diff --git a/src/utils/os.h b/src/utils/os.h
index 2c24631bf..9e496fb65 100644
--- a/src/utils/os.h
+++ b/src/utils/os.h
@@ -246,6 +246,13 @@ char * os_readfile(const char *name, size_t *len);
  */
 int os_file_exists(const char *fname);
 
+/**
+ * os_fdatasync - Sync a file's (for a given stream) state with storage device
+ * @stream: the stream to be flushed
+ * Returns: 0 if the operation succeeded or -1 on failure
+ */
+int os_fdatasync(FILE *stream);
+
 /**
  * os_zalloc - Allocate and zero memory
  * @size: Number of bytes to allocate
diff --git a/src/utils/os_internal.c b/src/utils/os_internal.c
index 77733ad91..ed6eb3c6b 100644
--- a/src/utils/os_internal.c
+++ b/src/utils/os_internal.c
@@ -243,6 +243,12 @@ char * os_readfile(const char *name, size_t *len)
 }
 
 
+int os_fdatasync(FILE *stream)
+{
+	return 0;
+}
+
+
 void * os_zalloc(size_t size)
 {
 	void *n = os_malloc(size);
diff --git a/src/utils/os_none.c b/src/utils/os_none.c
index 83fe02516..0c3214d32 100644
--- a/src/utils/os_none.c
+++ b/src/utils/os_none.c
@@ -102,6 +102,12 @@ char * os_readfile(const char *name, size_t *len)
 }
 
 
+int os_fdatasync(FILE *stream)
+{
+	return 0;
+}
+
+
 void * os_zalloc(size_t size)
 {
 	return NULL;
diff --git a/src/utils/os_unix.c b/src/utils/os_unix.c
index 089b880bd..4754dd7a1 100644
--- a/src/utils/os_unix.c
+++ b/src/utils/os_unix.c
@@ -418,6 +418,14 @@ int os_file_exists(const char *fname)
 }
 
 
+int os_fdatasync(FILE *stream)
+{
+	if (!fflush(stream))
+		return fdatasync(fileno(stream));
+	return -1;
+}
+
+
 #ifndef WPA_TRACE
 void * os_zalloc(size_t size)
 {
diff --git a/src/utils/os_win32.c b/src/utils/os_win32.c
index 296ea13f1..dea27b9f2 100644
--- a/src/utils/os_win32.c
+++ b/src/utils/os_win32.c
@@ -216,6 +216,24 @@ char * os_readfile(const char *name, size_t *len)
 }
 
 
+int os_fdatasync(FILE *stream)
+{
+	HANDLE h;
+
+	if (stream == NULL)
+		return -1;
+
+	h = (HANDLE) _get_osfhandle(_fileno(stream));
+	if (h == INVALID_HANDLE_VALUE)
+		return -1;
+
+	if (!FlushFileBuffers(h))
+		return -1;
+
+	return 0;
+}
+
+
 void * os_zalloc(size_t size)
 {
 	return calloc(1, size);
diff --git a/wpa_supplicant/config_file.c b/wpa_supplicant/config_file.c
index 2af187dd4..fb438ea43 100644
--- a/wpa_supplicant/config_file.c
+++ b/wpa_supplicant/config_file.c
@@ -1361,6 +1361,8 @@ int wpa_config_write(const char *name, struct wpa_config *config)
 	}
 #endif /* CONFIG_NO_CONFIG_BLOBS */
 
+	os_fdatasync(f);
+
 	fclose(f);
 
 	if (tmp_name) {