool LsanMetadata::allocated() const {
275 return reinterpret_cast<ChunkMetadata *>(metadata_)->allocated;
276 }
277
tag() const278 ChunkTag LsanMetadata::tag() const {
279 return reinterpret_cast<ChunkMetadata *>(metadata_)->tag;
280 }
281
set_tag(ChunkTag value)282 void LsanMetadata::set_tag(ChunkTag value) {
283 reinterpret_cast<ChunkMetadata *>(metadata_)->tag = value;
284 }
285
requested_size() const286 uptr LsanMetadata::requested_size() const {
287 return reinterpret_cast<ChunkMetadata *>(metadata_)->requested_size;
288 }
289
stack_trace_id() const290 u32 LsanMetadata::stack_trace_id() const {
291 return reinterpret_cast<ChunkMetadata *>(metadata_)->stack_trace_id;
292 }
293
ForEachChunk(ForEachChunkCallback callback,void * arg)294 void ForEachChunk(ForEachChunkCallback callback, void *arg) {
295 allocator.ForEachChunk(callback, arg);
296 }
297
IgnoreObjectLocked(const void * p)298 IgnoreObjectResult IgnoreObjectLocked(const void *p) {
299 void *chunk = allocator.GetBlockBegin(p);
300 if (!chunk || p < chunk) return kIgnoreObjectInvalid;
301 ChunkMetadata *m = Metadata(chunk);
302 CHECK(m);
303 if (m->allocated && (uptr)p < (uptr)chunk + m->requested_size) {
304 if (m->tag == kIgnored)
305 return kIgnoreObjectAlreadyIgnored;
306 m->tag = kIgnored;
307 return kIgnoreObjectSuccess;
308 } else {
309 return kIgnoreObjectInvalid;
310 }
311 }
312 } // namespace __lsan
313
314 using namespace __lsan;
315
316 extern "C" {
317 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_current_allocated_bytes()318 uptr __sanitizer_get_current_allocated_bytes() {
319 uptr stats[AllocatorStatCount];
320 allocator.GetStats(stats);
321 return stats[AllocatorStatAllocated];
322 }
323
324 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_heap_size()325 uptr __sanitizer_get_heap_size() {
326 uptr stats[AllocatorStatCount];
327 allocator.GetStats(stats);
328 return stats[AllocatorStatMapped];
329 }
330
331 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_free_bytes()332 uptr __sanitizer_get_free_bytes() { return 0; }
333
334 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_unmapped_bytes()335 uptr __sanitizer_get_unmapped_bytes() { return 0; }
336
337 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_estimated_allocated_size(uptr size)338 uptr __sanitizer_get_estimated_allocated_size(uptr size) { return size; }
339
340 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_ownership(const void * p)341 int __sanitizer_get_ownership(const void *p) { return Metadata(p) != nullptr; }
342
343 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_get_allocated_size(const void * p)344 uptr __sanitizer_get_allocated_size(const void *p) {
345 return GetMallocUsableSize(p);
346 }
347
348 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
349 // Provide default (no-op) implementation of malloc hooks.
350 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
__sanitizer_malloc_hook(void * ptr,uptr size)351 void __sanitizer_malloc_hook(void *ptr, uptr size) {
352 (void)ptr;
353 (void)size;
354 }
355 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
__sanitizer_free_hook(void * ptr)356 void __sanitizer_free_hook(void *ptr) {
357 (void)ptr;
358 }
359 #endif
360 } // extern "C"
361