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-rw-r--r--lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp487
1 files changed, 487 insertions, 0 deletions
diff --git a/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp b/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
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index 000000000000..c123ecb11206
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+++ b/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
@@ -0,0 +1,487 @@
+//===-- sanitizer_symbolizer_posix_libcdep.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 shared between AddressSanitizer and ThreadSanitizer
+// run-time libraries.
+// POSIX-specific implementation of symbolizer parts.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_platform.h"
+#if SANITIZER_POSIX
+#include "sanitizer_allocator_internal.h"
+#include "sanitizer_common.h"
+#include "sanitizer_file.h"
+#include "sanitizer_flags.h"
+#include "sanitizer_internal_defs.h"
+#include "sanitizer_linux.h"
+#include "sanitizer_placement_new.h"
+#include "sanitizer_posix.h"
+#include "sanitizer_procmaps.h"
+#include "sanitizer_symbolizer_internal.h"
+#include "sanitizer_symbolizer_libbacktrace.h"
+#include "sanitizer_symbolizer_mac.h"
+
+#include <dlfcn.h> // for dlsym()
+#include <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+// C++ demangling function, as required by Itanium C++ ABI. This is weak,
+// because we do not require a C++ ABI library to be linked to a program
+// using sanitizers; if it's not present, we'll just use the mangled name.
+namespace __cxxabiv1 {
+ extern "C" SANITIZER_WEAK_ATTRIBUTE
+ char *__cxa_demangle(const char *mangled, char *buffer,
+ size_t *length, int *status);
+}
+
+namespace __sanitizer {
+
+// Attempts to demangle the name via __cxa_demangle from __cxxabiv1.
+const char *DemangleCXXABI(const char *name) {
+ // FIXME: __cxa_demangle aggressively insists on allocating memory.
+ // There's not much we can do about that, short of providing our
+ // own demangler (libc++abi's implementation could be adapted so that
+ // it does not allocate). For now, we just call it anyway, and we leak
+ // the returned value.
+ if (&__cxxabiv1::__cxa_demangle)
+ if (const char *demangled_name =
+ __cxxabiv1::__cxa_demangle(name, 0, 0, 0))
+ return demangled_name;
+
+ return name;
+}
+
+// As of now, there are no headers for the Swift runtime. Once they are
+// present, we will weakly link since we do not require Swift runtime to be
+// linked.
+typedef char *(*swift_demangle_ft)(const char *mangledName,
+ size_t mangledNameLength, char *outputBuffer,
+ size_t *outputBufferSize, uint32_t flags);
+static swift_demangle_ft swift_demangle_f;
+
+// This must not happen lazily at symbolication time, because dlsym uses
+// malloc and thread-local storage, which is not a good thing to do during
+// symbolication.
+static void InitializeSwiftDemangler() {
+ swift_demangle_f = (swift_demangle_ft)dlsym(RTLD_DEFAULT, "swift_demangle");
+ (void)dlerror(); // Cleanup error message in case of failure
+}
+
+// Attempts to demangle a Swift name. The demangler will return nullptr if a
+// non-Swift name is passed in.
+const char *DemangleSwift(const char *name) {
+ if (!name) return nullptr;
+
+ // Check if we are dealing with a Swift mangled name first.
+ if (name[0] != '_' || name[1] != 'T') {
+ return nullptr;
+ }
+
+ if (swift_demangle_f)
+ return swift_demangle_f(name, internal_strlen(name), 0, 0, 0);
+
+ return nullptr;
+}
+
+const char *DemangleSwiftAndCXX(const char *name) {
+ if (!name) return nullptr;
+ if (const char *swift_demangled_name = DemangleSwift(name))
+ return swift_demangled_name;
+ return DemangleCXXABI(name);
+}
+
+static bool CreateTwoHighNumberedPipes(int *infd_, int *outfd_) {
+ int *infd = NULL;
+ int *outfd = NULL;
+ // The client program may close its stdin and/or stdout and/or stderr
+ // thus allowing socketpair to reuse file descriptors 0, 1 or 2.
+ // In this case the communication between the forked processes may be
+ // broken if either the parent or the child tries to close or duplicate
+ // these descriptors. The loop below produces two pairs of file
+ // descriptors, each greater than 2 (stderr).
+ int sock_pair[5][2];
+ for (int i = 0; i < 5; i++) {
+ if (pipe(sock_pair[i]) == -1) {
+ for (int j = 0; j < i; j++) {
+ internal_close(sock_pair[j][0]);
+ internal_close(sock_pair[j][1]);
+ }
+ return false;
+ } else if (sock_pair[i][0] > 2 && sock_pair[i][1] > 2) {
+ if (infd == NULL) {
+ infd = sock_pair[i];
+ } else {
+ outfd = sock_pair[i];
+ for (int j = 0; j < i; j++) {
+ if (sock_pair[j] == infd) continue;
+ internal_close(sock_pair[j][0]);
+ internal_close(sock_pair[j][1]);
+ }
+ break;
+ }
+ }
+ }
+ CHECK(infd);
+ CHECK(outfd);
+ infd_[0] = infd[0];
+ infd_[1] = infd[1];
+ outfd_[0] = outfd[0];
+ outfd_[1] = outfd[1];
+ return true;
+}
+
+bool SymbolizerProcess::StartSymbolizerSubprocess() {
+ if (!FileExists(path_)) {
+ if (!reported_invalid_path_) {
+ Report("WARNING: invalid path to external symbolizer!\n");
+ reported_invalid_path_ = true;
+ }
+ return false;
+ }
+
+ const char *argv[kArgVMax];
+ GetArgV(path_, argv);
+ pid_t pid;
+
+ if (use_posix_spawn_) {
+#if SANITIZER_MAC
+ fd_t fd = internal_spawn(argv, &pid);
+ if (fd == kInvalidFd) {
+ Report("WARNING: failed to spawn external symbolizer (errno: %d)\n",
+ errno);
+ return false;
+ }
+
+ input_fd_ = fd;
+ output_fd_ = fd;
+#else // SANITIZER_MAC
+ UNIMPLEMENTED();
+#endif // SANITIZER_MAC
+ } else {
+ fd_t infd[2] = {}, outfd[2] = {};
+ if (!CreateTwoHighNumberedPipes(infd, outfd)) {
+ Report("WARNING: Can't create a socket pair to start "
+ "external symbolizer (errno: %d)\n", errno);
+ return false;
+ }
+
+ pid = StartSubprocess(path_, argv, /* stdin */ outfd[0],
+ /* stdout */ infd[1]);
+ if (pid < 0) {
+ internal_close(infd[0]);
+ internal_close(outfd[1]);
+ return false;
+ }
+
+ input_fd_ = infd[0];
+ output_fd_ = outfd[1];
+ }
+
+ CHECK_GT(pid, 0);
+
+ // Check that symbolizer subprocess started successfully.
+ SleepForMillis(kSymbolizerStartupTimeMillis);
+ if (!IsProcessRunning(pid)) {
+ // Either waitpid failed, or child has already exited.
+ Report("WARNING: external symbolizer didn't start up correctly!\n");
+ return false;
+ }
+
+ return true;
+}
+
+class Addr2LineProcess : public SymbolizerProcess {
+ public:
+ Addr2LineProcess(const char *path, const char *module_name)
+ : SymbolizerProcess(path), module_name_(internal_strdup(module_name)) {}
+
+ const char *module_name() const { return module_name_; }
+
+ private:
+ void GetArgV(const char *path_to_binary,
+ const char *(&argv)[kArgVMax]) const override {
+ int i = 0;
+ argv[i++] = path_to_binary;
+ argv[i++] = "-iCfe";
+ argv[i++] = module_name_;
+ argv[i++] = nullptr;
+ }
+
+ bool ReachedEndOfOutput(const char *buffer, uptr length) const override;
+
+ bool ReadFromSymbolizer(char *buffer, uptr max_length) override {
+ if (!SymbolizerProcess::ReadFromSymbolizer(buffer, max_length))
+ return false;
+ // The returned buffer is empty when output is valid, but exceeds
+ // max_length.
+ if (*buffer == '\0')
+ return true;
+ // We should cut out output_terminator_ at the end of given buffer,
+ // appended by addr2line to mark the end of its meaningful output.
+ // We cannot scan buffer from it's beginning, because it is legal for it
+ // to start with output_terminator_ in case given offset is invalid. So,
+ // scanning from second character.
+ char *garbage = internal_strstr(buffer + 1, output_terminator_);
+ // This should never be NULL since buffer must end up with
+ // output_terminator_.
+ CHECK(garbage);
+ // Trim the buffer.
+ garbage[0] = '\0';
+ return true;
+ }
+
+ const char *module_name_; // Owned, leaked.
+ static const char output_terminator_[];
+};
+
+const char Addr2LineProcess::output_terminator_[] = "??\n??:0\n";
+
+bool Addr2LineProcess::ReachedEndOfOutput(const char *buffer,
+ uptr length) const {
+ const size_t kTerminatorLen = sizeof(output_terminator_) - 1;
+ // Skip, if we read just kTerminatorLen bytes, because Addr2Line output
+ // should consist at least of two pairs of lines:
+ // 1. First one, corresponding to given offset to be symbolized
+ // (may be equal to output_terminator_, if offset is not valid).
+ // 2. Second one for output_terminator_, itself to mark the end of output.
+ if (length <= kTerminatorLen) return false;
+ // Addr2Line output should end up with output_terminator_.
+ return !internal_memcmp(buffer + length - kTerminatorLen,
+ output_terminator_, kTerminatorLen);
+}
+
+class Addr2LinePool : public SymbolizerTool {
+ public:
+ explicit Addr2LinePool(const char *addr2line_path,
+ LowLevelAllocator *allocator)
+ : addr2line_path_(addr2line_path), allocator_(allocator) {
+ addr2line_pool_.reserve(16);
+ }
+
+ bool SymbolizePC(uptr addr, SymbolizedStack *stack) override {
+ if (const char *buf =
+ SendCommand(stack->info.module, stack->info.module_offset)) {
+ ParseSymbolizePCOutput(buf, stack);
+ return true;
+ }
+ return false;
+ }
+
+ bool SymbolizeData(uptr addr, DataInfo *info) override {
+ return false;
+ }
+
+ private:
+ const char *SendCommand(const char *module_name, uptr module_offset) {
+ Addr2LineProcess *addr2line = 0;
+ for (uptr i = 0; i < addr2line_pool_.size(); ++i) {
+ if (0 ==
+ internal_strcmp(module_name, addr2line_pool_[i]->module_name())) {
+ addr2line = addr2line_pool_[i];
+ break;
+ }
+ }
+ if (!addr2line) {
+ addr2line =
+ new(*allocator_) Addr2LineProcess(addr2line_path_, module_name);
+ addr2line_pool_.push_back(addr2line);
+ }
+ CHECK_EQ(0, internal_strcmp(module_name, addr2line->module_name()));
+ char buffer[kBufferSize];
+ internal_snprintf(buffer, kBufferSize, "0x%zx\n0x%zx\n",
+ module_offset, dummy_address_);
+ return addr2line->SendCommand(buffer);
+ }
+
+ static const uptr kBufferSize = 64;
+ const char *addr2line_path_;
+ LowLevelAllocator *allocator_;
+ InternalMmapVector<Addr2LineProcess*> addr2line_pool_;
+ static const uptr dummy_address_ =
+ FIRST_32_SECOND_64(UINT32_MAX, UINT64_MAX);
+};
+
+#if SANITIZER_SUPPORTS_WEAK_HOOKS
+extern "C" {
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+bool __sanitizer_symbolize_code(const char *ModuleName, u64 ModuleOffset,
+ char *Buffer, int MaxLength);
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+bool __sanitizer_symbolize_data(const char *ModuleName, u64 ModuleOffset,
+ char *Buffer, int MaxLength);
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+void __sanitizer_symbolize_flush();
+SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
+int __sanitizer_symbolize_demangle(const char *Name, char *Buffer,
+ int MaxLength);
+} // extern "C"
+
+class InternalSymbolizer : public SymbolizerTool {
+ public:
+ static InternalSymbolizer *get(LowLevelAllocator *alloc) {
+ if (__sanitizer_symbolize_code != 0 &&
+ __sanitizer_symbolize_data != 0) {
+ return new(*alloc) InternalSymbolizer();
+ }
+ return 0;
+ }
+
+ bool SymbolizePC(uptr addr, SymbolizedStack *stack) override {
+ bool result = __sanitizer_symbolize_code(
+ stack->info.module, stack->info.module_offset, buffer_, kBufferSize);
+ if (result) ParseSymbolizePCOutput(buffer_, stack);
+ return result;
+ }
+
+ bool SymbolizeData(uptr addr, DataInfo *info) override {
+ bool result = __sanitizer_symbolize_data(info->module, info->module_offset,
+ buffer_, kBufferSize);
+ if (result) {
+ ParseSymbolizeDataOutput(buffer_, info);
+ info->start += (addr - info->module_offset); // Add the base address.
+ }
+ return result;
+ }
+
+ void Flush() override {
+ if (__sanitizer_symbolize_flush)
+ __sanitizer_symbolize_flush();
+ }
+
+ const char *Demangle(const char *name) override {
+ if (__sanitizer_symbolize_demangle) {
+ for (uptr res_length = 1024;
+ res_length <= InternalSizeClassMap::kMaxSize;) {
+ char *res_buff = static_cast<char*>(InternalAlloc(res_length));
+ uptr req_length =
+ __sanitizer_symbolize_demangle(name, res_buff, res_length);
+ if (req_length > res_length) {
+ res_length = req_length + 1;
+ InternalFree(res_buff);
+ continue;
+ }
+ return res_buff;
+ }
+ }
+ return name;
+ }
+
+ private:
+ InternalSymbolizer() { }
+
+ static const int kBufferSize = 16 * 1024;
+ char buffer_[kBufferSize];
+};
+#else // SANITIZER_SUPPORTS_WEAK_HOOKS
+
+class InternalSymbolizer : public SymbolizerTool {
+ public:
+ static InternalSymbolizer *get(LowLevelAllocator *alloc) { return 0; }
+};
+
+#endif // SANITIZER_SUPPORTS_WEAK_HOOKS
+
+const char *Symbolizer::PlatformDemangle(const char *name) {
+ return DemangleSwiftAndCXX(name);
+}
+
+static SymbolizerTool *ChooseExternalSymbolizer(LowLevelAllocator *allocator) {
+ const char *path = common_flags()->external_symbolizer_path;
+ const char *binary_name = path ? StripModuleName(path) : "";
+ if (path && path[0] == '\0') {
+ VReport(2, "External symbolizer is explicitly disabled.\n");
+ return nullptr;
+ } else if (!internal_strcmp(binary_name, "llvm-symbolizer")) {
+ VReport(2, "Using llvm-symbolizer at user-specified path: %s\n", path);
+ return new(*allocator) LLVMSymbolizer(path, allocator);
+ } else if (!internal_strcmp(binary_name, "atos")) {
+#if SANITIZER_MAC
+ VReport(2, "Using atos at user-specified path: %s\n", path);
+ return new(*allocator) AtosSymbolizer(path, allocator);
+#else // SANITIZER_MAC
+ Report("ERROR: Using `atos` is only supported on Darwin.\n");
+ Die();
+#endif // SANITIZER_MAC
+ } else if (!internal_strcmp(binary_name, "addr2line")) {
+ VReport(2, "Using addr2line at user-specified path: %s\n", path);
+ return new(*allocator) Addr2LinePool(path, allocator);
+ } else if (path) {
+ Report("ERROR: External symbolizer path is set to '%s' which isn't "
+ "a known symbolizer. Please set the path to the llvm-symbolizer "
+ "binary or other known tool.\n", path);
+ Die();
+ }
+
+ // Otherwise symbolizer program is unknown, let's search $PATH
+ CHECK(path == nullptr);
+#if SANITIZER_MAC
+ if (const char *found_path = FindPathToBinary("atos")) {
+ VReport(2, "Using atos found at: %s\n", found_path);
+ return new(*allocator) AtosSymbolizer(found_path, allocator);
+ }
+#endif // SANITIZER_MAC
+ if (const char *found_path = FindPathToBinary("llvm-symbolizer")) {
+ VReport(2, "Using llvm-symbolizer found at: %s\n", found_path);
+ return new(*allocator) LLVMSymbolizer(found_path, allocator);
+ }
+ if (common_flags()->allow_addr2line) {
+ if (const char *found_path = FindPathToBinary("addr2line")) {
+ VReport(2, "Using addr2line found at: %s\n", found_path);
+ return new(*allocator) Addr2LinePool(found_path, allocator);
+ }
+ }
+ return nullptr;
+}
+
+static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
+ LowLevelAllocator *allocator) {
+ if (!common_flags()->symbolize) {
+ VReport(2, "Symbolizer is disabled.\n");
+ return;
+ }
+ if (IsAllocatorOutOfMemory()) {
+ VReport(2, "Cannot use internal symbolizer: out of memory\n");
+ } else if (SymbolizerTool *tool = InternalSymbolizer::get(allocator)) {
+ VReport(2, "Using internal symbolizer.\n");
+ list->push_back(tool);
+ return;
+ }
+ if (SymbolizerTool *tool = LibbacktraceSymbolizer::get(allocator)) {
+ VReport(2, "Using libbacktrace symbolizer.\n");
+ list->push_back(tool);
+ return;
+ }
+
+ if (SymbolizerTool *tool = ChooseExternalSymbolizer(allocator)) {
+ list->push_back(tool);
+ }
+
+#if SANITIZER_MAC
+ VReport(2, "Using dladdr symbolizer.\n");
+ list->push_back(new(*allocator) DlAddrSymbolizer());
+#endif // SANITIZER_MAC
+}
+
+Symbolizer *Symbolizer::PlatformInit() {
+ IntrusiveList<SymbolizerTool> list;
+ list.clear();
+ ChooseSymbolizerTools(&list, &symbolizer_allocator_);
+ return new(symbolizer_allocator_) Symbolizer(list);
+}
+
+void Symbolizer::LateInitialize() {
+ Symbolizer::GetOrInit();
+ InitializeSwiftDemangler();
+}
+
+} // namespace __sanitizer
+
+#endif // SANITIZER_POSIX