| //=-- lsan_common.cpp -----------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is a part of LeakSanitizer. |
| // Implementation of common leak checking functionality. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "lsan_common.h" |
| |
| #include "sanitizer_common/sanitizer_common.h" |
| #include "sanitizer_common/sanitizer_flag_parser.h" |
| #include "sanitizer_common/sanitizer_flags.h" |
| #include "sanitizer_common/sanitizer_placement_new.h" |
| #include "sanitizer_common/sanitizer_procmaps.h" |
| #include "sanitizer_common/sanitizer_report_decorator.h" |
| #include "sanitizer_common/sanitizer_stackdepot.h" |
| #include "sanitizer_common/sanitizer_stacktrace.h" |
| #include "sanitizer_common/sanitizer_suppressions.h" |
| #include "sanitizer_common/sanitizer_thread_registry.h" |
| #include "sanitizer_common/sanitizer_tls_get_addr.h" |
| |
| #if CAN_SANITIZE_LEAKS |
| namespace __lsan { |
| |
| // This mutex is used to prevent races between DoLeakCheck and IgnoreObject, and |
| // also to protect the global list of root regions. |
| Mutex global_mutex; |
| |
| Flags lsan_flags; |
| |
| |
| void DisableCounterUnderflow() { |
| if (common_flags()->detect_leaks) { |
| Report("Unmatched call to __lsan_enable().\n"); |
| Die(); |
| } |
| } |
| |
| void Flags::SetDefaults() { |
| #define LSAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue; |
| #include "lsan_flags.inc" |
| #undef LSAN_FLAG |
| } |
| |
| void RegisterLsanFlags(FlagParser *parser, Flags *f) { |
| #define LSAN_FLAG(Type, Name, DefaultValue, Description) \ |
| RegisterFlag(parser, #Name, Description, &f->Name); |
| #include "lsan_flags.inc" |
| #undef LSAN_FLAG |
| } |
| |
| #define LOG_POINTERS(...) \ |
| do { \ |
| if (flags()->log_pointers) Report(__VA_ARGS__); \ |
| } while (0) |
| |
| #define LOG_THREADS(...) \ |
| do { \ |
| if (flags()->log_threads) Report(__VA_ARGS__); \ |
| } while (0) |
| |
| class LeakSuppressionContext { |
| bool parsed = false; |
| SuppressionContext context; |
| bool suppressed_stacks_sorted = true; |
| InternalMmapVector<u32> suppressed_stacks; |
| |
| Suppression *GetSuppressionForAddr(uptr addr); |
| void LazyInit(); |
| |
| public: |
| LeakSuppressionContext(const char *supprression_types[], |
| int suppression_types_num) |
| : context(supprression_types, suppression_types_num) {} |
| |
| Suppression *GetSuppressionForStack(u32 stack_trace_id, |
| const StackTrace &stack); |
| |
| const InternalMmapVector<u32> &GetSortedSuppressedStacks() { |
| if (!suppressed_stacks_sorted) { |
| suppressed_stacks_sorted = true; |
| SortAndDedup(suppressed_stacks); |
| } |
| return suppressed_stacks; |
| } |
| void PrintMatchedSuppressions(); |
| }; |
| |
| ALIGNED(64) static char suppression_placeholder[sizeof(LeakSuppressionContext)]; |
| static LeakSuppressionContext *suppression_ctx = nullptr; |
| static const char kSuppressionLeak[] = "leak"; |
| static const char *kSuppressionTypes[] = { kSuppressionLeak }; |
| static const char kStdSuppressions[] = |
| #if SANITIZER_SUPPRESS_LEAK_ON_PTHREAD_EXIT |
| // For more details refer to the SANITIZER_SUPPRESS_LEAK_ON_PTHREAD_EXIT |
| // definition. |
| "leak:*pthread_exit*\n" |
| #endif // SANITIZER_SUPPRESS_LEAK_ON_PTHREAD_EXIT |
| #if SANITIZER_MAC |
| // For Darwin and os_log/os_trace: https://reviews.llvm.org/D35173 |
| "leak:*_os_trace*\n" |
| #endif |
| // TLS leak in some glibc versions, described in |
| // https://sourceware.org/bugzilla/show_bug.cgi?id=12650. |
| "leak:*tls_get_addr*\n"; |
| |
| void InitializeSuppressions() { |
| CHECK_EQ(nullptr, suppression_ctx); |
| suppression_ctx = new (suppression_placeholder) |
| LeakSuppressionContext(kSuppressionTypes, ARRAY_SIZE(kSuppressionTypes)); |
| } |
| |
| void LeakSuppressionContext::LazyInit() { |
| if (!parsed) { |
| parsed = true; |
| context.ParseFromFile(flags()->suppressions); |
| if (&__lsan_default_suppressions) |
| context.Parse(__lsan_default_suppressions()); |
| context.Parse(kStdSuppressions); |
| } |
| } |
| |
| static LeakSuppressionContext *GetSuppressionContext() { |
| CHECK(suppression_ctx); |
| return suppression_ctx; |
| } |
| |
| static InternalMmapVectorNoCtor<RootRegion> root_regions; |
| |
| InternalMmapVectorNoCtor<RootRegion> const *GetRootRegions() { |
| return &root_regions; |
| } |
| |
| void InitCommonLsan() { |
| if (common_flags()->detect_leaks) { |
| // Initialization which can fail or print warnings should only be done if |
| // LSan is actually enabled. |
| InitializeSuppressions(); |
| InitializePlatformSpecificModules(); |
| } |
| } |
| |
| class Decorator: public __sanitizer::SanitizerCommonDecorator { |
| public: |
| Decorator() : SanitizerCommonDecorator() { } |
| const char *Error() { return Red(); } |
| const char *Leak() { return Blue(); } |
| }; |
| |
| static inline bool CanBeAHeapPointer(uptr p) { |
| // Since our heap is located in mmap-ed memory, we can assume a sensible lower |
| // bound on heap addresses. |
| const uptr kMinAddress = 4 * 4096; |
| if (p < kMinAddress) return false; |
| #if defined(__x86_64__) |
| // Accept only canonical form user-space addresses. |
| return ((p >> 47) == 0); |
| #elif defined(__mips64) |
| return ((p >> 40) == 0); |
| #elif defined(__aarch64__) |
| unsigned runtimeVMA = |
| (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1); |
| return ((p >> runtimeVMA) == 0); |
| #else |
| return true; |
| #endif |
| } |
| |
| // Scans the memory range, looking for byte patterns that point into allocator |
| // chunks. Marks those chunks with |tag| and adds them to |frontier|. |
| // There are two usage modes for this function: finding reachable chunks |
| // (|tag| = kReachable) and finding indirectly leaked chunks |
| // (|tag| = kIndirectlyLeaked). In the second case, there's no flood fill, |
| // so |frontier| = 0. |
| void ScanRangeForPointers(uptr begin, uptr end, |
| Frontier *frontier, |
| const char *region_type, ChunkTag tag) { |
| CHECK(tag == kReachable || tag == kIndirectlyLeaked); |
| const uptr alignment = flags()->pointer_alignment(); |
| LOG_POINTERS("Scanning %s range %p-%p.\n", region_type, (void *)begin, |
| (void *)end); |
| uptr pp = begin; |
| if (pp % alignment) |
| pp = pp + alignment - pp % alignment; |
| for (; pp + sizeof(void *) <= end; pp += alignment) { |
| void *p = *reinterpret_cast<void **>(pp); |
| if (!CanBeAHeapPointer(reinterpret_cast<uptr>(p))) continue; |
| uptr chunk = PointsIntoChunk(p); |
| if (!chunk) continue; |
| // Pointers to self don't count. This matters when tag == kIndirectlyLeaked. |
| if (chunk == begin) continue; |
| LsanMetadata m(chunk); |
| if (m.tag() == kReachable || m.tag() == kIgnored) continue; |
| |
| // Do this check relatively late so we can log only the interesting cases. |
| if (!flags()->use_poisoned && WordIsPoisoned(pp)) { |
| LOG_POINTERS( |
| "%p is poisoned: ignoring %p pointing into chunk %p-%p of size " |
| "%zu.\n", |
| (void *)pp, p, (void *)chunk, (void *)(chunk + m.requested_size()), |
| m.requested_size()); |
| continue; |
| } |
| |
| m.set_tag(tag); |
| LOG_POINTERS("%p: found %p pointing into chunk %p-%p of size %zu.\n", |
| (void *)pp, p, (void *)chunk, |
| (void *)(chunk + m.requested_size()), m.requested_size()); |
| if (frontier) |
| frontier->push_back(chunk); |
| } |
| } |
| |
| // Scans a global range for pointers |
| void ScanGlobalRange(uptr begin, uptr end, Frontier *frontier) { |
| uptr allocator_begin = 0, allocator_end = 0; |
| GetAllocatorGlobalRange(&allocator_begin, &allocator_end); |
| if (begin <= allocator_begin && allocator_begin < end) { |
| CHECK_LE(allocator_begin, allocator_end); |
| CHECK_LE(allocator_end, end); |
| if (begin < allocator_begin) |
| ScanRangeForPointers(begin, allocator_begin, frontier, "GLOBAL", |
| kReachable); |
| if (allocator_end < end) |
| ScanRangeForPointers(allocator_end, end, frontier, "GLOBAL", kReachable); |
| } else { |
| ScanRangeForPointers(begin, end, frontier, "GLOBAL", kReachable); |
| } |
| } |
| |
| void ForEachExtraStackRangeCb(uptr begin, uptr end, void* arg) { |
| Frontier *frontier = reinterpret_cast<Frontier *>(arg); |
| ScanRangeForPointers(begin, end, frontier, "FAKE STACK", kReachable); |
| } |
| |
| #if SANITIZER_FUCHSIA |
| |
| // Fuchsia handles all threads together with its own callback. |
| static void ProcessThreads(SuspendedThreadsList const &, Frontier *) {} |
| |
| #else |
| |
| #if SANITIZER_ANDROID |
| // FIXME: Move this out into *libcdep.cpp |
| extern "C" SANITIZER_WEAK_ATTRIBUTE void __libc_iterate_dynamic_tls( |
| pid_t, void (*cb)(void *, void *, uptr, void *), void *); |
| #endif |
| |
| static void ProcessThreadRegistry(Frontier *frontier) { |
| InternalMmapVector<uptr> ptrs; |
| GetThreadRegistryLocked()->RunCallbackForEachThreadLocked( |
| GetAdditionalThreadContextPtrs, &ptrs); |
| |
| for (uptr i = 0; i < ptrs.size(); ++i) { |
| void *ptr = reinterpret_cast<void *>(ptrs[i]); |
| uptr chunk = PointsIntoChunk(ptr); |
| if (!chunk) |
| continue; |
| LsanMetadata m(chunk); |
| if (!m.allocated()) |
| continue; |
| |
| // Mark as reachable and add to frontier. |
| LOG_POINTERS("Treating pointer %p from ThreadContext as reachable\n", ptr); |
| m.set_tag(kReachable); |
| frontier->push_back(chunk); |
| } |
| } |
| |
| // Scans thread data (stacks and TLS) for heap pointers. |
| static void ProcessThreads(SuspendedThreadsList const &suspended_threads, |
| Frontier *frontier) { |
| InternalMmapVector<uptr> registers; |
| for (uptr i = 0; i < suspended_threads.ThreadCount(); i++) { |
| tid_t os_id = static_cast<tid_t>(suspended_threads.GetThreadID(i)); |
| LOG_THREADS("Processing thread %llu.\n", os_id); |
| uptr stack_begin, stack_end, tls_begin, tls_end, cache_begin, cache_end; |
| DTLS *dtls; |
| bool thread_found = GetThreadRangesLocked(os_id, &stack_begin, &stack_end, |
| &tls_begin, &tls_end, |
| &cache_begin, &cache_end, &dtls); |
| if (!thread_found) { |
| // If a thread can't be found in the thread registry, it's probably in the |
| // process of destruction. Log this event and move on. |
| LOG_THREADS("Thread %llu not found in registry.\n", os_id); |
| continue; |
| } |
| uptr sp; |
| PtraceRegistersStatus have_registers = |
| suspended_threads.GetRegistersAndSP(i, ®isters, &sp); |
| if (have_registers != REGISTERS_AVAILABLE) { |
| Report("Unable to get registers from thread %llu.\n", os_id); |
| // If unable to get SP, consider the entire stack to be reachable unless |
| // GetRegistersAndSP failed with ESRCH. |
| if (have_registers == REGISTERS_UNAVAILABLE_FATAL) continue; |
| sp = stack_begin; |
| } |
| |
| if (flags()->use_registers && have_registers) { |
| uptr registers_begin = reinterpret_cast<uptr>(registers.data()); |
| uptr registers_end = |
| reinterpret_cast<uptr>(registers.data() + registers.size()); |
| ScanRangeForPointers(registers_begin, registers_end, frontier, |
| "REGISTERS", kReachable); |
| } |
| |
| if (flags()->use_stacks) { |
| LOG_THREADS("Stack at %p-%p (SP = %p).\n", (void *)stack_begin, |
| (void *)stack_end, (void *)sp); |
| if (sp < stack_begin || sp >= stack_end) { |
| // SP is outside the recorded stack range (e.g. the thread is running a |
| // signal handler on alternate stack, or swapcontext was used). |
| // Again, consider the entire stack range to be reachable. |
| LOG_THREADS("WARNING: stack pointer not in stack range.\n"); |
| uptr page_size = GetPageSizeCached(); |
| int skipped = 0; |
| while (stack_begin < stack_end && |
| !IsAccessibleMemoryRange(stack_begin, 1)) { |
| skipped++; |
| stack_begin += page_size; |
| } |
| LOG_THREADS("Skipped %d guard page(s) to obtain stack %p-%p.\n", |
| skipped, (void *)stack_begin, (void *)stack_end); |
| } else { |
| // Shrink the stack range to ignore out-of-scope values. |
| stack_begin = sp; |
| } |
| ScanRangeForPointers(stack_begin, stack_end, frontier, "STACK", |
| kReachable); |
| ForEachExtraStackRange(os_id, ForEachExtraStackRangeCb, frontier); |
| } |
| |
| if (flags()->use_tls) { |
| if (tls_begin) { |
| LOG_THREADS("TLS at %p-%p.\n", (void *)tls_begin, (void *)tls_end); |
| // If the tls and cache ranges don't overlap, scan full tls range, |
| // otherwise, only scan the non-overlapping portions |
| if (cache_begin == cache_end || tls_end < cache_begin || |
| tls_begin > cache_end) { |
| ScanRangeForPointers(tls_begin, tls_end, frontier, "TLS", kReachable); |
| } else { |
| if (tls_begin < cache_begin) |
| ScanRangeForPointers(tls_begin, cache_begin, frontier, "TLS", |
| kReachable); |
| if (tls_end > cache_end) |
| ScanRangeForPointers(cache_end, tls_end, frontier, "TLS", |
| kReachable); |
| } |
| } |
| #if SANITIZER_ANDROID |
| auto *cb = +[](void *dtls_begin, void *dtls_end, uptr /*dso_idd*/, |
| void *arg) -> void { |
| ScanRangeForPointers(reinterpret_cast<uptr>(dtls_begin), |
| reinterpret_cast<uptr>(dtls_end), |
| reinterpret_cast<Frontier *>(arg), "DTLS", |
| kReachable); |
| }; |
| |
| // FIXME: There might be a race-condition here (and in Bionic) if the |
| // thread is suspended in the middle of updating its DTLS. IOWs, we |
| // could scan already freed memory. (probably fine for now) |
| __libc_iterate_dynamic_tls(os_id, cb, frontier); |
| #else |
| if (dtls && !DTLSInDestruction(dtls)) { |
| ForEachDVT(dtls, [&](const DTLS::DTV &dtv, int id) { |
| uptr dtls_beg = dtv.beg; |
| uptr dtls_end = dtls_beg + dtv.size; |
| if (dtls_beg < dtls_end) { |
| LOG_THREADS("DTLS %d at %p-%p.\n", id, (void *)dtls_beg, |
| (void *)dtls_end); |
| ScanRangeForPointers(dtls_beg, dtls_end, frontier, "DTLS", |
| kReachable); |
| } |
| }); |
| } else { |
| // We are handling a thread with DTLS under destruction. Log about |
| // this and continue. |
| LOG_THREADS("Thread %llu has DTLS under destruction.\n", os_id); |
| } |
| #endif |
| } |
| } |
| |
| // Add pointers reachable from ThreadContexts |
| ProcessThreadRegistry(frontier); |
| } |
| |
| #endif // SANITIZER_FUCHSIA |
| |
| void ScanRootRegion(Frontier *frontier, const RootRegion &root_region, |
| uptr region_begin, uptr region_end, bool is_readable) { |
| uptr intersection_begin = Max(root_region.begin, region_begin); |
| uptr intersection_end = Min(region_end, root_region.begin + root_region.size); |
| if (intersection_begin >= intersection_end) return; |
| LOG_POINTERS("Root region %p-%p intersects with mapped region %p-%p (%s)\n", |
| (void *)root_region.begin, |
| (void *)(root_region.begin + root_region.size), |
| (void *)region_begin, (void *)region_end, |
| is_readable ? "readable" : "unreadable"); |
| if (is_readable) |
| ScanRangeForPointers(intersection_begin, intersection_end, frontier, "ROOT", |
| kReachable); |
| } |
| |
| static void ProcessRootRegion(Frontier *frontier, |
| const RootRegion &root_region) { |
| MemoryMappingLayout proc_maps(/*cache_enabled*/ true); |
| MemoryMappedSegment segment; |
| while (proc_maps.Next(&segment)) { |
| ScanRootRegion(frontier, root_region, segment.start, segment.end, |
| segment.IsReadable()); |
| } |
| } |
| |
| // Scans root regions for heap pointers. |
| static void ProcessRootRegions(Frontier *frontier) { |
| if (!flags()->use_root_regions) return; |
| for (uptr i = 0; i < root_regions.size(); i++) |
| ProcessRootRegion(frontier, root_regions[i]); |
| } |
| |
| static void FloodFillTag(Frontier *frontier, ChunkTag tag) { |
| while (frontier->size()) { |
| uptr next_chunk = frontier->back(); |
| frontier->pop_back(); |
| LsanMetadata m(next_chunk); |
| ScanRangeForPointers(next_chunk, next_chunk + m.requested_size(), frontier, |
| "HEAP", tag); |
| } |
| } |
| |
| // ForEachChunk callback. If the chunk is marked as leaked, marks all chunks |
| // which are reachable from it as indirectly leaked. |
| static void MarkIndirectlyLeakedCb(uptr chunk, void *arg) { |
| chunk = GetUserBegin(chunk); |
| LsanMetadata m(chunk); |
| if (m.allocated() && m.tag() != kReachable) { |
| ScanRangeForPointers(chunk, chunk + m.requested_size(), |
| /* frontier */ nullptr, "HEAP", kIndirectlyLeaked); |
| } |
| } |
| |
| static void IgnoredSuppressedCb(uptr chunk, void *arg) { |
| CHECK(arg); |
| chunk = GetUserBegin(chunk); |
| LsanMetadata m(chunk); |
| if (!m.allocated() || m.tag() == kIgnored) |
| return; |
| |
| const InternalMmapVector<u32> &suppressed = |
| *static_cast<const InternalMmapVector<u32> *>(arg); |
| uptr idx = InternalLowerBound(suppressed, m.stack_trace_id()); |
| if (idx >= suppressed.size() || m.stack_trace_id() != suppressed[idx]) |
| return; |
| |
| LOG_POINTERS("Suppressed: chunk %p-%p of size %zu.\n", (void *)chunk, |
| (void *)(chunk + m.requested_size()), m.requested_size()); |
| m.set_tag(kIgnored); |
| } |
| |
| // ForEachChunk callback. If chunk is marked as ignored, adds its address to |
| // frontier. |
| static void CollectIgnoredCb(uptr chunk, void *arg) { |
| CHECK(arg); |
| chunk = GetUserBegin(chunk); |
| LsanMetadata m(chunk); |
| if (m.allocated() && m.tag() == kIgnored) { |
| LOG_POINTERS("Ignored: chunk %p-%p of size %zu.\n", (void *)chunk, |
| (void *)(chunk + m.requested_size()), m.requested_size()); |
| reinterpret_cast<Frontier *>(arg)->push_back(chunk); |
| } |
| } |
| |
| static uptr GetCallerPC(const StackTrace &stack) { |
| // The top frame is our malloc/calloc/etc. The next frame is the caller. |
| if (stack.size >= 2) |
| return stack.trace[1]; |
| return 0; |
| } |
| |
| struct InvalidPCParam { |
| Frontier *frontier; |
| bool skip_linker_allocations; |
| }; |
| |
| // ForEachChunk callback. If the caller pc is invalid or is within the linker, |
| // mark as reachable. Called by ProcessPlatformSpecificAllocations. |
| static void MarkInvalidPCCb(uptr chunk, void *arg) { |
| CHECK(arg); |
| InvalidPCParam *param = reinterpret_cast<InvalidPCParam *>(arg); |
| chunk = GetUserBegin(chunk); |
| LsanMetadata m(chunk); |
| if (m.allocated() && m.tag() != kReachable && m.tag() != kIgnored) { |
| u32 stack_id = m.stack_trace_id(); |
| uptr caller_pc = 0; |
| if (stack_id > 0) |
| caller_pc = GetCallerPC(StackDepotGet(stack_id)); |
| // If caller_pc is unknown, this chunk may be allocated in a coroutine. Mark |
| // it as reachable, as we can't properly report its allocation stack anyway. |
| if (caller_pc == 0 || (param->skip_linker_allocations && |
| GetLinker()->containsAddress(caller_pc))) { |
| m.set_tag(kReachable); |
| param->frontier->push_back(chunk); |
| } |
| } |
| } |
| |
| // On Linux, treats all chunks allocated from ld-linux.so as reachable, which |
| // covers dynamically allocated TLS blocks, internal dynamic loader's loaded |
| // modules accounting etc. |
| // Dynamic TLS blocks contain the TLS variables of dynamically loaded modules. |
| // They are allocated with a __libc_memalign() call in allocate_and_init() |
| // (elf/dl-tls.c). Glibc won't tell us the address ranges occupied by those |
| // blocks, but we can make sure they come from our own allocator by intercepting |
| // __libc_memalign(). On top of that, there is no easy way to reach them. Their |
| // addresses are stored in a dynamically allocated array (the DTV) which is |
| // referenced from the static TLS. Unfortunately, we can't just rely on the DTV |
| // being reachable from the static TLS, and the dynamic TLS being reachable from |
| // the DTV. This is because the initial DTV is allocated before our interception |
| // mechanism kicks in, and thus we don't recognize it as allocated memory. We |
| // can't special-case it either, since we don't know its size. |
| // Our solution is to include in the root set all allocations made from |
| // ld-linux.so (which is where allocate_and_init() is implemented). This is |
| // guaranteed to include all dynamic TLS blocks (and possibly other allocations |
| // which we don't care about). |
| // On all other platforms, this simply checks to ensure that the caller pc is |
| // valid before reporting chunks as leaked. |
| static void ProcessPC(Frontier *frontier) { |
| InvalidPCParam arg; |
| arg.frontier = frontier; |
| arg.skip_linker_allocations = |
| flags()->use_tls && flags()->use_ld_allocations && GetLinker() != nullptr; |
| ForEachChunk(MarkInvalidPCCb, &arg); |
| } |
| |
| // Sets the appropriate tag on each chunk. |
| static void ClassifyAllChunks(SuspendedThreadsList const &suspended_threads, |
| Frontier *frontier) { |
| const InternalMmapVector<u32> &suppressed_stacks = |
| GetSuppressionContext()->GetSortedSuppressedStacks(); |
| if (!suppressed_stacks.empty()) { |
| ForEachChunk(IgnoredSuppressedCb, |
| const_cast<InternalMmapVector<u32> *>(&suppressed_stacks)); |
| } |
| ForEachChunk(CollectIgnoredCb, frontier); |
| ProcessGlobalRegions(frontier); |
| ProcessThreads(suspended_threads, frontier); |
| ProcessRootRegions(frontier); |
| FloodFillTag(frontier, kReachable); |
| |
| CHECK_EQ(0, frontier->size()); |
| ProcessPC(frontier); |
| |
| // The check here is relatively expensive, so we do this in a separate flood |
| // fill. That way we can skip the check for chunks that are reachable |
| // otherwise. |
| LOG_POINTERS("Processing platform-specific allocations.\n"); |
| ProcessPlatformSpecificAllocations(frontier); |
| FloodFillTag(frontier, kReachable); |
| |
| // Iterate over leaked chunks and mark those that are reachable from other |
| // leaked chunks. |
| LOG_POINTERS("Scanning leaked chunks.\n"); |
| ForEachChunk(MarkIndirectlyLeakedCb, nullptr); |
| } |
| |
| // ForEachChunk callback. Resets the tags to pre-leak-check state. |
| static void ResetTagsCb(uptr chunk, void *arg) { |
| (void)arg; |
| chunk = GetUserBegin(chunk); |
| LsanMetadata m(chunk); |
| if (m.allocated() && m.tag() != kIgnored) |
| m.set_tag(kDirectlyLeaked); |
| } |
| |
| // ForEachChunk callback. Aggregates information about unreachable chunks into |
| // a LeakReport. |
| static void CollectLeaksCb(uptr chunk, void *arg) { |
| CHECK(arg); |
| LeakReport *leak_report = reinterpret_cast<LeakReport *>(arg); |
| chunk = GetUserBegin(chunk); |
| LsanMetadata m(chunk); |
| if (!m.allocated()) return; |
| if (m.tag() == kDirectlyLeaked || m.tag() == kIndirectlyLeaked) { |
| leak_report->AddLeakedChunk(chunk, m.stack_trace_id(), m.requested_size(), |
| m.tag()); |
| } |
| } |
| |
| void LeakSuppressionContext::PrintMatchedSuppressions() { |
| InternalMmapVector<Suppression *> matched; |
| context.GetMatched(&matched); |
| if (!matched.size()) |
| return; |
| const char *line = "-----------------------------------------------------"; |
| Printf("%s\n", line); |
| Printf("Suppressions used:\n"); |
| Printf(" count bytes template\n"); |
| for (uptr i = 0; i < matched.size(); i++) { |
| Printf("%7zu %10zu %s\n", |
| static_cast<uptr>(atomic_load_relaxed(&matched[i]->hit_count)), |
| matched[i]->weight, matched[i]->templ); |
| } |
| Printf("%s\n\n", line); |
| } |
| |
| static void ReportIfNotSuspended(ThreadContextBase *tctx, void *arg) { |
| const InternalMmapVector<tid_t> &suspended_threads = |
| *(const InternalMmapVector<tid_t> *)arg; |
| if (tctx->status == ThreadStatusRunning) { |
| uptr i = InternalLowerBound(suspended_threads, tctx->os_id); |
| if (i >= suspended_threads.size() || suspended_threads[i] != tctx->os_id) |
| Report( |
| "Running thread %llu was not suspended. False leaks are possible.\n", |
| tctx->os_id); |
| } |
| } |
| |
| #if SANITIZER_FUCHSIA |
| |
| // Fuchsia provides a libc interface that guarantees all threads are |
| // covered, and SuspendedThreadList is never really used. |
| static void ReportUnsuspendedThreads(const SuspendedThreadsList &) {} |
| |
| #else // !SANITIZER_FUCHSIA |
| |
| static void ReportUnsuspendedThreads( |
| const SuspendedThreadsList &suspended_threads) { |
| InternalMmapVector<tid_t> threads(suspended_threads.ThreadCount()); |
| for (uptr i = 0; i < suspended_threads.ThreadCount(); ++i) |
| threads[i] = suspended_threads.GetThreadID(i); |
| |
| Sort(threads.data(), threads.size()); |
| |
| GetThreadRegistryLocked()->RunCallbackForEachThreadLocked( |
| &ReportIfNotSuspended, &threads); |
| } |
| |
| #endif // !SANITIZER_FUCHSIA |
| |
| static void CheckForLeaksCallback(const SuspendedThreadsList &suspended_threads, |
| void *arg) { |
| CheckForLeaksParam *param = reinterpret_cast<CheckForLeaksParam *>(arg); |
| CHECK(param); |
| CHECK(!param->success); |
| ReportUnsuspendedThreads(suspended_threads); |
| ClassifyAllChunks(suspended_threads, ¶m->frontier); |
| ForEachChunk(CollectLeaksCb, ¶m->leak_report); |
| // Clean up for subsequent leak checks. This assumes we did not overwrite any |
| // kIgnored tags. |
| ForEachChunk(ResetTagsCb, nullptr); |
| param->success = true; |
| } |
| |
| static bool PrintResults(LeakReport &report) { |
| uptr unsuppressed_count = report.UnsuppressedLeakCount(); |
| if (unsuppressed_count) { |
| Decorator d; |
| Printf( |
| "\n" |
| "=================================================================" |
| "\n"); |
| Printf("%s", d.Error()); |
| Report("ERROR: LeakSanitizer: detected memory leaks\n"); |
| Printf("%s", d.Default()); |
| report.ReportTopLeaks(flags()->max_leaks); |
| } |
| if (common_flags()->print_suppressions) |
| GetSuppressionContext()->PrintMatchedSuppressions(); |
| if (unsuppressed_count > 0) { |
| report.PrintSummary(); |
| return true; |
| } |
| return false; |
| } |
| |
| static bool CheckForLeaks() { |
| if (&__lsan_is_turned_off && __lsan_is_turned_off()) |
| return false; |
| // Inside LockStuffAndStopTheWorld we can't run symbolizer, so we can't match |
| // suppressions. However if a stack id was previously suppressed, it should be |
| // suppressed in future checks as well. |
| for (int i = 0;; ++i) { |
| EnsureMainThreadIDIsCorrect(); |
| CheckForLeaksParam param; |
| LockStuffAndStopTheWorld(CheckForLeaksCallback, ¶m); |
| if (!param.success) { |
| Report("LeakSanitizer has encountered a fatal error.\n"); |
| Report( |
| "HINT: For debugging, try setting environment variable " |
| "LSAN_OPTIONS=verbosity=1:log_threads=1\n"); |
| Report( |
| "HINT: LeakSanitizer does not work under ptrace (strace, gdb, " |
| "etc)\n"); |
| Die(); |
| } |
| // No new suppressions stacks, so rerun will not help and we can report. |
| if (!param.leak_report.ApplySuppressions()) |
| return PrintResults(param.leak_report); |
| |
| // No indirect leaks to report, so we are done here. |
| if (!param.leak_report.IndirectUnsuppressedLeakCount()) |
| return PrintResults(param.leak_report); |
| |
| if (i >= 8) { |
| Report("WARNING: LeakSanitizer gave up on indirect leaks suppression.\n"); |
| return PrintResults(param.leak_report); |
| } |
| |
| // We found a new previously unseen suppressed call stack. Rerun to make |
| // sure it does not hold indirect leaks. |
| VReport(1, "Rerun with %zu suppressed stacks.", |
| GetSuppressionContext()->GetSortedSuppressedStacks().size()); |
| } |
| } |
| |
| static bool has_reported_leaks = false; |
| bool HasReportedLeaks() { return has_reported_leaks; } |
| |
| void DoLeakCheck() { |
| Lock l(&global_mutex); |
| static bool already_done; |
| if (already_done) return; |
| already_done = true; |
| has_reported_leaks = CheckForLeaks(); |
| if (has_reported_leaks) HandleLeaks(); |
| } |
| |
| static int DoRecoverableLeakCheck() { |
| Lock l(&global_mutex); |
| bool have_leaks = CheckForLeaks(); |
| return have_leaks ? 1 : 0; |
| } |
| |
| void DoRecoverableLeakCheckVoid() { DoRecoverableLeakCheck(); } |
| |
| Suppression *LeakSuppressionContext::GetSuppressionForAddr(uptr addr) { |
| Suppression *s = nullptr; |
| |
| // Suppress by module name. |
| if (const char *module_name = |
| Symbolizer::GetOrInit()->GetModuleNameForPc(addr)) |
| if (context.Match(module_name, kSuppressionLeak, &s)) |
| return s; |
| |
| // Suppress by file or function name. |
| SymbolizedStack *frames = Symbolizer::GetOrInit()->SymbolizePC(addr); |
| for (SymbolizedStack *cur = frames; cur; cur = cur->next) { |
| if (context.Match(cur->info.function, kSuppressionLeak, &s) || |
| context.Match(cur->info.file, kSuppressionLeak, &s)) { |
| break; |
| } |
| } |
| frames->ClearAll(); |
| return s; |
| } |
| |
| Suppression *LeakSuppressionContext::GetSuppressionForStack( |
| u32 stack_trace_id, const StackTrace &stack) { |
| LazyInit(); |
| for (uptr i = 0; i < stack.size; i++) { |
| Suppression *s = GetSuppressionForAddr( |
| StackTrace::GetPreviousInstructionPc(stack.trace[i])); |
| if (s) { |
| suppressed_stacks_sorted = false; |
| suppressed_stacks.push_back(stack_trace_id); |
| return s; |
| } |
| } |
| return nullptr; |
| } |
| |
| ///// LeakReport implementation. ///// |
| |
| // A hard limit on the number of distinct leaks, to avoid quadratic complexity |
| // in LeakReport::AddLeakedChunk(). We don't expect to ever see this many leaks |
| // in real-world applications. |
| // FIXME: Get rid of this limit by changing the implementation of LeakReport to |
| // use a hash table. |
| const uptr kMaxLeaksConsidered = 5000; |
| |
| void LeakReport::AddLeakedChunk(uptr chunk, u32 stack_trace_id, |
| uptr leaked_size, ChunkTag tag) { |
| CHECK(tag == kDirectlyLeaked || tag == kIndirectlyLeaked); |
| |
| if (u32 resolution = flags()->resolution) { |
| StackTrace stack = StackDepotGet(stack_trace_id); |
| stack.size = Min(stack.size, resolution); |
| stack_trace_id = StackDepotPut(stack); |
| } |
| |
| bool is_directly_leaked = (tag == kDirectlyLeaked); |
| uptr i; |
| for (i = 0; i < leaks_.size(); i++) { |
| if (leaks_[i].stack_trace_id == stack_trace_id && |
| leaks_[i].is_directly_leaked == is_directly_leaked) { |
| leaks_[i].hit_count++; |
| leaks_[i].total_size += leaked_size; |
| break; |
| } |
| } |
| if (i == leaks_.size()) { |
| if (leaks_.size() == kMaxLeaksConsidered) return; |
| Leak leak = { next_id_++, /* hit_count */ 1, leaked_size, stack_trace_id, |
| is_directly_leaked, /* is_suppressed */ false }; |
| leaks_.push_back(leak); |
| } |
| if (flags()->report_objects) { |
| LeakedObject obj = {leaks_[i].id, chunk, leaked_size}; |
| leaked_objects_.push_back(obj); |
| } |
| } |
| |
| static bool LeakComparator(const Leak &leak1, const Leak &leak2) { |
| if (leak1.is_directly_leaked == leak2.is_directly_leaked) |
| return leak1.total_size > leak2.total_size; |
| else |
| return leak1.is_directly_leaked; |
| } |
| |
| void LeakReport::ReportTopLeaks(uptr num_leaks_to_report) { |
| CHECK(leaks_.size() <= kMaxLeaksConsidered); |
| Printf("\n"); |
| if (leaks_.size() == kMaxLeaksConsidered) |
| Printf("Too many leaks! Only the first %zu leaks encountered will be " |
| "reported.\n", |
| kMaxLeaksConsidered); |
| |
| uptr unsuppressed_count = UnsuppressedLeakCount(); |
| if (num_leaks_to_report > 0 && num_leaks_to_report < unsuppressed_count) |
| Printf("The %zu top leak(s):\n", num_leaks_to_report); |
| Sort(leaks_.data(), leaks_.size(), &LeakComparator); |
| uptr leaks_reported = 0; |
| for (uptr i = 0; i < leaks_.size(); i++) { |
| if (leaks_[i].is_suppressed) continue; |
| PrintReportForLeak(i); |
| leaks_reported++; |
| if (leaks_reported == num_leaks_to_report) break; |
| } |
| if (leaks_reported < unsuppressed_count) { |
| uptr remaining = unsuppressed_count - leaks_reported; |
| Printf("Omitting %zu more leak(s).\n", remaining); |
| } |
| } |
| |
| void LeakReport::PrintReportForLeak(uptr index) { |
| Decorator d; |
| Printf("%s", d.Leak()); |
| Printf("%s leak of %zu byte(s) in %zu object(s) allocated from:\n", |
| leaks_[index].is_directly_leaked ? "Direct" : "Indirect", |
| leaks_[index].total_size, leaks_[index].hit_count); |
| Printf("%s", d.Default()); |
| |
| CHECK(leaks_[index].stack_trace_id); |
| StackDepotGet(leaks_[index].stack_trace_id).Print(); |
| |
| if (flags()->report_objects) { |
| Printf("Objects leaked above:\n"); |
| PrintLeakedObjectsForLeak(index); |
| Printf("\n"); |
| } |
| } |
| |
| void LeakReport::PrintLeakedObjectsForLeak(uptr index) { |
| u32 leak_id = leaks_[index].id; |
| for (uptr j = 0; j < leaked_objects_.size(); j++) { |
| if (leaked_objects_[j].leak_id == leak_id) |
| Printf("%p (%zu bytes)\n", (void *)leaked_objects_[j].addr, |
| leaked_objects_[j].size); |
| } |
| } |
| |
| void LeakReport::PrintSummary() { |
| CHECK(leaks_.size() <= kMaxLeaksConsidered); |
| uptr bytes = 0, allocations = 0; |
| for (uptr i = 0; i < leaks_.size(); i++) { |
| if (leaks_[i].is_suppressed) continue; |
| bytes += leaks_[i].total_size; |
| allocations += leaks_[i].hit_count; |
| } |
| InternalScopedString summary; |
| summary.append("%zu byte(s) leaked in %zu allocation(s).", bytes, |
| allocations); |
| ReportErrorSummary(summary.data()); |
| } |
| |
| uptr LeakReport::ApplySuppressions() { |
| LeakSuppressionContext *suppressions = GetSuppressionContext(); |
| uptr new_suppressions = false; |
| for (uptr i = 0; i < leaks_.size(); i++) { |
| Suppression *s = suppressions->GetSuppressionForStack( |
| leaks_[i].stack_trace_id, StackDepotGet(leaks_[i].stack_trace_id)); |
| if (s) { |
| s->weight += leaks_[i].total_size; |
| atomic_store_relaxed(&s->hit_count, atomic_load_relaxed(&s->hit_count) + |
| leaks_[i].hit_count); |
| leaks_[i].is_suppressed = true; |
| ++new_suppressions; |
| } |
| } |
| return new_suppressions; |
| } |
| |
| uptr LeakReport::UnsuppressedLeakCount() { |
| uptr result = 0; |
| for (uptr i = 0; i < leaks_.size(); i++) |
| if (!leaks_[i].is_suppressed) result++; |
| return result; |
| } |
| |
| uptr LeakReport::IndirectUnsuppressedLeakCount() { |
| uptr result = 0; |
| for (uptr i = 0; i < leaks_.size(); i++) |
| if (!leaks_[i].is_suppressed && !leaks_[i].is_directly_leaked) |
| result++; |
| return result; |
| } |
| |
| } // namespace __lsan |
| #else // CAN_SANITIZE_LEAKS |
| namespace __lsan { |
| void InitCommonLsan() { } |
| void DoLeakCheck() { } |
| void DoRecoverableLeakCheckVoid() { } |
| void DisableInThisThread() { } |
| void EnableInThisThread() { } |
| } |
| #endif // CAN_SANITIZE_LEAKS |
| |
| using namespace __lsan; |
| |
| extern "C" { |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __lsan_ignore_object(const void *p) { |
| #if CAN_SANITIZE_LEAKS |
| if (!common_flags()->detect_leaks) |
| return; |
| // Cannot use PointsIntoChunk or LsanMetadata here, since the allocator is not |
| // locked. |
| Lock l(&global_mutex); |
| IgnoreObjectResult res = IgnoreObjectLocked(p); |
| if (res == kIgnoreObjectInvalid) |
| VReport(1, "__lsan_ignore_object(): no heap object found at %p", p); |
| if (res == kIgnoreObjectAlreadyIgnored) |
| VReport(1, "__lsan_ignore_object(): " |
| "heap object at %p is already being ignored\n", p); |
| if (res == kIgnoreObjectSuccess) |
| VReport(1, "__lsan_ignore_object(): ignoring heap object at %p\n", p); |
| #endif // CAN_SANITIZE_LEAKS |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __lsan_register_root_region(const void *begin, uptr size) { |
| #if CAN_SANITIZE_LEAKS |
| Lock l(&global_mutex); |
| RootRegion region = {reinterpret_cast<uptr>(begin), size}; |
| root_regions.push_back(region); |
| VReport(1, "Registered root region at %p of size %zu\n", begin, size); |
| #endif // CAN_SANITIZE_LEAKS |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __lsan_unregister_root_region(const void *begin, uptr size) { |
| #if CAN_SANITIZE_LEAKS |
| Lock l(&global_mutex); |
| bool removed = false; |
| for (uptr i = 0; i < root_regions.size(); i++) { |
| RootRegion region = root_regions[i]; |
| if (region.begin == reinterpret_cast<uptr>(begin) && region.size == size) { |
| removed = true; |
| uptr last_index = root_regions.size() - 1; |
| root_regions[i] = root_regions[last_index]; |
| root_regions.pop_back(); |
| VReport(1, "Unregistered root region at %p of size %zu\n", begin, size); |
| break; |
| } |
| } |
| if (!removed) { |
| Report( |
| "__lsan_unregister_root_region(): region at %p of size %zu has not " |
| "been registered.\n", |
| begin, size); |
| Die(); |
| } |
| #endif // CAN_SANITIZE_LEAKS |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __lsan_disable() { |
| #if CAN_SANITIZE_LEAKS |
| __lsan::DisableInThisThread(); |
| #endif |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __lsan_enable() { |
| #if CAN_SANITIZE_LEAKS |
| __lsan::EnableInThisThread(); |
| #endif |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| void __lsan_do_leak_check() { |
| #if CAN_SANITIZE_LEAKS |
| if (common_flags()->detect_leaks) |
| __lsan::DoLeakCheck(); |
| #endif // CAN_SANITIZE_LEAKS |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE |
| int __lsan_do_recoverable_leak_check() { |
| #if CAN_SANITIZE_LEAKS |
| if (common_flags()->detect_leaks) |
| return __lsan::DoRecoverableLeakCheck(); |
| #endif // CAN_SANITIZE_LEAKS |
| return 0; |
| } |
| |
| SANITIZER_INTERFACE_WEAK_DEF(const char *, __lsan_default_options, void) { |
| return ""; |
| } |
| |
| #if !SANITIZER_SUPPORTS_WEAK_HOOKS |
| SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE |
| int __lsan_is_turned_off() { |
| return 0; |
| } |
| |
| SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE |
| const char *__lsan_default_suppressions() { |
| return ""; |
| } |
| #endif |
| } // extern "C" |