# HG changeset patch
# User Yuya Nishihara <yuya@tcha.org>
# Date 2015-12-02 14:04:58
# Node ID f5e8cb813a4d5c0665c7e144d96810b4763c42d1
# Parent  7e1fac6c0a9ce6afd3edeed5e47bcca343155d8a

parsers: fix parse_dirstate to check len before unpacking header (issue4979)

diff --git a/mercurial/parsers.c b/mercurial/parsers.c
--- a/mercurial/parsers.c
+++ b/mercurial/parsers.c
@@ -493,6 +493,11 @@ static PyObject *parse_dirstate(PyObject
 
 	/* read filenames */
 	while (pos >= 40 && pos < len) {
+		if (pos + 17 > len) {
+			PyErr_SetString(PyExc_ValueError,
+					"overflow in dirstate");
+			goto quit;
+		}
 		cur = str + pos;
 		/* unpack header */
 		state = *cur;