Merge changes I40575081,I1ca8f8cf,I38bfd273

* changes:
  clang-format Utils.cpp
  vold: fsync both file and directory after write keys
  vold: Introduce android::vold::writeStringToFile

FsCrypt.cpp

@@ -60,10 +60,10 @@
 #include <android-base/unique_fd.h>
 
 using android::base::StringPrintf;
-using android::base::WriteStringToFile;
 using android::fs_mgr::GetEntryForMountPoint;
 using android::vold::kEmptyAuthentication;
 using android::vold::KeyBuffer;
+using android::vold::writeStringToFile;
 
 namespace {
 
@@ -351,18 +351,14 @@ bool fscrypt_initialize_global_de() {
 
     std::string modestring = device_ref.contents_mode + ":" + device_ref.filenames_mode;
     std::string mode_filename = std::string("/data") + fscrypt_key_mode;
-    if (!android::base::WriteStringToFile(modestring, mode_filename)) {
-        PLOG(ERROR) << "Cannot save type";
-        return false;
-    }
+    if (!android::vold::writeStringToFile(modestring, mode_filename)) return false;
 
     std::string ref_filename = std::string("/data") + fscrypt_key_ref;
-    if (!android::base::WriteStringToFile(device_ref.key_raw_ref, ref_filename)) {
-        PLOG(ERROR) << "Cannot save key reference to:" << ref_filename;
-        return false;
-    }
+    if (!android::vold::writeStringToFile(device_ref.key_raw_ref, ref_filename)) return false;
+
     LOG(INFO) << "Wrote system DE key reference to:" << ref_filename;
 
+    if (!android::vold::FsyncDirectory(device_key_dir)) return false;
     s_global_de_initialized = true;
     return true;
 }
@@ -419,7 +415,7 @@ static void drop_caches() {
     // Clean any dirty pages (otherwise they won't be dropped).
     sync();
     // Drop inode and page caches.
-    if (!WriteStringToFile("3", "/proc/sys/vm/drop_caches")) {
+    if (!writeStringToFile("3", "/proc/sys/vm/drop_caches")) {
         PLOG(ERROR) << "Failed to drop caches during key eviction";
     }
 }

KeyStorage.cpp

@@ -147,33 +147,6 @@ static bool readFileToString(const std::string& filename, std::string* result) {
     return true;
 }
 
-static bool writeStringToFile(const std::string& payload, const std::string& filename) {
-    android::base::unique_fd fd(TEMP_FAILURE_RETRY(
-        open(filename.c_str(), O_WRONLY | O_CREAT | O_NOFOLLOW | O_TRUNC | O_CLOEXEC, 0666)));
-    if (fd == -1) {
-        PLOG(ERROR) << "Failed to open " << filename;
-        return false;
-    }
-    if (!android::base::WriteStringToFd(payload, fd)) {
-        PLOG(ERROR) << "Failed to write to " << filename;
-        unlink(filename.c_str());
-        return false;
-    }
-    // fsync as close won't guarantee flush data
-    // see close(2), fsync(2) and b/68901441
-    if (fsync(fd) == -1) {
-        if (errno == EROFS || errno == EINVAL) {
-            PLOG(WARNING) << "Skip fsync " << filename
-                          << " on a file system does not support synchronization";
-        } else {
-            PLOG(ERROR) << "Failed to fsync " << filename;
-            unlink(filename.c_str());
-            return false;
-        }
-    }
-    return true;
-}
-
 static bool readRandomBytesOrLog(size_t count, std::string* out) {
     auto status = ReadRandomBytes(count, *out);
     if (status != OK) {

Utils.cpp

@@ -42,6 +42,7 @@
 #include <sys/sysmacros.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <unistd.h>
 
 #include <list>
 #include <mutex>
@@ -840,5 +841,32 @@ bool FsyncDirectory(const std::string& dirname) {
     return true;
 }
 
+bool writeStringToFile(const std::string& payload, const std::string& filename) {
+    android::base::unique_fd fd(TEMP_FAILURE_RETRY(
+        open(filename.c_str(), O_WRONLY | O_CREAT | O_NOFOLLOW | O_TRUNC | O_CLOEXEC, 0666)));
+    if (fd == -1) {
+        PLOG(ERROR) << "Failed to open " << filename;
+        return false;
+    }
+    if (!android::base::WriteStringToFd(payload, fd)) {
+        PLOG(ERROR) << "Failed to write to " << filename;
+        unlink(filename.c_str());
+        return false;
+    }
+    // fsync as close won't guarantee flush data
+    // see close(2), fsync(2) and b/68901441
+    if (fsync(fd) == -1) {
+        if (errno == EROFS || errno == EINVAL) {
+            PLOG(WARNING) << "Skip fsync " << filename
+                          << " on a file system does not support synchronization";
+        } else {
+            PLOG(ERROR) << "Failed to fsync " << filename;
+            unlink(filename.c_str());
+            return false;
+        }
+    }
+    return true;
+}
+
 }  // namespace vold
 }  // namespace android

Utils.h

@@ -134,6 +134,7 @@ status_t WaitForFile(const char* filename, std::chrono::nanoseconds timeout);
 
 bool FsyncDirectory(const std::string& dirname);
 
+bool writeStringToFile(const std::string& payload, const std::string& filename);
 }  // namespace vold
 }  // namespace android