Bug Summary

File:compiler-rt/lib/lsan/lsan_common.cpp
Warning:line 778, column 3
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple i386-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name lsan_common.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu i686 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/projects/compiler-rt/lib/lsan -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/projects/compiler-rt/lib/lsan -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/.. -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/32 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-unused-parameter -Wno-variadic-macros -Wno-format-pedantic -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/projects/compiler-rt/lib/lsan -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0=. -ferror-limit 19 -fvisibility hidden -fvisibility-inlines-hidden -fno-builtin -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-08-28-193554-24367-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp

/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp

→
1//=-- lsan_common.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// Implementation of common leak checking functionality.
11//
12//===----------------------------------------------------------------------===//
13
14#include "lsan_common.h"
15
16#include "sanitizer_common/sanitizer_common.h"
17#include "sanitizer_common/sanitizer_flag_parser.h"
18#include "sanitizer_common/sanitizer_flags.h"
19#include "sanitizer_common/sanitizer_placement_new.h"
20#include "sanitizer_common/sanitizer_procmaps.h"
21#include "sanitizer_common/sanitizer_report_decorator.h"
22#include "sanitizer_common/sanitizer_stackdepot.h"
23#include "sanitizer_common/sanitizer_stacktrace.h"
24#include "sanitizer_common/sanitizer_suppressions.h"
25#include "sanitizer_common/sanitizer_thread_registry.h"
26#include "sanitizer_common/sanitizer_tls_get_addr.h"
27
28#if CAN_SANITIZE_LEAKS1
29namespace __lsan {
30
31// This mutex is used to prevent races between DoLeakCheck and IgnoreObject, and
32// also to protect the global list of root regions.
33Mutex global_mutex;
34
35Flags lsan_flags;
36
37
38void DisableCounterUnderflow() {
39 if (common_flags()->detect_leaks) {
40 Report("Unmatched call to __lsan_enable().\n");
41 Die();
42 }
43}
44
45void Flags::SetDefaults() {
46#define LSAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
47#include "lsan_flags.inc"
48#undef LSAN_FLAG
49}
50
51void RegisterLsanFlags(FlagParser *parser, Flags *f) {
52#define LSAN_FLAG(Type, Name, DefaultValue, Description) \
53 RegisterFlag(parser, #Name, Description, &f->Name);
54#include "lsan_flags.inc"
55#undef LSAN_FLAG
56}
57
58#define LOG_POINTERS(...)do { if (flags()->log_pointers) Report(...); } while (0) \
59 do { \
60 if (flags()->log_pointers) Report(__VA_ARGS__); \
61 } while (0)
62
63#define LOG_THREADS(...)do { if (flags()->log_threads) Report(...); } while (0) \
64 do { \
65 if (flags()->log_threads) Report(__VA_ARGS__); \
66 } while (0)
67
68class LeakSuppressionContext {
69 bool parsed = false;
70 SuppressionContext context;
71 bool suppressed_stacks_sorted = true;
72 InternalMmapVector<u32> suppressed_stacks;
73
74 Suppression *GetSuppressionForAddr(uptr addr);
75 void LazyInit();
76
77 public:
78 LeakSuppressionContext(const char *supprression_types[],
79 int suppression_types_num)
80 : context(supprression_types, suppression_types_num) {}
81
82 Suppression *GetSuppressionForStack(u32 stack_trace_id);
83
84 const InternalMmapVector<u32> &GetSortedSuppressedStacks() {
85 if (!suppressed_stacks_sorted) {
86 suppressed_stacks_sorted = true;
87 SortAndDedup(suppressed_stacks);
88 }
89 return suppressed_stacks;
90 }
91 void PrintMatchedSuppressions();
92};
93
94ALIGNED(64)__attribute__((aligned(64))) static char suppression_placeholder[sizeof(LeakSuppressionContext)];
95static LeakSuppressionContext *suppression_ctx = nullptr;
96static const char kSuppressionLeak[] = "leak";
97static const char *kSuppressionTypes[] = { kSuppressionLeak };
98static const char kStdSuppressions[] =
99#if SANITIZER_SUPPRESS_LEAK_ON_PTHREAD_EXIT0
100 // For more details refer to the SANITIZER_SUPPRESS_LEAK_ON_PTHREAD_EXIT
101 // definition.
102 "leak:*pthread_exit*\n"
103#endif // SANITIZER_SUPPRESS_LEAK_ON_PTHREAD_EXIT
104#if SANITIZER_MAC0
105 // For Darwin and os_log/os_trace: https://reviews.llvm.org/D35173
106 "leak:*_os_trace*\n"
107#endif
108 // TLS leak in some glibc versions, described in
109 // https://sourceware.org/bugzilla/show_bug.cgi?id=12650.
110 "leak:*tls_get_addr*\n";
111
112void InitializeSuppressions() {
113 CHECK_EQ(nullptr, suppression_ctx)do { __sanitizer::u64 v1 = (__sanitizer::u64)((nullptr)); __sanitizer
::u64 v2 = (__sanitizer::u64)((suppression_ctx)); if (__builtin_expect
(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 113, "(" "(nullptr)" ") " "==" " (" "(suppression_ctx)" ")"
, v1, v2); } while (false);
114 suppression_ctx = new (suppression_placeholder)
115 LeakSuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes)(sizeof(kSuppressionTypes)/sizeof((kSuppressionTypes)[0])));
116}
117
118void LeakSuppressionContext::LazyInit() {
119 if (!parsed) {
120 parsed = true;
121 context.ParseFromFile(flags()->suppressions);
122 if (&__lsan_default_suppressions)
123 context.Parse(__lsan_default_suppressions());
124 context.Parse(kStdSuppressions);
125 }
126}
127
128static LeakSuppressionContext *GetSuppressionContext() {
129 CHECK(suppression_ctx)do { __sanitizer::u64 v1 = (__sanitizer::u64)((suppression_ctx
)); __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 129, "(" "(suppression_ctx)" ") " "!=" " (" "0" ")", v1, v2
); } while (false);
130 return suppression_ctx;
131}
132
133static InternalMmapVector<RootRegion> *root_regions;
134
135InternalMmapVector<RootRegion> const *GetRootRegions() { return root_regions; }
136
137void InitializeRootRegions() {
138 CHECK(!root_regions)do { __sanitizer::u64 v1 = (__sanitizer::u64)((!root_regions)
); __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 138, "(" "(!root_regions)" ") " "!=" " (" "0" ")", v1, v2);
} while (false);
139 ALIGNED(64)__attribute__((aligned(64))) static char placeholder[sizeof(InternalMmapVector<RootRegion>)];
140 root_regions = new (placeholder) InternalMmapVector<RootRegion>();
141}
142
143void InitCommonLsan() {
144 InitializeRootRegions();
145 if (common_flags()->detect_leaks) {
146 // Initialization which can fail or print warnings should only be done if
147 // LSan is actually enabled.
148 InitializeSuppressions();
149 InitializePlatformSpecificModules();
150 }
151}
152
153class Decorator: public __sanitizer::SanitizerCommonDecorator {
154 public:
155 Decorator() : SanitizerCommonDecorator() { }
156 const char *Error() { return Red(); }
157 const char *Leak() { return Blue(); }
158};
159
160static inline bool CanBeAHeapPointer(uptr p) {
161 // Since our heap is located in mmap-ed memory, we can assume a sensible lower
162 // bound on heap addresses.
163 const uptr kMinAddress = 4 * 4096;
164 if (p < kMinAddress) return false;
165#if defined(__x86_64__)
166 // Accept only canonical form user-space addresses.
167 return ((p >> 47) == 0);
168#elif defined(__mips64)
169 return ((p >> 40) == 0);
170#elif defined(__aarch64__)
171 unsigned runtimeVMA =
172 (MostSignificantSetBitIndex(GET_CURRENT_FRAME()(__sanitizer::uptr) __builtin_frame_address(0)) + 1);
173 return ((p >> runtimeVMA) == 0);
174#else
175 return true;
176#endif
177}
178
179// Scans the memory range, looking for byte patterns that point into allocator
180// chunks. Marks those chunks with |tag| and adds them to |frontier|.
181// There are two usage modes for this function: finding reachable chunks
182// (|tag| = kReachable) and finding indirectly leaked chunks
183// (|tag| = kIndirectlyLeaked). In the second case, there's no flood fill,
184// so |frontier| = 0.
185void ScanRangeForPointers(uptr begin, uptr end,
186 Frontier *frontier,
187 const char *region_type, ChunkTag tag) {
188 CHECK(tag == kReachable || tag == kIndirectlyLeaked)do { __sanitizer::u64 v1 = (__sanitizer::u64)((tag == kReachable
|| tag == kIndirectlyLeaked)); __sanitizer::u64 v2 = (__sanitizer
::u64)(0); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer
::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 188, "(" "(tag == kReachable || tag == kIndirectlyLeaked)" ") "
"!=" " (" "0" ")", v1, v2); } while (false);
189 const uptr alignment = flags()->pointer_alignment();
190 LOG_POINTERS("Scanning %s range %p-%p.\n", region_type, begin, end)do { if (flags()->log_pointers) Report("Scanning %s range %p-%p.\n"
, region_type, begin, end); } while (0);
191 uptr pp = begin;
192 if (pp % alignment)
193 pp = pp + alignment - pp % alignment;
194 for (; pp + sizeof(void *) <= end; pp += alignment) {
195 void *p = *reinterpret_cast<void **>(pp);
196 if (!CanBeAHeapPointer(reinterpret_cast<uptr>(p))) continue;
197 uptr chunk = PointsIntoChunk(p);
198 if (!chunk) continue;
199 // Pointers to self don't count. This matters when tag == kIndirectlyLeaked.
200 if (chunk == begin) continue;
201 LsanMetadata m(chunk);
202 if (m.tag() == kReachable || m.tag() == kIgnored) continue;
203
204 // Do this check relatively late so we can log only the interesting cases.
205 if (!flags()->use_poisoned && WordIsPoisoned(pp)) {
206 LOG_POINTERS(do { if (flags()->log_pointers) Report("%p is poisoned: ignoring %p pointing into chunk %p-%p of size "
"%zu.\n", pp, p, chunk, chunk + m.requested_size(), m.requested_size
()); } while (0)
207 "%p is poisoned: ignoring %p pointing into chunk %p-%p of size "do { if (flags()->log_pointers) Report("%p is poisoned: ignoring %p pointing into chunk %p-%p of size "
"%zu.\n", pp, p, chunk, chunk + m.requested_size(), m.requested_size
()); } while (0)
208 "%zu.\n",do { if (flags()->log_pointers) Report("%p is poisoned: ignoring %p pointing into chunk %p-%p of size "
"%zu.\n", pp, p, chunk, chunk + m.requested_size(), m.requested_size
()); } while (0)
209 pp, p, chunk, chunk + m.requested_size(), m.requested_size())do { if (flags()->log_pointers) Report("%p is poisoned: ignoring %p pointing into chunk %p-%p of size "
"%zu.\n", pp, p, chunk, chunk + m.requested_size(), m.requested_size
()); } while (0);
210 continue;
211 }
212
213 m.set_tag(tag);
214 LOG_POINTERS("%p: found %p pointing into chunk %p-%p of size %zu.\n", pp, p,do { if (flags()->log_pointers) Report("%p: found %p pointing into chunk %p-%p of size %zu.\n"
, pp, p, chunk, chunk + m.requested_size(), m.requested_size(
)); } while (0)
215 chunk, chunk + m.requested_size(), m.requested_size())do { if (flags()->log_pointers) Report("%p: found %p pointing into chunk %p-%p of size %zu.\n"
, pp, p, chunk, chunk + m.requested_size(), m.requested_size(
)); } while (0);
216 if (frontier)
217 frontier->push_back(chunk);
218 }
219}
220
221// Scans a global range for pointers
222void ScanGlobalRange(uptr begin, uptr end, Frontier *frontier) {
223 uptr allocator_begin = 0, allocator_end = 0;
224 GetAllocatorGlobalRange(&allocator_begin, &allocator_end);
225 if (begin <= allocator_begin && allocator_begin < end) {
226 CHECK_LE(allocator_begin, allocator_end)do { __sanitizer::u64 v1 = (__sanitizer::u64)((allocator_begin
)); __sanitizer::u64 v2 = (__sanitizer::u64)((allocator_end))
; if (__builtin_expect(!!(!(v1 <= v2)), 0)) __sanitizer::CheckFailed
("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 226, "(" "(allocator_begin)" ") " "<=" " (" "(allocator_end)"
")", v1, v2); } while (false);
227 CHECK_LE(allocator_end, end)do { __sanitizer::u64 v1 = (__sanitizer::u64)((allocator_end)
); __sanitizer::u64 v2 = (__sanitizer::u64)((end)); if (__builtin_expect
(!!(!(v1 <= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 227, "(" "(allocator_end)" ") " "<=" " (" "(end)" ")", v1
, v2); } while (false);
228 if (begin < allocator_begin)
229 ScanRangeForPointers(begin, allocator_begin, frontier, "GLOBAL",
230 kReachable);
231 if (allocator_end < end)
232 ScanRangeForPointers(allocator_end, end, frontier, "GLOBAL", kReachable);
233 } else {
234 ScanRangeForPointers(begin, end, frontier, "GLOBAL", kReachable);
235 }
236}
237
238void ForEachExtraStackRangeCb(uptr begin, uptr end, void* arg) {
239 Frontier *frontier = reinterpret_cast<Frontier *>(arg);
240 ScanRangeForPointers(begin, end, frontier, "FAKE STACK", kReachable);
241}
242
243#if SANITIZER_FUCHSIA0
244
245// Fuchsia handles all threads together with its own callback.
246static void ProcessThreads(SuspendedThreadsList const &, Frontier *) {}
247
248#else
249
250#if SANITIZER_ANDROID0
251// FIXME: Move this out into *libcdep.cpp
252extern "C" SANITIZER_WEAK_ATTRIBUTE__attribute__((weak)) void __libc_iterate_dynamic_tls(
253 pid_t, void (*cb)(void *, void *, uptr, void *), void *);
254#endif
255
256static void ProcessThreadRegistry(Frontier *frontier) {
257 InternalMmapVector<uptr> ptrs;
258 GetThreadRegistryLocked()->RunCallbackForEachThreadLocked(
259 GetAdditionalThreadContextPtrs, &ptrs);
260
261 for (uptr i = 0; i < ptrs.size(); ++i) {
262 void *ptr = reinterpret_cast<void *>(ptrs[i]);
263 uptr chunk = PointsIntoChunk(ptr);
264 if (!chunk)
265 continue;
266 LsanMetadata m(chunk);
267 if (!m.allocated())
268 continue;
269
270 // Mark as reachable and add to frontier.
271 LOG_POINTERS("Treating pointer %p from ThreadContext as reachable\n", ptr)do { if (flags()->log_pointers) Report("Treating pointer %p from ThreadContext as reachable\n"
, ptr); } while (0);
272 m.set_tag(kReachable);
273 frontier->push_back(chunk);
274 }
275}
276
277// Scans thread data (stacks and TLS) for heap pointers.
278static void ProcessThreads(SuspendedThreadsList const &suspended_threads,
279 Frontier *frontier) {
280 InternalMmapVector<uptr> registers;
281 for (uptr i = 0; i < suspended_threads.ThreadCount(); i++) {
282 tid_t os_id = static_cast<tid_t>(suspended_threads.GetThreadID(i));
283 LOG_THREADS("Processing thread %d.\n", os_id)do { if (flags()->log_threads) Report("Processing thread %d.\n"
, os_id); } while (0);
284 uptr stack_begin, stack_end, tls_begin, tls_end, cache_begin, cache_end;
285 DTLS *dtls;
286 bool thread_found = GetThreadRangesLocked(os_id, &stack_begin, &stack_end,
287 &tls_begin, &tls_end,
288 &cache_begin, &cache_end, &dtls);
289 if (!thread_found) {
290 // If a thread can't be found in the thread registry, it's probably in the
291 // process of destruction. Log this event and move on.
292 LOG_THREADS("Thread %d not found in registry.\n", os_id)do { if (flags()->log_threads) Report("Thread %d not found in registry.\n"
, os_id); } while (0);
293 continue;
294 }
295 uptr sp;
296 PtraceRegistersStatus have_registers =
297 suspended_threads.GetRegistersAndSP(i, &registers, &sp);
298 if (have_registers != REGISTERS_AVAILABLE) {
299 Report("Unable to get registers from thread %d.\n", os_id);
300 // If unable to get SP, consider the entire stack to be reachable unless
301 // GetRegistersAndSP failed with ESRCH.
302 if (have_registers == REGISTERS_UNAVAILABLE_FATAL) continue;
303 sp = stack_begin;
304 }
305
306 if (flags()->use_registers && have_registers) {
307 uptr registers_begin = reinterpret_cast<uptr>(registers.data());
308 uptr registers_end =
309 reinterpret_cast<uptr>(registers.data() + registers.size());
310 ScanRangeForPointers(registers_begin, registers_end, frontier,
311 "REGISTERS", kReachable);
312 }
313
314 if (flags()->use_stacks) {
315 LOG_THREADS("Stack at %p-%p (SP = %p).\n", stack_begin, stack_end, sp)do { if (flags()->log_threads) Report("Stack at %p-%p (SP = %p).\n"
, stack_begin, stack_end, sp); } while (0);
316 if (sp < stack_begin || sp >= stack_end) {
317 // SP is outside the recorded stack range (e.g. the thread is running a
318 // signal handler on alternate stack, or swapcontext was used).
319 // Again, consider the entire stack range to be reachable.
320 LOG_THREADS("WARNING: stack pointer not in stack range.\n")do { if (flags()->log_threads) Report("WARNING: stack pointer not in stack range.\n"
); } while (0);
321 uptr page_size = GetPageSizeCached();
322 int skipped = 0;
323 while (stack_begin < stack_end &&
324 !IsAccessibleMemoryRange(stack_begin, 1)) {
325 skipped++;
326 stack_begin += page_size;
327 }
328 LOG_THREADS("Skipped %d guard page(s) to obtain stack %p-%p.\n",do { if (flags()->log_threads) Report("Skipped %d guard page(s) to obtain stack %p-%p.\n"
, skipped, stack_begin, stack_end); } while (0)
329 skipped, stack_begin, stack_end)do { if (flags()->log_threads) Report("Skipped %d guard page(s) to obtain stack %p-%p.\n"
, skipped, stack_begin, stack_end); } while (0);
330 } else {
331 // Shrink the stack range to ignore out-of-scope values.
332 stack_begin = sp;
333 }
334 ScanRangeForPointers(stack_begin, stack_end, frontier, "STACK",
335 kReachable);
336 ForEachExtraStackRange(os_id, ForEachExtraStackRangeCb, frontier);
337 }
338
339 if (flags()->use_tls) {
340 if (tls_begin) {
341 LOG_THREADS("TLS at %p-%p.\n", tls_begin, tls_end)do { if (flags()->log_threads) Report("TLS at %p-%p.\n", tls_begin
, tls_end); } while (0);
342 // If the tls and cache ranges don't overlap, scan full tls range,
343 // otherwise, only scan the non-overlapping portions
344 if (cache_begin == cache_end || tls_end < cache_begin ||
345 tls_begin > cache_end) {
346 ScanRangeForPointers(tls_begin, tls_end, frontier, "TLS", kReachable);
347 } else {
348 if (tls_begin < cache_begin)
349 ScanRangeForPointers(tls_begin, cache_begin, frontier, "TLS",
350 kReachable);
351 if (tls_end > cache_end)
352 ScanRangeForPointers(cache_end, tls_end, frontier, "TLS",
353 kReachable);
354 }
355 }
356#if SANITIZER_ANDROID0
357 auto *cb = +[](void *dtls_begin, void *dtls_end, uptr /*dso_idd*/,
358 void *arg) -> void {
359 ScanRangeForPointers(reinterpret_cast<uptr>(dtls_begin),
360 reinterpret_cast<uptr>(dtls_end),
361 reinterpret_cast<Frontier *>(arg), "DTLS",
362 kReachable);
363 };
364
365 // FIXME: There might be a race-condition here (and in Bionic) if the
366 // thread is suspended in the middle of updating its DTLS. IOWs, we
367 // could scan already freed memory. (probably fine for now)
368 __libc_iterate_dynamic_tls(os_id, cb, frontier);
369#else
370 if (dtls && !DTLSInDestruction(dtls)) {
371 ForEachDVT(dtls, [&](const DTLS::DTV &dtv, int id) {
372 uptr dtls_beg = dtv.beg;
373 uptr dtls_end = dtls_beg + dtv.size;
374 if (dtls_beg < dtls_end) {
375 LOG_THREADS("DTLS %zu at %p-%p.\n", id, dtls_beg, dtls_end)do { if (flags()->log_threads) Report("DTLS %zu at %p-%p.\n"
, id, dtls_beg, dtls_end); } while (0);
376 ScanRangeForPointers(dtls_beg, dtls_end, frontier, "DTLS",
377 kReachable);
378 }
379 });
380 } else {
381 // We are handling a thread with DTLS under destruction. Log about
382 // this and continue.
383 LOG_THREADS("Thread %d has DTLS under destruction.\n", os_id)do { if (flags()->log_threads) Report("Thread %d has DTLS under destruction.\n"
, os_id); } while (0);
384 }
385#endif
386 }
387 }
388
389 // Add pointers reachable from ThreadContexts
390 ProcessThreadRegistry(frontier);
391}
392
393#endif // SANITIZER_FUCHSIA
394
395void ScanRootRegion(Frontier *frontier, const RootRegion &root_region,
396 uptr region_begin, uptr region_end, bool is_readable) {
397 uptr intersection_begin = Max(root_region.begin, region_begin);
398 uptr intersection_end = Min(region_end, root_region.begin + root_region.size);
399 if (intersection_begin >= intersection_end) return;
400 LOG_POINTERS("Root region %p-%p intersects with mapped region %p-%p (%s)\n",do { if (flags()->log_pointers) Report("Root region %p-%p intersects with mapped region %p-%p (%s)\n"
, root_region.begin, root_region.begin + root_region.size, region_begin
, region_end, is_readable ? "readable" : "unreadable"); } while
(0)
401 root_region.begin, root_region.begin + root_region.size,do { if (flags()->log_pointers) Report("Root region %p-%p intersects with mapped region %p-%p (%s)\n"
, root_region.begin, root_region.begin + root_region.size, region_begin
, region_end, is_readable ? "readable" : "unreadable"); } while
(0)
402 region_begin, region_end,do { if (flags()->log_pointers) Report("Root region %p-%p intersects with mapped region %p-%p (%s)\n"
, root_region.begin, root_region.begin + root_region.size, region_begin
, region_end, is_readable ? "readable" : "unreadable"); } while
(0)
403 is_readable ? "readable" : "unreadable")do { if (flags()->log_pointers) Report("Root region %p-%p intersects with mapped region %p-%p (%s)\n"
, root_region.begin, root_region.begin + root_region.size, region_begin
, region_end, is_readable ? "readable" : "unreadable"); } while
(0);
404 if (is_readable)
405 ScanRangeForPointers(intersection_begin, intersection_end, frontier, "ROOT",
406 kReachable);
407}
408
409static void ProcessRootRegion(Frontier *frontier,
410 const RootRegion &root_region) {
411 MemoryMappingLayout proc_maps(/*cache_enabled*/ true);
412 MemoryMappedSegment segment;
413 while (proc_maps.Next(&segment)) {
414 ScanRootRegion(frontier, root_region, segment.start, segment.end,
415 segment.IsReadable());
416 }
417}
418
419// Scans root regions for heap pointers.
420static void ProcessRootRegions(Frontier *frontier) {
421 if (!flags()->use_root_regions) return;
422 CHECK(root_regions)do { __sanitizer::u64 v1 = (__sanitizer::u64)((root_regions))
; __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 422, "(" "(root_regions)" ") " "!=" " (" "0" ")", v1, v2); }
while (false);
423 for (uptr i = 0; i < root_regions->size(); i++) {
424 ProcessRootRegion(frontier, (*root_regions)[i]);
425 }
426}
427
428static void FloodFillTag(Frontier *frontier, ChunkTag tag) {
429 while (frontier->size()) {
430 uptr next_chunk = frontier->back();
431 frontier->pop_back();
432 LsanMetadata m(next_chunk);
433 ScanRangeForPointers(next_chunk, next_chunk + m.requested_size(), frontier,
434 "HEAP", tag);
435 }
436}
437
438// ForEachChunk callback. If the chunk is marked as leaked, marks all chunks
439// which are reachable from it as indirectly leaked.
440static void MarkIndirectlyLeakedCb(uptr chunk, void *arg) {
441 chunk = GetUserBegin(chunk);
442 LsanMetadata m(chunk);
443 if (m.allocated() && m.tag() != kReachable) {
444 ScanRangeForPointers(chunk, chunk + m.requested_size(),
445 /* frontier */ nullptr, "HEAP", kIndirectlyLeaked);
446 }
447}
448
449static void IgnoredSuppressedCb(uptr chunk, void *arg) {
450 CHECK(arg)do { __sanitizer::u64 v1 = (__sanitizer::u64)((arg)); __sanitizer
::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1
!= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 450, "(" "(arg)" ") " "!=" " (" "0" ")", v1, v2); } while (
false);
451 chunk = GetUserBegin(chunk);
452 LsanMetadata m(chunk);
453 if (!m.allocated() || m.tag() == kIgnored)
454 return;
455
456 const InternalMmapVector<u32> &suppressed =
457 *static_cast<const InternalMmapVector<u32> *>(arg);
458 uptr idx = InternalLowerBound(suppressed, m.stack_trace_id());
459 if (idx >= suppressed.size() || m.stack_trace_id() != suppressed[idx])
460 return;
461
462 LOG_POINTERS("Suppressed: chunk %p-%p of size %zu.\n", chunk,do { if (flags()->log_pointers) Report("Suppressed: chunk %p-%p of size %zu.\n"
, chunk, chunk + m.requested_size(), m.requested_size()); } while
(0)
463 chunk + m.requested_size(), m.requested_size())do { if (flags()->log_pointers) Report("Suppressed: chunk %p-%p of size %zu.\n"
, chunk, chunk + m.requested_size(), m.requested_size()); } while
(0);
464 m.set_tag(kIgnored);
465}
466
467// ForEachChunk callback. If chunk is marked as ignored, adds its address to
468// frontier.
469static void CollectIgnoredCb(uptr chunk, void *arg) {
470 CHECK(arg)do { __sanitizer::u64 v1 = (__sanitizer::u64)((arg)); __sanitizer
::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1
!= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 470, "(" "(arg)" ") " "!=" " (" "0" ")", v1, v2); } while (
false);
471 chunk = GetUserBegin(chunk);
472 LsanMetadata m(chunk);
473 if (m.allocated() && m.tag() == kIgnored) {
474 LOG_POINTERS("Ignored: chunk %p-%p of size %zu.\n",do { if (flags()->log_pointers) Report("Ignored: chunk %p-%p of size %zu.\n"
, chunk, chunk + m.requested_size(), m.requested_size()); } while
(0)
475 chunk, chunk + m.requested_size(), m.requested_size())do { if (flags()->log_pointers) Report("Ignored: chunk %p-%p of size %zu.\n"
, chunk, chunk + m.requested_size(), m.requested_size()); } while
(0);
476 reinterpret_cast<Frontier *>(arg)->push_back(chunk);
477 }
478}
479
480static uptr GetCallerPC(u32 stack_id, StackDepotReverseMap *map) {
481 CHECK(stack_id)do { __sanitizer::u64 v1 = (__sanitizer::u64)((stack_id)); __sanitizer
::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1
!= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 481, "(" "(stack_id)" ") " "!=" " (" "0" ")", v1, v2); } while
(false);
482 StackTrace stack = map->Get(stack_id);
483 // The top frame is our malloc/calloc/etc. The next frame is the caller.
484 if (stack.size >= 2)
485 return stack.trace[1];
486 return 0;
487}
488
489struct InvalidPCParam {
490 Frontier *frontier;
491 StackDepotReverseMap *stack_depot_reverse_map;
492 bool skip_linker_allocations;
493};
494
495// ForEachChunk callback. If the caller pc is invalid or is within the linker,
496// mark as reachable. Called by ProcessPlatformSpecificAllocations.
497static void MarkInvalidPCCb(uptr chunk, void *arg) {
498 CHECK(arg)do { __sanitizer::u64 v1 = (__sanitizer::u64)((arg)); __sanitizer
::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1
!= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 498, "(" "(arg)" ") " "!=" " (" "0" ")", v1, v2); } while (
false);
499 InvalidPCParam *param = reinterpret_cast<InvalidPCParam *>(arg);
500 chunk = GetUserBegin(chunk);
501 LsanMetadata m(chunk);
502 if (m.allocated() && m.tag() != kReachable && m.tag() != kIgnored) {
503 u32 stack_id = m.stack_trace_id();
504 uptr caller_pc = 0;
505 if (stack_id > 0)
506 caller_pc = GetCallerPC(stack_id, param->stack_depot_reverse_map);
507 // If caller_pc is unknown, this chunk may be allocated in a coroutine. Mark
508 // it as reachable, as we can't properly report its allocation stack anyway.
509 if (caller_pc == 0 || (param->skip_linker_allocations &&
510 GetLinker()->containsAddress(caller_pc))) {
511 m.set_tag(kReachable);
512 param->frontier->push_back(chunk);
513 }
514 }
515}
516
517// On Linux, treats all chunks allocated from ld-linux.so as reachable, which
518// covers dynamically allocated TLS blocks, internal dynamic loader's loaded
519// modules accounting etc.
520// Dynamic TLS blocks contain the TLS variables of dynamically loaded modules.
521// They are allocated with a __libc_memalign() call in allocate_and_init()
522// (elf/dl-tls.c). Glibc won't tell us the address ranges occupied by those
523// blocks, but we can make sure they come from our own allocator by intercepting
524// __libc_memalign(). On top of that, there is no easy way to reach them. Their
525// addresses are stored in a dynamically allocated array (the DTV) which is
526// referenced from the static TLS. Unfortunately, we can't just rely on the DTV
527// being reachable from the static TLS, and the dynamic TLS being reachable from
528// the DTV. This is because the initial DTV is allocated before our interception
529// mechanism kicks in, and thus we don't recognize it as allocated memory. We
530// can't special-case it either, since we don't know its size.
531// Our solution is to include in the root set all allocations made from
532// ld-linux.so (which is where allocate_and_init() is implemented). This is
533// guaranteed to include all dynamic TLS blocks (and possibly other allocations
534// which we don't care about).
535// On all other platforms, this simply checks to ensure that the caller pc is
536// valid before reporting chunks as leaked.
537void ProcessPC(Frontier *frontier) {
538 StackDepotReverseMap stack_depot_reverse_map;
539 InvalidPCParam arg;
540 arg.frontier = frontier;
541 arg.stack_depot_reverse_map = &stack_depot_reverse_map;
542 arg.skip_linker_allocations =
543 flags()->use_tls && flags()->use_ld_allocations && GetLinker() != nullptr;
544 ForEachChunk(MarkInvalidPCCb, &arg);
545}
546
547// Sets the appropriate tag on each chunk.
548static void ClassifyAllChunks(SuspendedThreadsList const &suspended_threads,
549 Frontier *frontier) {
550 const InternalMmapVector<u32> &suppressed_stacks =
551 GetSuppressionContext()->GetSortedSuppressedStacks();
552 if (!suppressed_stacks.empty()) {
553 ForEachChunk(IgnoredSuppressedCb,
554 const_cast<InternalMmapVector<u32> *>(&suppressed_stacks));
555 }
556 ForEachChunk(CollectIgnoredCb, frontier);
557 ProcessGlobalRegions(frontier);
558 ProcessThreads(suspended_threads, frontier);
559 ProcessRootRegions(frontier);
560 FloodFillTag(frontier, kReachable);
561
562 CHECK_EQ(0, frontier->size())do { __sanitizer::u64 v1 = (__sanitizer::u64)((0)); __sanitizer
::u64 v2 = (__sanitizer::u64)((frontier->size())); if (__builtin_expect
(!!(!(v1 == v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 562, "(" "(0)" ") " "==" " (" "(frontier->size())" ")", v1
, v2); } while (false);
563 ProcessPC(frontier);
564
565 // The check here is relatively expensive, so we do this in a separate flood
566 // fill. That way we can skip the check for chunks that are reachable
567 // otherwise.
568 LOG_POINTERS("Processing platform-specific allocations.\n")do { if (flags()->log_pointers) Report("Processing platform-specific allocations.\n"
); } while (0);
569 ProcessPlatformSpecificAllocations(frontier);
570 FloodFillTag(frontier, kReachable);
571
572 // Iterate over leaked chunks and mark those that are reachable from other
573 // leaked chunks.
574 LOG_POINTERS("Scanning leaked chunks.\n")do { if (flags()->log_pointers) Report("Scanning leaked chunks.\n"
); } while (0);
575 ForEachChunk(MarkIndirectlyLeakedCb, nullptr);
576}
577
578// ForEachChunk callback. Resets the tags to pre-leak-check state.
579static void ResetTagsCb(uptr chunk, void *arg) {
580 (void)arg;
581 chunk = GetUserBegin(chunk);
582 LsanMetadata m(chunk);
583 if (m.allocated() && m.tag() != kIgnored)
584 m.set_tag(kDirectlyLeaked);
585}
586
587static void PrintStackTraceById(u32 stack_trace_id) {
588 CHECK(stack_trace_id)do { __sanitizer::u64 v1 = (__sanitizer::u64)((stack_trace_id
)); __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 588, "(" "(stack_trace_id)" ") " "!=" " (" "0" ")", v1, v2)
; } while (false);
589 StackDepotGet(stack_trace_id).Print();
590}
591
592// ForEachChunk callback. Aggregates information about unreachable chunks into
593// a LeakReport.
594static void CollectLeaksCb(uptr chunk, void *arg) {
595 CHECK(arg)do { __sanitizer::u64 v1 = (__sanitizer::u64)((arg)); __sanitizer
::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1
!= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 595, "(" "(arg)" ") " "!=" " (" "0" ")", v1, v2); } while (
false);
596 LeakReport *leak_report = reinterpret_cast<LeakReport *>(arg);
597 chunk = GetUserBegin(chunk);
598 LsanMetadata m(chunk);
599 if (!m.allocated()) return;
600 if (m.tag() == kDirectlyLeaked || m.tag() == kIndirectlyLeaked) {
601 u32 resolution = flags()->resolution;
602 u32 stack_trace_id = 0;
603 if (resolution > 0) {
604 StackTrace stack = StackDepotGet(m.stack_trace_id());
605 stack.size = Min(stack.size, resolution);
606 stack_trace_id = StackDepotPut(stack);
607 } else {
608 stack_trace_id = m.stack_trace_id();
609 }
610 leak_report->AddLeakedChunk(chunk, stack_trace_id, m.requested_size(),
611 m.tag());
612 }
613}
614
615void LeakSuppressionContext::PrintMatchedSuppressions() {
616 InternalMmapVector<Suppression *> matched;
617 context.GetMatched(&matched);
618 if (!matched.size())
619 return;
620 const char *line = "-----------------------------------------------------";
621 Printf("%s\n", line);
622 Printf("Suppressions used:\n");
623 Printf(" count bytes template\n");
624 for (uptr i = 0; i < matched.size(); i++) {
625 Printf("%7zu %10zu %s\n",
626 static_cast<uptr>(atomic_load_relaxed(&matched[i]->hit_count)),
627 matched[i]->weight, matched[i]->templ);
628 }
629 Printf("%s\n\n", line);
630}
631
632static void ReportIfNotSuspended(ThreadContextBase *tctx, void *arg) {
633 const InternalMmapVector<tid_t> &suspended_threads =
634 *(const InternalMmapVector<tid_t> *)arg;
635 if (tctx->status == ThreadStatusRunning) {
636 uptr i = InternalLowerBound(suspended_threads, tctx->os_id);
637 if (i >= suspended_threads.size() || suspended_threads[i] != tctx->os_id)
638 Report("Running thread %d was not suspended. False leaks are possible.\n",
639 tctx->os_id);
640 }
641}
642
643#if SANITIZER_FUCHSIA0
644
645// Fuchsia provides a libc interface that guarantees all threads are
646// covered, and SuspendedThreadList is never really used.
647static void ReportUnsuspendedThreads(const SuspendedThreadsList &) {}
648
649#else // !SANITIZER_FUCHSIA
650
651static void ReportUnsuspendedThreads(
652 const SuspendedThreadsList &suspended_threads) {
653 InternalMmapVector<tid_t> threads(suspended_threads.ThreadCount());
654 for (uptr i = 0; i < suspended_threads.ThreadCount(); ++i)
655 threads[i] = suspended_threads.GetThreadID(i);
656
657 Sort(threads.data(), threads.size());
658
659 GetThreadRegistryLocked()->RunCallbackForEachThreadLocked(
660 &ReportIfNotSuspended, &threads);
661}
662
663#endif // !SANITIZER_FUCHSIA
664
665static void CheckForLeaksCallback(const SuspendedThreadsList &suspended_threads,
666 void *arg) {
667 CheckForLeaksParam *param = reinterpret_cast<CheckForLeaksParam *>(arg);
668 CHECK(param)do { __sanitizer::u64 v1 = (__sanitizer::u64)((param)); __sanitizer
::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect(!!(!(v1
!= v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 668, "(" "(param)" ") " "!=" " (" "0" ")", v1, v2); } while
(false);
669 CHECK(!param->success)do { __sanitizer::u64 v1 = (__sanitizer::u64)((!param->success
)); __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 669, "(" "(!param->success)" ") " "!=" " (" "0" ")", v1,
v2); } while (false);
670 ReportUnsuspendedThreads(suspended_threads);
671 ClassifyAllChunks(suspended_threads, &param->frontier);
672 ForEachChunk(CollectLeaksCb, &param->leak_report);
673 // Clean up for subsequent leak checks. This assumes we did not overwrite any
674 // kIgnored tags.
675 ForEachChunk(ResetTagsCb, nullptr);
676 param->success = true;
677}
678
679static bool PrintResults(LeakReport &report) {
680 uptr unsuppressed_count = report.UnsuppressedLeakCount();
681 if (unsuppressed_count) {
682 Decorator d;
683 Printf(
684 "\n"
685 "================================================================="
686 "\n");
687 Printf("%s", d.Error());
688 Report("ERROR: LeakSanitizer: detected memory leaks\n");
689 Printf("%s", d.Default());
690 report.ReportTopLeaks(flags()->max_leaks);
691 }
692 if (common_flags()->print_suppressions)
693 GetSuppressionContext()->PrintMatchedSuppressions();
694 if (unsuppressed_count > 0) {
695 report.PrintSummary();
696 return true;
697 }
698 return false;
699}
700
701static bool CheckForLeaks() {
702 if (&__lsan_is_turned_off && __lsan_is_turned_off())
703 return false;
704 // Inside LockStuffAndStopTheWorld we can't run symbolizer, so we can't match
705 // suppressions. However if a stack id was previously suppressed, it should be
706 // suppressed in future checks as well.
707 for (int i = 0;; ++i) {
708 EnsureMainThreadIDIsCorrect();
709 CheckForLeaksParam param;
710 LockStuffAndStopTheWorld(CheckForLeaksCallback, &param);
711 if (!param.success) {
712 Report("LeakSanitizer has encountered a fatal error.\n");
713 Report(
714 "HINT: For debugging, try setting environment variable "
715 "LSAN_OPTIONS=verbosity=1:log_threads=1\n");
716 Report(
717 "HINT: LeakSanitizer does not work under ptrace (strace, gdb, "
718 "etc)\n");
719 Die();
720 }
721 // No new suppressions stacks, so rerun will not help and we can report.
722 if (!param.leak_report.ApplySuppressions())
723 return PrintResults(param.leak_report);
724
725 // No indirect leaks to report, so we are done here.
726 if (!param.leak_report.IndirectUnsuppressedLeakCount())
727 return PrintResults(param.leak_report);
728
729 if (i >= 8) {
730 Report("WARNING: LeakSanitizer gave up on indirect leaks suppression.\n");
731 return PrintResults(param.leak_report);
732 }
733
734 // We found a new previously unseen suppressed call stack. Rerun to make
735 // sure it does not hold indirect leaks.
736 VReport(1, "Rerun with %zu suppressed stacks.",do { if ((uptr)Verbosity() >= (1)) Report("Rerun with %zu suppressed stacks."
, GetSuppressionContext()->GetSortedSuppressedStacks().size
()); } while (0)
737 GetSuppressionContext()->GetSortedSuppressedStacks().size())do { if ((uptr)Verbosity() >= (1)) Report("Rerun with %zu suppressed stacks."
, GetSuppressionContext()->GetSortedSuppressedStacks().size
()); } while (0);
738 }
739}
740
741static bool has_reported_leaks = false;
742bool HasReportedLeaks() { return has_reported_leaks; }
743
744void DoLeakCheck() {
745 Lock l(&global_mutex);
746 static bool already_done;
747 if (already_done) return;
748 already_done = true;
749 has_reported_leaks = CheckForLeaks();
750 if (has_reported_leaks) HandleLeaks();
751}
752
753static int DoRecoverableLeakCheck() {
754 Lock l(&global_mutex);
755 bool have_leaks = CheckForLeaks();
756 return have_leaks ? 1 : 0;
757}
758
759void DoRecoverableLeakCheckVoid() { DoRecoverableLeakCheck(); }
760
761Suppression *LeakSuppressionContext::GetSuppressionForAddr(uptr addr) {
762 Suppression *s = nullptr;
763
764 // Suppress by module name.
765 if (const char *module_name
5.1
'module_name' is null
5.1
'module_name' is null
 =
6
←
Taking false branch
→
766 Symbolizer::GetOrInit()->GetModuleNameForPc(addr))
1
Calling 'Symbolizer::GetModuleNameForPc'
→
5
←
Returning from 'Symbolizer::GetModuleNameForPc'
→
767 if (context.Match(module_name, kSuppressionLeak, &s))
768 return s;
769
770 // Suppress by file or function name.
771 SymbolizedStack *frames = Symbolizer::GetOrInit()->SymbolizePC(addr);
7
←
'frames' initialized here
→
772 for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
8
←
Assuming pointer value is null
→
9
←
Loop condition is false. Execution continues on line 778
→
773 if (context.Match(cur->info.function, kSuppressionLeak, &s) ||
774 context.Match(cur->info.file, kSuppressionLeak, &s)) {
775 break;
776 }
777 }
778 frames->ClearAll();
10
←
Called C++ object pointer is null
779 return s;
780}
781
782Suppression *LeakSuppressionContext::GetSuppressionForStack(
783 u32 stack_trace_id) {
784 LazyInit();
785 StackTrace stack = StackDepotGet(stack_trace_id);
786 for (uptr i = 0; i < stack.size; i++) {
787 Suppression *s = GetSuppressionForAddr(
788 StackTrace::GetPreviousInstructionPc(stack.trace[i]));
789 if (s) {
790 suppressed_stacks_sorted = false;
791 suppressed_stacks.push_back(stack_trace_id);
792 return s;
793 }
794 }
795 return nullptr;
796}
797
798///// LeakReport implementation. /////
799
800// A hard limit on the number of distinct leaks, to avoid quadratic complexity
801// in LeakReport::AddLeakedChunk(). We don't expect to ever see this many leaks
802// in real-world applications.
803// FIXME: Get rid of this limit by changing the implementation of LeakReport to
804// use a hash table.
805const uptr kMaxLeaksConsidered = 5000;
806
807void LeakReport::AddLeakedChunk(uptr chunk, u32 stack_trace_id,
808 uptr leaked_size, ChunkTag tag) {
809 CHECK(tag == kDirectlyLeaked || tag == kIndirectlyLeaked)do { __sanitizer::u64 v1 = (__sanitizer::u64)((tag == kDirectlyLeaked
|| tag == kIndirectlyLeaked)); __sanitizer::u64 v2 = (__sanitizer
::u64)(0); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer
::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 809, "(" "(tag == kDirectlyLeaked || tag == kIndirectlyLeaked)"
") " "!=" " (" "0" ")", v1, v2); } while (false);
810 bool is_directly_leaked = (tag == kDirectlyLeaked);
811 uptr i;
812 for (i = 0; i < leaks_.size(); i++) {
813 if (leaks_[i].stack_trace_id == stack_trace_id &&
814 leaks_[i].is_directly_leaked == is_directly_leaked) {
815 leaks_[i].hit_count++;
816 leaks_[i].total_size += leaked_size;
817 break;
818 }
819 }
820 if (i == leaks_.size()) {
821 if (leaks_.size() == kMaxLeaksConsidered) return;
822 Leak leak = { next_id_++, /* hit_count */ 1, leaked_size, stack_trace_id,
823 is_directly_leaked, /* is_suppressed */ false };
824 leaks_.push_back(leak);
825 }
826 if (flags()->report_objects) {
827 LeakedObject obj = {leaks_[i].id, chunk, leaked_size};
828 leaked_objects_.push_back(obj);
829 }
830}
831
832static bool LeakComparator(const Leak &leak1, const Leak &leak2) {
833 if (leak1.is_directly_leaked == leak2.is_directly_leaked)
834 return leak1.total_size > leak2.total_size;
835 else
836 return leak1.is_directly_leaked;
837}
838
839void LeakReport::ReportTopLeaks(uptr num_leaks_to_report) {
840 CHECK(leaks_.size() <= kMaxLeaksConsidered)do { __sanitizer::u64 v1 = (__sanitizer::u64)((leaks_.size() <=
kMaxLeaksConsidered)); __sanitizer::u64 v2 = (__sanitizer::u64
)(0); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer::
CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 840, "(" "(leaks_.size() <= kMaxLeaksConsidered)" ") " "!="
" (" "0" ")", v1, v2); } while (false);
841 Printf("\n");
842 if (leaks_.size() == kMaxLeaksConsidered)
843 Printf("Too many leaks! Only the first %zu leaks encountered will be "
844 "reported.\n",
845 kMaxLeaksConsidered);
846
847 uptr unsuppressed_count = UnsuppressedLeakCount();
848 if (num_leaks_to_report > 0 && num_leaks_to_report < unsuppressed_count)
849 Printf("The %zu top leak(s):\n", num_leaks_to_report);
850 Sort(leaks_.data(), leaks_.size(), &LeakComparator);
851 uptr leaks_reported = 0;
852 for (uptr i = 0; i < leaks_.size(); i++) {
853 if (leaks_[i].is_suppressed) continue;
854 PrintReportForLeak(i);
855 leaks_reported++;
856 if (leaks_reported == num_leaks_to_report) break;
857 }
858 if (leaks_reported < unsuppressed_count) {
859 uptr remaining = unsuppressed_count - leaks_reported;
860 Printf("Omitting %zu more leak(s).\n", remaining);
861 }
862}
863
864void LeakReport::PrintReportForLeak(uptr index) {
865 Decorator d;
866 Printf("%s", d.Leak());
867 Printf("%s leak of %zu byte(s) in %zu object(s) allocated from:\n",
868 leaks_[index].is_directly_leaked ? "Direct" : "Indirect",
869 leaks_[index].total_size, leaks_[index].hit_count);
870 Printf("%s", d.Default());
871
872 PrintStackTraceById(leaks_[index].stack_trace_id);
873
874 if (flags()->report_objects) {
875 Printf("Objects leaked above:\n");
876 PrintLeakedObjectsForLeak(index);
877 Printf("\n");
878 }
879}
880
881void LeakReport::PrintLeakedObjectsForLeak(uptr index) {
882 u32 leak_id = leaks_[index].id;
883 for (uptr j = 0; j < leaked_objects_.size(); j++) {
884 if (leaked_objects_[j].leak_id == leak_id)
885 Printf("%p (%zu bytes)\n", leaked_objects_[j].addr,
886 leaked_objects_[j].size);
887 }
888}
889
890void LeakReport::PrintSummary() {
891 CHECK(leaks_.size() <= kMaxLeaksConsidered)do { __sanitizer::u64 v1 = (__sanitizer::u64)((leaks_.size() <=
kMaxLeaksConsidered)); __sanitizer::u64 v2 = (__sanitizer::u64
)(0); if (__builtin_expect(!!(!(v1 != v2)), 0)) __sanitizer::
CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 891, "(" "(leaks_.size() <= kMaxLeaksConsidered)" ") " "!="
" (" "0" ")", v1, v2); } while (false);
892 uptr bytes = 0, allocations = 0;
893 for (uptr i = 0; i < leaks_.size(); i++) {
894 if (leaks_[i].is_suppressed) continue;
895 bytes += leaks_[i].total_size;
896 allocations += leaks_[i].hit_count;
897 }
898 InternalScopedString summary;
899 summary.append("%zu byte(s) leaked in %zu allocation(s).", bytes,
900 allocations);
901 ReportErrorSummary(summary.data());
902}
903
904uptr LeakReport::ApplySuppressions() {
905 LeakSuppressionContext *suppressions = GetSuppressionContext();
906 uptr new_suppressions = false;
907 for (uptr i = 0; i < leaks_.size(); i++) {
908 Suppression *s =
909 suppressions->GetSuppressionForStack(leaks_[i].stack_trace_id);
910 if (s) {
911 s->weight += leaks_[i].total_size;
912 atomic_store_relaxed(&s->hit_count, atomic_load_relaxed(&s->hit_count) +
913 leaks_[i].hit_count);
914 leaks_[i].is_suppressed = true;
915 ++new_suppressions;
916 }
917 }
918 return new_suppressions;
919}
920
921uptr LeakReport::UnsuppressedLeakCount() {
922 uptr result = 0;
923 for (uptr i = 0; i < leaks_.size(); i++)
924 if (!leaks_[i].is_suppressed) result++;
925 return result;
926}
927
928uptr LeakReport::IndirectUnsuppressedLeakCount() {
929 uptr result = 0;
930 for (uptr i = 0; i < leaks_.size(); i++)
931 if (!leaks_[i].is_suppressed && !leaks_[i].is_directly_leaked)
932 result++;
933 return result;
934}
935
936} // namespace __lsan
937#else // CAN_SANITIZE_LEAKS
938namespace __lsan {
939void InitCommonLsan() { }
940void DoLeakCheck() { }
941void DoRecoverableLeakCheckVoid() { }
942void DisableInThisThread() { }
943void EnableInThisThread() { }
944}
945#endif // CAN_SANITIZE_LEAKS
946
947using namespace __lsan;
948
949extern "C" {
950SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
951void __lsan_ignore_object(const void *p) {
952#if CAN_SANITIZE_LEAKS1
953 if (!common_flags()->detect_leaks)
954 return;
955 // Cannot use PointsIntoChunk or LsanMetadata here, since the allocator is not
956 // locked.
957 Lock l(&global_mutex);
958 IgnoreObjectResult res = IgnoreObjectLocked(p);
959 if (res == kIgnoreObjectInvalid)
960 VReport(1, "__lsan_ignore_object(): no heap object found at %p", p)do { if ((uptr)Verbosity() >= (1)) Report("__lsan_ignore_object(): no heap object found at %p"
, p); } while (0);
961 if (res == kIgnoreObjectAlreadyIgnored)
962 VReport(1, "__lsan_ignore_object(): "do { if ((uptr)Verbosity() >= (1)) Report("__lsan_ignore_object(): "
"heap object at %p is already being ignored\n", p); } while (
0)
963 "heap object at %p is already being ignored\n", p)do { if ((uptr)Verbosity() >= (1)) Report("__lsan_ignore_object(): "
"heap object at %p is already being ignored\n", p); } while (
0);
964 if (res == kIgnoreObjectSuccess)
965 VReport(1, "__lsan_ignore_object(): ignoring heap object at %p\n", p)do { if ((uptr)Verbosity() >= (1)) Report("__lsan_ignore_object(): ignoring heap object at %p\n"
, p); } while (0);
966#endif // CAN_SANITIZE_LEAKS
967}
968
969SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
970void __lsan_register_root_region(const void *begin, uptr size) {
971#if CAN_SANITIZE_LEAKS1
972 Lock l(&global_mutex);
973 CHECK(root_regions)do { __sanitizer::u64 v1 = (__sanitizer::u64)((root_regions))
; __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 973, "(" "(root_regions)" ") " "!=" " (" "0" ")", v1, v2); }
while (false);
974 RootRegion region = {reinterpret_cast<uptr>(begin), size};
975 root_regions->push_back(region);
976 VReport(1, "Registered root region at %p of size %llu\n", begin, size)do { if ((uptr)Verbosity() >= (1)) Report("Registered root region at %p of size %llu\n"
, begin, size); } while (0);
977#endif // CAN_SANITIZE_LEAKS
978}
979
980SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
981void __lsan_unregister_root_region(const void *begin, uptr size) {
982#if CAN_SANITIZE_LEAKS1
983 Lock l(&global_mutex);
984 CHECK(root_regions)do { __sanitizer::u64 v1 = (__sanitizer::u64)((root_regions))
; __sanitizer::u64 v2 = (__sanitizer::u64)(0); if (__builtin_expect
(!!(!(v1 != v2)), 0)) __sanitizer::CheckFailed("/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/lsan_common.cpp"
, 984, "(" "(root_regions)" ") " "!=" " (" "0" ")", v1, v2); }
while (false);
985 bool removed = false;
986 for (uptr i = 0; i < root_regions->size(); i++) {
987 RootRegion region = (*root_regions)[i];
988 if (region.begin == reinterpret_cast<uptr>(begin) && region.size == size) {
989 removed = true;
990 uptr last_index = root_regions->size() - 1;
991 (*root_regions)[i] = (*root_regions)[last_index];
992 root_regions->pop_back();
993 VReport(1, "Unregistered root region at %p of size %llu\n", begin, size)do { if ((uptr)Verbosity() >= (1)) Report("Unregistered root region at %p of size %llu\n"
, begin, size); } while (0);
994 break;
995 }
996 }
997 if (!removed) {
998 Report(
999 "__lsan_unregister_root_region(): region at %p of size %llu has not "
1000 "been registered.\n",
1001 begin, size);
1002 Die();
1003 }
1004#endif // CAN_SANITIZE_LEAKS
1005}
1006
1007SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
1008void __lsan_disable() {
1009#if CAN_SANITIZE_LEAKS1
1010 __lsan::DisableInThisThread();
1011#endif
1012}
1013
1014SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
1015void __lsan_enable() {
1016#if CAN_SANITIZE_LEAKS1
1017 __lsan::EnableInThisThread();
1018#endif
1019}
1020
1021SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
1022void __lsan_do_leak_check() {
1023#if CAN_SANITIZE_LEAKS1
1024 if (common_flags()->detect_leaks)
1025 __lsan::DoLeakCheck();
1026#endif // CAN_SANITIZE_LEAKS
1027}
1028
1029SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default")))
1030int __lsan_do_recoverable_leak_check() {
1031#if CAN_SANITIZE_LEAKS1
1032 if (common_flags()->detect_leaks)
1033 return __lsan::DoRecoverableLeakCheck();
1034#endif // CAN_SANITIZE_LEAKS
1035 return 0;
1036}
1037
1038SANITIZER_INTERFACE_WEAK_DEF(const char *, __lsan_default_options, void)extern "C" __attribute__((visibility("default"))) __attribute__
((weak)) const char * __lsan_default_options(void) {
1039 return "";
1040}
1041
1042#if !SANITIZER_SUPPORTS_WEAK_HOOKS1
1043SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default"))) SANITIZER_WEAK_ATTRIBUTE__attribute__((weak))
1044int __lsan_is_turned_off() {
1045 return 0;
1046}
1047
1048SANITIZER_INTERFACE_ATTRIBUTE__attribute__((visibility("default"))) SANITIZER_WEAK_ATTRIBUTE__attribute__((weak))
1049const char *__lsan_default_suppressions() {
1050 return "";
1051}
1052#endif
1053} // extern "C"
←

/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/compiler-rt/lib/lsan/../sanitizer_common/sanitizer_symbolizer.h

1//===-- sanitizer_symbolizer.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// Symbolizer is used by sanitizers to map instruction address to a location in
10// source code at run-time. Symbolizer either uses __sanitizer_symbolize_*
11// defined in the program, or (if they are missing) tries to find and
12// launch "llvm-symbolizer" commandline tool in a separate process and
13// communicate with it.
14//
15// Generally we should try to avoid calling system library functions during
16// symbolization (and use their replacements from sanitizer_libc.h instead).
17//===----------------------------------------------------------------------===//
18#ifndef SANITIZER_SYMBOLIZER_H
19#define SANITIZER_SYMBOLIZER_H
20
21#include "sanitizer_common.h"
22#include "sanitizer_mutex.h"
23#include "sanitizer_vector.h"
24
25namespace __sanitizer {
26
27struct AddressInfo {
28 // Owns all the string members. Storage for them is
29 // (de)allocated using sanitizer internal allocator.
30 uptr address;
31
32 char *module;
33 uptr module_offset;
34 ModuleArch module_arch;
35
36 static const uptr kUnknown = ~(uptr)0;
37 char *function;
38 uptr function_offset;
39
40 char *file;
41 int line;
42 int column;
43
44 AddressInfo();
45 // Deletes all strings and resets all fields.
46 void Clear();
47 void FillModuleInfo(const char *mod_name, uptr mod_offset, ModuleArch arch);
48};
49
50// Linked list of symbolized frames (each frame is described by AddressInfo).
51struct SymbolizedStack {
52 SymbolizedStack *next;
53 AddressInfo info;
54 static SymbolizedStack *New(uptr addr);
55 // Deletes current, and all subsequent frames in the linked list.
56 // The object cannot be accessed after the call to this function.
57 void ClearAll();
58
59 private:
60 SymbolizedStack();
61};
62
63// For now, DataInfo is used to describe global variable.
64struct DataInfo {
65 // Owns all the string members. Storage for them is
66 // (de)allocated using sanitizer internal allocator.
67 char *module;
68 uptr module_offset;
69 ModuleArch module_arch;
70
71 char *file;
72 uptr line;
73 char *name;
74 uptr start;
75 uptr size;
76
77 DataInfo();
78 void Clear();
79};
80
81struct LocalInfo {
82 char *function_name = nullptr;
83 char *name = nullptr;
84 char *decl_file = nullptr;
85 unsigned decl_line = 0;
86
87 bool has_frame_offset = false;
88 bool has_size = false;
89 bool has_tag_offset = false;
90
91 sptr frame_offset;
92 uptr size;
93 uptr tag_offset;
94
95 void Clear();
96};
97
98struct FrameInfo {
99 char *module;
100 uptr module_offset;
101 ModuleArch module_arch;
102
103 InternalMmapVector<LocalInfo> locals;
104 void Clear();
105};
106
107class SymbolizerTool;
108
109class Symbolizer final {
110 public:
111 /// Initialize and return platform-specific implementation of symbolizer
112 /// (if it wasn't already initialized).
113 static Symbolizer *GetOrInit();
114 static void LateInitialize();
115 // Returns a list of symbolized frames for a given address (containing
116 // all inlined functions, if necessary).
117 SymbolizedStack *SymbolizePC(uptr address);
118 bool SymbolizeData(uptr address, DataInfo *info);
119 bool SymbolizeFrame(uptr address, FrameInfo *info);
120
121 // The module names Symbolizer returns are stable and unique for every given
122 // module. It is safe to store and compare them as pointers.
123 bool GetModuleNameAndOffsetForPC(uptr pc, const char **module_name,
124 uptr *module_address);
125 const char *GetModuleNameForPc(uptr pc) {
126 const char *module_name = nullptr;
127 uptr unused;
128 if (GetModuleNameAndOffsetForPC(pc, &module_name, &unused))
2
←
Assuming the condition is false
→
3
←
Taking false branch
→
129 return module_name;
130 return nullptr;
4
←
Returning null pointer, which participates in a condition later
→
131 }
132
133 // Release internal caches (if any).
134 void Flush();
135 // Attempts to demangle the provided C++ mangled name.
136 const char *Demangle(const char *name);
137
138 // Allow user to install hooks that would be called before/after Symbolizer
139 // does the actual file/line info fetching. Specific sanitizers may need this
140 // to distinguish system library calls made in user code from calls made
141 // during in-process symbolization.
142 typedef void (*StartSymbolizationHook)();
143 typedef void (*EndSymbolizationHook)();
144 // May be called at most once.
145 void AddHooks(StartSymbolizationHook start_hook,
146 EndSymbolizationHook end_hook);
147
148 void RefreshModules();
149 const LoadedModule *FindModuleForAddress(uptr address);
150
151 void InvalidateModuleList();
152
153 private:
154 // GetModuleNameAndOffsetForPC has to return a string to the caller.
155 // Since the corresponding module might get unloaded later, we should create
156 // our owned copies of the strings that we can safely return.
157 // ModuleNameOwner does not provide any synchronization, thus calls to
158 // its method should be protected by |mu_|.
159 class ModuleNameOwner {
160 public:
161 explicit ModuleNameOwner(Mutex *synchronized_by)
162 : last_match_(nullptr), mu_(synchronized_by) {
163 storage_.reserve(kInitialCapacity);
164 }
165 const char *GetOwnedCopy(const char *str);
166
167 private:
168 static const uptr kInitialCapacity = 1000;
169 InternalMmapVector<const char*> storage_;
170 const char *last_match_;
171
172 Mutex *mu_;
173 } module_names_;
174
175 /// Platform-specific function for creating a Symbolizer object.
176 static Symbolizer *PlatformInit();
177
178 bool FindModuleNameAndOffsetForAddress(uptr address, const char **module_name,
179 uptr *module_offset,
180 ModuleArch *module_arch);
181 ListOfModules modules_;
182 ListOfModules fallback_modules_;
183 // If stale, need to reload the modules before looking up addresses.
184 bool modules_fresh_;
185
186 // Platform-specific default demangler, must not return nullptr.
187 const char *PlatformDemangle(const char *name);
188
189 static Symbolizer *symbolizer_;
190 static StaticSpinMutex init_mu_;
191
192 // Mutex locked from public methods of |Symbolizer|, so that the internals
193 // (including individual symbolizer tools and platform-specific methods) are
194 // always synchronized.
195 Mutex mu_;
196
197 IntrusiveList<SymbolizerTool> tools_;
198
199 explicit Symbolizer(IntrusiveList<SymbolizerTool> tools);
200
201 static LowLevelAllocator symbolizer_allocator_;
202
203 StartSymbolizationHook start_hook_;
204 EndSymbolizationHook end_hook_;
205 class SymbolizerScope {
206 public:
207 explicit SymbolizerScope(const Symbolizer *sym);
208 ~SymbolizerScope();
209 private:
210 const Symbolizer *sym_;
211 };
212
213 // Calls `LateInitialize()` on all items in `tools_`.
214 void LateInitializeTools();
215};
216
217#ifdef SANITIZER_WINDOWS0
218void InitializeDbgHelpIfNeeded();
219#endif
220
221} // namespace __sanitizer
222
223#endif // SANITIZER_SYMBOLIZER_H