diff options
Diffstat (limited to 'lib/sanitizer_common/sanitizer_symbolizer_linux.cc')
| -rw-r--r-- | lib/sanitizer_common/sanitizer_symbolizer_linux.cc | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/lib/sanitizer_common/sanitizer_symbolizer_linux.cc b/lib/sanitizer_common/sanitizer_symbolizer_linux.cc new file mode 100644 index 000000000000..4bd3dc8826ef --- /dev/null +++ b/lib/sanitizer_common/sanitizer_symbolizer_linux.cc @@ -0,0 +1,182 @@ +//===-- sanitizer_symbolizer_linux.cc -------------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file is shared between AddressSanitizer and ThreadSanitizer +// run-time libraries. +// Linux-specific implementation of symbolizer parts. +//===----------------------------------------------------------------------===// +#ifdef __linux__ +#include "sanitizer_common.h" +#include "sanitizer_internal_defs.h" +#include "sanitizer_libc.h" +#include "sanitizer_placement_new.h" +#include "sanitizer_symbolizer.h" + +#include <elf.h> +#include <errno.h> +#include <poll.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +#if !defined(__ANDROID__) && !defined(ANDROID) +#include <link.h> +#endif + +namespace __sanitizer { + +static const int kSymbolizerStartupTimeMillis = 10; + +bool StartSymbolizerSubprocess(const char *path_to_symbolizer, + int *input_fd, int *output_fd) { + if (!FileExists(path_to_symbolizer)) { + Report("WARNING: invalid path to external symbolizer!\n"); + return false; + } + + 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]); + } + Report("WARNING: Can't create a socket pair to start " + "external symbolizer (errno: %d)\n", errno); + 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); + + int pid = fork(); + if (pid == -1) { + // Fork() failed. + internal_close(infd[0]); + internal_close(infd[1]); + internal_close(outfd[0]); + internal_close(outfd[1]); + Report("WARNING: failed to fork external symbolizer " + " (errno: %d)\n", errno); + return false; + } else if (pid == 0) { + // Child subprocess. + internal_close(STDOUT_FILENO); + internal_close(STDIN_FILENO); + internal_dup2(outfd[0], STDIN_FILENO); + internal_dup2(infd[1], STDOUT_FILENO); + internal_close(outfd[0]); + internal_close(outfd[1]); + internal_close(infd[0]); + internal_close(infd[1]); + for (int fd = getdtablesize(); fd > 2; fd--) + internal_close(fd); + execl(path_to_symbolizer, path_to_symbolizer, (char*)0); + Exit(1); + } + + // Continue execution in parent process. + internal_close(outfd[0]); + internal_close(infd[1]); + *input_fd = infd[0]; + *output_fd = outfd[1]; + + // Check that symbolizer subprocess started successfully. + int pid_status; + SleepForMillis(kSymbolizerStartupTimeMillis); + int exited_pid = waitpid(pid, &pid_status, WNOHANG); + if (exited_pid != 0) { + // Either waitpid failed, or child has already exited. + Report("WARNING: external symbolizer didn't start up correctly!\n"); + return false; + } + + return true; +} + +#if defined(__ANDROID__) || defined(ANDROID) +uptr GetListOfModules(LoadedModule *modules, uptr max_modules) { + UNIMPLEMENTED(); +} +#else // ANDROID +typedef ElfW(Phdr) Elf_Phdr; + +struct DlIteratePhdrData { + LoadedModule *modules; + uptr current_n; + uptr max_n; +}; + +static const uptr kMaxPathLength = 512; + +static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) { + DlIteratePhdrData *data = (DlIteratePhdrData*)arg; + if (data->current_n == data->max_n) + return 0; + InternalScopedBuffer<char> module_name(kMaxPathLength); + module_name.data()[0] = '\0'; + if (data->current_n == 0) { + // First module is the binary itself. + uptr module_name_len = internal_readlink( + "/proc/self/exe", module_name.data(), module_name.size()); + CHECK_NE(module_name_len, (uptr)-1); + CHECK_LT(module_name_len, module_name.size()); + module_name[module_name_len] = '\0'; + } else if (info->dlpi_name) { + internal_strncpy(module_name.data(), info->dlpi_name, module_name.size()); + } + if (module_name.data()[0] == '\0') + return 0; + void *mem = &data->modules[data->current_n]; + LoadedModule *cur_module = new(mem) LoadedModule(module_name.data(), + info->dlpi_addr); + data->current_n++; + for (int i = 0; i < info->dlpi_phnum; i++) { + const Elf_Phdr *phdr = &info->dlpi_phdr[i]; + if (phdr->p_type == PT_LOAD) { + uptr cur_beg = info->dlpi_addr + phdr->p_vaddr; + uptr cur_end = cur_beg + phdr->p_memsz; + cur_module->addAddressRange(cur_beg, cur_end); + } + } + return 0; +} + +uptr GetListOfModules(LoadedModule *modules, uptr max_modules) { + CHECK(modules); + DlIteratePhdrData data = {modules, 0, max_modules}; + dl_iterate_phdr(dl_iterate_phdr_cb, &data); + return data.current_n; +} +#endif // ANDROID + +} // namespace __sanitizer + +#endif // __linux__ |