From 94825c8924b80518214ad9e3ca1f6589f209592c Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun, 22 Oct 2017 10:00:57 +0200
Subject: [PATCH 6/8] glob: Fix buffer overflow during GLOB_TILDE unescaping
 [BZ #22332]

(cherry picked from commit a159b53fa059947cc2548e3b0d5bdcf7b9630ba8)
---
 ChangeLog    | 6 ++++++
 NEWS         | 4 ++++
 posix/glob.c | 4 ++--
 3 files changed, 12 insertions(+), 2 deletions(-)

#diff --git a/ChangeLog b/ChangeLog
#index 01a1e99d83..77eea1e024 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,3 +1,9 @@
#+2017-10-22  Paul Eggert <eggert@cs.ucla.edu>
#+
#+	[BZ #22332]
#+	* posix/glob.c (__glob): Fix buffer overflow during GLOB_TILDE
#+	unescaping.
#+
# 2017-10-21  Florian Weimer  <fweimer@redhat.com>
# 
# 	* posix/Makefile (tests): Add tst-glob-tilde.
#diff --git a/NEWS b/NEWS
#index a70d21eb40..0531dfa9c6 100644
#--- a/NEWS
#+++ b/NEWS
#@@ -30,6 +30,10 @@ Security related changes:
#   processing, leading to a memory leak and, potentially, to a denial
#   of service.
# 
#+* The glob function, when invoked with GLOB_TILDE and without
#+  GLOB_NOESCAPE, could write past the end of a buffer while
#+  unescaping user names.  Reported by Tim Rühsen.
#+
# The following bugs are resolved with this release:
# 
#   [20790] Fix rpcgen buffer overrun
diff --git a/posix/glob.c b/posix/glob.c
index 026bc063d3..f3fa807700 100644
--- a/posix/glob.c
+++ b/posix/glob.c
@@ -863,11 +863,11 @@ glob (const char *pattern, int flags, int (*errfunc) (const char *, int),
 		  char *p = mempcpy (newp, dirname + 1,
 				     unescape - dirname - 1);
 		  char *q = unescape;
-		  while (*q != '\0')
+		  while (q != end_name)
 		    {
 		      if (*q == '\\')
 			{
-			  if (q[1] == '\0')
+			  if (q + 1 == end_name)
 			    {
 			      /* "~fo\\o\\" unescape to user_name "foo\\",
 				 but "~fo\\o\\/" unescape to user_name
-- 
2.15.1