diff --git a/media/libstagefright/FileSource.cpp b/media/libstagefright/FileSource.cpp
index b6f1af2..dd2579b 100644
--- a/media/libstagefright/FileSource.cpp
+++ b/media/libstagefright/FileSource.cpp
@@ -45,6 +45,10 @@
 }
 
 ssize_t FileSource::readAt(off_t offset, void *data, size_t size) {
+    if (mFile == NULL) {
+        return NO_INIT;
+    }
+
     Mutex::Autolock autoLock(mLock);
 
     if (mLength >= 0) {
@@ -67,6 +71,10 @@
 }
 
 status_t FileSource::getSize(off_t *size) {
+    if (mFile == NULL) {
+        return NO_INIT;
+    }
+
     if (mLength >= 0) {
         *size = mLength;