diff --git a/diff.c b/diff.c
index 2daa732a36..db2cd5d35f 100644
--- a/diff.c
+++ b/diff.c
@@ -550,6 +550,10 @@ static void emit_rewrite_diff(const char *name_a,
 		emit_rewrite_lines(&ecbdata, '-', data_one, size_one);
 	if (lc_b)
 		emit_rewrite_lines(&ecbdata, '+', data_two, size_two);
+	if (textconv_one)
+		free(data_one);
+	if (textconv_two)
+		free(data_two);
 }
 
 struct diff_words_buffer {