Breakpad support for ASan: take 2.

chrome/app/breakpad_linux.cc

Index: chrome/app/breakpad_linux.cc
===================================================================
--- chrome/app/breakpad_linux.cc	(revision 152529)
+++ chrome/app/breakpad_linux.cc	(working copy)
@@ -54,6 +54,10 @@
 #include "sandbox/linux/seccomp-legacy/linux_syscall_support.h"
 #endif
 
+#if defined(ADDRESS_SANITIZER)
+#include <ucontext.h> // for getcontext().
+#endif
+
 #if defined(OS_ANDROID)
 #define STAT_STRUCT struct stat
 #define FSTAT_FUNC fstat
@@ -73,12 +77,21 @@
 
 namespace {
 
+#if !defined(ADDRESS_SANITIZER)
 const char kUploadURL[] = "https://clients2.google.com/cr/report";
+#else
+// AddressSanitizer should currently upload the crash reports to the staging
+// crash server.
+const char kUploadURL[] = "https://clients2.google.com/cr/staging_report";
+#endif
 
 bool g_is_crash_reporter_enabled = false;
 uint64_t g_process_start_time = 0;
 char* g_crash_log_path = NULL;
 ExceptionHandler* g_breakpad = NULL;
+#if defined(ADDRESS_SANITIZER)
+char* g_asan_report_str = NULL;
+#endif
 
 // Writes the value |v| as 16 hex characters to the memory pointed at by
 // |output|.
@@ -171,6 +184,9 @@
 const char g_quote_msg[] = "\"";
 const char g_dashdash_msg[] = "--";
 const char g_dump_msg[] = "upload_file_minidump\"; filename=\"dump\"";
+#if defined(ADDRESS_SANITIZER)
+const char g_log_msg[] = "upload_file_log\"; filename=\"log\"";
+#endif
 const char g_content_type_msg[] = "Content-Type: application/octet-stream";
 
 // MimeWriter manages an iovec for writing MIMEs to a file.
@@ -210,10 +226,10 @@
                            size_t chunk_size,
                            bool strip_trailing_spaces);
 
-  // Add binary file dump. Currently this is only done once, so the name is
-  // fixed.
-  void AddFileDump(uint8_t* file_data,
-                   size_t file_size);
+  // Add binary file contents to be uploaded with the specified filename.
+  void AddFileContents(const char* filename_msg,
+                       uint8_t* file_data,
+                       size_t file_size);
 
   // Flush any pending iovecs to the output file.
   void Flush() {
@@ -312,10 +328,10 @@
   }
 }
 
-void MimeWriter::AddFileDump(uint8_t* file_data,
-                             size_t file_size) {
+void MimeWriter::AddFileContents(const char* filename_msg, uint8_t* file_data,
+                                 size_t file_size) {
   AddString(g_form_data_msg);
-  AddString(g_dump_msg);
+  AddString(filename_msg);
   AddString(g_rn);
   AddString(g_content_type_msg);
   AddString(g_rn);
@@ -372,6 +388,15 @@
 
   BreakpadInfo info;
   info.filename = minidump.path();
+#if defined(ADDRESS_SANITIZER)
+  google_breakpad::PageAllocator allocator;
+  const size_t log_path_len = my_strlen(minidump.path());
+  char* log_path = reinterpret_cast<char*>(allocator.Alloc(log_path_len + 1));
+  my_memcpy(log_path, minidump.path(), log_path_len);
+  my_memcpy(log_path + log_path_len - 4, ".log", 4);
+  log_path[log_path_len] = '\0';
+  info.log_filename = log_path;
+#endif
   info.process_type = "browser";
   info.process_type_length = 7;
   info.crash_url = NULL;
@@ -404,6 +429,18 @@
 }
 #endif
 
+#if defined(ADDRESS_SANITIZER)
+extern "C"
+void __asan_set_error_report_callback(void (*cb)(const char*));
+
+extern "C"
+void AsanLinuxBreakpadCallback(const char* report) {
+  g_asan_report_str = const_cast<char*>(report);

[Lei Zhang, 2012/08/21 18:35:17]

nit: Can we make |g_asan_report_str| const char and avoid the const_cast here?

[Alexander Potapenko, 2012/08/22 12:15:08]

Ok. This however has introduced a const_cast below.

[Lei Zhang, 2012/08/22 18:41:55]

Blah.

+  // Send minidump here.
+  g_breakpad->SimulateSignalDelivery(9);

[Lei Zhang, 2012/08/21 18:35:17]

nit: Can we use a SIGKILL constant from signal.h here?

[Alexander Potapenko, 2012/08/22 12:15:08]

Done.

+}
+#endif
+
 void EnableCrashDumping(bool unattended) {
   g_is_crash_reporter_enabled = true;
 
@@ -483,7 +520,12 @@
   static const unsigned kControlMsgSpaceSize = CMSG_SPACE(kControlMsgSize);
   static const unsigned kControlMsgLenSize = CMSG_LEN(kControlMsgSize);
 
+#if !defined(ADDRESS_SANITIZER)
   const size_t kIovSize = 8;
+#else
+  // Additional field to pass the AddressSanitizer log to the crash handler.
+  const size_t kIovSize = 9;
+#endif
   struct kernel_msghdr msg;
   my_memset(&msg, 0, sizeof(struct kernel_msghdr));
   struct kernel_iovec iov[kIovSize];
@@ -503,6 +545,10 @@
   iov[6].iov_len = sizeof(g_process_start_time);
   iov[7].iov_base = &base::g_oom_size;
   iov[7].iov_len = sizeof(base::g_oom_size);
+#if defined(ADDRESS_SANITIZER)
+  iov[8].iov_base = g_asan_report_str;
+  iov[8].iov_len = kMaxAsanReportSize + 1;
+#endif
 
   msg.msg_iov = iov;
   msg.msg_iovlen = kIovSize;
@@ -551,40 +597,60 @@
 
 }  // namespace
 
-void HandleCrashDump(const BreakpadInfo& info) {
+void LoadDataFromFile(google_breakpad::PageAllocator& allocator,
+                      const BreakpadInfo& info, int* fd,
+                      uint8_t** file_data, size_t* size,
+                      const char* filename) {

[Lei Zhang, 2012/08/21 18:35:17]

nit: Can we move |filename| in front of the out parameters?

[Alexander Potapenko, 2012/08/22 12:15:08]

Done.

   // WARNING: this code runs in a compromised context. It may not call into
   // libc nor allocate memory normally.
+  *fd = sys_open(filename, O_RDONLY, 0);
+  *size = 0;
 
-  const int dumpfd = sys_open(info.filename, O_RDONLY, 0);
-  if (dumpfd < 0) {
+  if (*fd < 0) {
     static const char msg[] = "Cannot upload crash dump: failed to open\n";
     WriteLog(msg, sizeof(msg));
     return;
   }
   STAT_STRUCT st;
-  if (FSTAT_FUNC(dumpfd, &st) != 0) {
+  if (FSTAT_FUNC(*fd, &st) != 0) {
     static const char msg[] = "Cannot upload crash dump: stat failed\n";
     WriteLog(msg, sizeof(msg));
-    IGNORE_RET(sys_close(dumpfd));
+    IGNORE_RET(sys_close(*fd));
     return;
   }
 
-  google_breakpad::PageAllocator allocator;
-
-  uint8_t* dump_data = reinterpret_cast<uint8_t*>(allocator.Alloc(st.st_size));
-  if (!dump_data) {
+  *file_data = reinterpret_cast<uint8_t*>(allocator.Alloc(st.st_size));
+  if (!(*file_data)) {
     static const char msg[] = "Cannot upload crash dump: cannot alloc\n";
     WriteLog(msg, sizeof(msg));
-    IGNORE_RET(sys_close(dumpfd));
+    IGNORE_RET(sys_close(*fd));
     return;
   }
+  my_memset(*file_data, 0xf, st.st_size);
 
-  sys_read(dumpfd, dump_data, st.st_size);
-  IGNORE_RET(sys_close(dumpfd));
+  *size = st.st_size;
+  sys_read(*fd, *file_data, *size);
+  IGNORE_RET(sys_close(*fd));
+}
 
+void HandleCrashDump(const BreakpadInfo& info) {
+  int dumpfd;
+  size_t dump_size;
+  uint8_t *dump_data;
+  google_breakpad::PageAllocator allocator;
+  LoadDataFromFile(allocator, info, &dumpfd, &dump_data, &dump_size,
+                   info.filename);
+#if defined(ADDRESS_SANITIZER)
+  int logfd;
+  size_t log_size;
+  uint8_t *log_data;
+  // Load the AddressSanitizer log into log_data.
+  LoadDataFromFile(allocator, info, &logfd, &log_data, &log_size,
+                   info.log_filename);
+#endif
+
   // We need to build a MIME block for uploading to the server. Since we are
   // going to fork and run wget, it needs to be written to a temp file.
-
   const int ufd = sys_open("/dev/urandom", O_RDONLY, 0);
   if (ufd < 0) {
     static const char msg[] = "Cannot upload crash dump because /dev/urandom"
@@ -916,7 +982,12 @@
     writer.Flush();
   }
 
-  writer.AddFileDump(dump_data, st.st_size);
+  writer.AddFileContents(g_dump_msg, dump_data, dump_size);
+#if defined(ADDRESS_SANITIZER)
+  // Append a multipart boundary and the contents of the AddressSanitizer log.
+  writer.AddBoundary();
+  writer.AddFileContents(g_log_msg, log_data, log_size);
+#endif
   writer.AddEnd();
   writer.Flush();
 
@@ -1097,6 +1168,9 @@
 
     // Helper process.
     IGNORE_RET(sys_unlink(info.filename));
+#if defined(ADDRESS_SANITIZER)
+    IGNORE_RET(sys_unlink(info.log_filename));
+#endif
     IGNORE_RET(sys_unlink(temp_file));
     sys__exit(0);
   }
@@ -1158,6 +1232,10 @@
     g_process_start_time = 0;
 
   logging::SetDumpWithoutCrashingFunction(&DumpProcess);
+#if defined(ADDRESS_SANITIZER)
+  // Register the callback for AddressSanitizer error reporting.
+  __asan_set_error_report_callback(AsanLinuxBreakpadCallback);
+#endif
 }
 
 bool IsCrashReporterEnabled() {