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# Source: https://sourceware.org/git/?p=glibc.git;a=patch;h=87bd4186da10371f46e2f1a7bf7c0a45bb04f1ac
# Modified: removed Changelog and NEWS from patch to apply across multiple revisions
# Upstream status: backport
#
# 2017-09-05 jsmoeller@linuxfoundation.org
From 87bd4186da10371f46e2f1a7bf7c0a45bb04f1ac Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Mon, 19 Jun 2017 18:33:26 +0200
Subject: [PATCH] CVE-2017-1000366: Ignore LD_LIBRARY_PATH for AT_SECURE=1
programs [BZ #21624]
LD_LIBRARY_PATH can only be used to reorder system search paths, which
is not useful functionality.
This makes an exploitable unbounded alloca in _dl_init_paths unreachable
for AT_SECURE=1 programs.
(cherry picked from commit f6110a8fee2ca36f8e2d2abecf3cba9fa7b8ea7d)
---
ChangeLog | 7 +++++++
NEWS | 1 +
elf/rtld.c | 3 ++-
3 files changed, 10 insertions(+), 1 deletion(-)
# removed to apply on older version ...
#
#diff --git a/ChangeLog b/ChangeLog
#index 1795e28..e37f14f 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,3 +1,10 @@
#+2017-06-19 Florian Weimer <fweimer@redhat.com>
#+
#+ [BZ #21624]
#+ CVE-2017-1000366
#+ * elf/rtld.c (process_envvars): Ignore LD_LIBRARY_PATH for
#+ __libc_enable_secure.
#+
# 2017-02-01 Andreas Schwab <schwab@linux-m68k.org>
#
# * sysdeps/m68k/m680x0/m68020/atomic-machine.h
#diff --git a/NEWS b/NEWS
#index 82a718f..d42af91 100644
#--- a/NEWS
#+++ b/NEWS
#@@ -25,6 +25,7 @@ The following bugs are resolved with this release:
#
# [21289] Fix symbol redirect for fts_set
# [21386] Assertion in fork for distinct parent PID is incorrect
#+ [21624] Unsafe alloca allows local attackers to alias stack and heap (CVE-2017-1000366)
#
# Version 2.24
#
diff --git a/elf/rtld.c b/elf/rtld.c
index 647661c..215a9ae 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -2437,7 +2437,8 @@ process_envvars (enum mode *modep)
case 12:
/* The library search path. */
- if (memcmp (envline, "LIBRARY_PATH", 12) == 0)
+ if (!__libc_enable_secure
+ && memcmp (envline, "LIBRARY_PATH", 12) == 0)
{
library_path = &envline[13];
break;
--
2.9.3
|
