Fix string.format() for non-finite numbers.

diff --git a/src/lib_string.c b/src/lib_string.c
index c1b584d82cbef9b1a5cbe4b3872b21b1440c8be3..8ca9ef01bd5b46937462cd2e50d627557cc2c875 100644 (file)
--- a/src/lib_string.c
+++ b/src/lib_string.c
@@ -746,6 +746,7 @@ LJLIB_CF(string_format)
            nbuf[len-2] = nbuf[len-2] - 0x20;
            nbuf[len-1] = nbuf[len-1] - 0x20;
          }
+         nbuf[len] = '\0';
          for (p = form; *p < 'e' && *p != '.'; p++) ;
          *p++ = 's'; *p = '\0';
          sprintf(buff, form, nbuf);