# 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 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 #+ #+ [BZ #21624] #+ CVE-2017-1000366 #+ * elf/rtld.c (process_envvars): Ignore LD_LIBRARY_PATH for #+ __libc_enable_secure. #+ # 2017-02-01 Andreas Schwab # # * 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