From a159b53fa059947cc2548e3b0d5bdcf7b9630ba8 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Sun, 22 Oct 2017 10:00:57 +0200 Subject: [PATCH] glob: Fix buffer overflow during GLOB_TILDE unescaping [BZ #22332] --- ChangeLog | 6 ++++++ NEWS | 4 ++++ posix/glob.c | 4 ++-- 3 files changed, 12 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index bc15aef2ba..d2f0858f84 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2017-10-22 Paul Eggert + + [BZ #22332] + * posix/glob.c (__glob): Fix buffer overflow during GLOB_TILDE + unescaping. + 2017-10-21 Florian Weimer * posix/Makefile (tests): Add tst-glob-tilde. diff --git a/NEWS b/NEWS index c38fb88ac4..8e040f1f3b 100644 --- a/NEWS +++ b/NEWS @@ -82,6 +82,10 @@ 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: [The release manager will add the list generated by diff --git a/posix/glob.c b/posix/glob.c index 15a6c0cf13..cb39779d07 100644 --- a/posix/glob.c +++ b/posix/glob.c @@ -770,11 +770,11 @@ __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