From patchwork Wed Dec  2 15:01:55 2015
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Subject: [STABLE] parsers: fix parse_dirstate to check len before unpacking
 header (issue4979)
From: Yuya Nishihara <yuya@tcha.org>
X-Patchwork-Id: 11745
Message-Id: <f5e8cb813a4d5c0665c7.1449068515@mimosa>
To: mercurial-devel@selenic.com
Date: Thu, 03 Dec 2015 00:01:55 +0900

# HG changeset patch
# User Yuya Nishihara <yuya@tcha.org>
# Date 1449065098 -32400
#      Wed Dec 02 23:04:58 2015 +0900
# Branch stable
# 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;