diff --git a/src/build/libroot/fs.cpp b/src/build/libroot/fs.cpp
index f8c0af2798..d1f7e8bfbf 100644
--- a/src/build/libroot/fs.cpp
+++ b/src/build/libroot/fs.cpp
@@ -979,7 +979,7 @@ write_pos(int fd, off_t pos, const void *buffer, size_t bufferSize)
 			return -1;
 		}
 
-		return 0;
+		return bufferSize;
 	}
 
 	// seek