main/grep: security fix for CVE-2015-1345

ref #3864

1 files changed, 138 insertions, 0 deletions

diff --git a/main/grep/CVE-2015-1345.patch b/main/grep/CVE-2015-1345.patch
new file mode 100644
index 0000000000..2e2f59df42
--- /dev/null
+++ b/main/grep/CVE-2015-1345.patch
@@ -0,0 +1,138 @@
+From 83a95bd8c8561875b948cadd417c653dbe7ef2e2 Mon Sep 17 00:00:00 2001
+From: Yuliy Pisetsky <ypisetsky@fb.com>
+Date: Thu, 01 Jan 2015 23:36:55 +0000
+Subject: grep -F: fix a heap buffer (read) overrun
+
+grep's read buffer is often filled to its full size, except when
+reading the final buffer of a file.  In that case, the number of
+bytes read may be far less than the size of the buffer.  However, for
+certain unusual pattern/text combinations, grep -F would mistakenly
+examine bytes in that uninitialized region of memory when searching
+for a match.  With carefully chosen inputs, one can cause grep -F to
+read beyond the end of that buffer altogether.  This problem arose via
+commit v2.18-90-g73893ff with the introduction of a more efficient
+heuristic using what is now the memchr_kwset function. The use of
+that function in bmexec_trans could leave TP much larger than EP,
+and the subsequent call to bm_delta2_search would mistakenly access
+beyond end of the main input read buffer.
+
+* src/kwset.c (bmexec_trans): When TP reaches or exceeds EP,
+do not call bm_delta2_search.
+* tests/kwset-abuse: New file.
+* tests/Makefile.am (TESTS): Add it.
+* THANKS.in: Update.
+* NEWS (Bug fixes): Mention it.
+
+Prior to this patch, this command would trigger a UMR:
+
+  printf %0360db 0 | valgrind src/grep -F $(printf %019dXb 0)
+
+  Use of uninitialised value of size 8
+     at 0x4142BE: bmexec_trans (kwset.c:657)
+     by 0x4143CA: bmexec (kwset.c:678)
+     by 0x414973: kwsexec (kwset.c:848)
+     by 0x414DC4: Fexecute (kwsearch.c:128)
+     by 0x404E2E: grepbuf (grep.c:1238)
+     by 0x4054BF: grep (grep.c:1417)
+     by 0x405CEB: grepdesc (grep.c:1645)
+     by 0x405EC1: grep_command_line_arg (grep.c:1692)
+     by 0x4077D4: main (grep.c:2570)
+
+See the accompanying test for how to trigger the heap buffer overrun.
+
+Thanks to Nima Aghdaii for testing and finding numerous
+ways to break early iterations of this patch.
+---
+diff --git a/NEWS b/NEWS
+index 975440d..3835d8d 100644
+--- a/NEWS
++++ b/NEWS
+@@ -2,6 +2,11 @@ GNU grep NEWS                                    -*- outline -*-
+ 
+ * Noteworthy changes in release ?.? (????-??-??) [?]
+ 
++** Bug fixes
++
++  grep no longer reads from uninitialized memory or from beyond the end
++  of the heap-allocated input buffer.
++
+ 
+ * Noteworthy changes in release 2.21 (2014-11-23) [stable]
+ 
+diff --git a/THANKS.in b/THANKS.in
+index aeaf516..624478d 100644
+--- a/THANKS.in
++++ b/THANKS.in
+@@ -62,6 +62,7 @@ Michael Aichlmayr                   mikla@nx.com
+ Miles Bader                         miles@ccs.mt.nec.co.jp
+ Mirraz Mirraz                       mirraz1@rambler.ru
+ Nelson H. F. Beebe                  beebe@math.utah.edu
++Nima Aghdaii                        naghdaii@fb.com
+ Olaf Kirch                          okir@ns.lst.de
+ Paul Kimoto                         kimoto@spacenet.tn.cornell.edu
+ Péter Radics                        mitchnull@gmail.com
+diff --git a/src/kwset.c b/src/kwset.c
+index 4003c8d..376f7c3 100644
+--- a/src/kwset.c
++++ b/src/kwset.c
+@@ -643,6 +643,8 @@ bmexec_trans (kwset_t kwset, char const *text, size_t size)
+                     if (! tp)
+                       return -1;
+                     tp++;
++                    if (ep <= tp)
++                      break;
+                   }
+               }
+           }
+diff --git a/tests/Makefile.am b/tests/Makefile.am
+index 2cba2cd..0508cd2 100644
+--- a/tests/Makefile.am
++++ b/tests/Makefile.am
+@@ -75,6 +75,7 @@ TESTS =						\
+   inconsistent-range				\
+   invalid-multibyte-infloop			\
+   khadafy					\
++  kwset-abuse					\
+   long-line-vs-2GiB-read			\
+   match-lines					\
+   max-count-overread				\
+diff --git a/tests/kwset-abuse b/tests/kwset-abuse
+new file mode 100755
+index 0000000..6d8ec0c
+--- a/dev/null
++++ b/tests/kwset-abuse
+@@ -0,0 +1,32 @@
++#! /bin/sh
++# Evoke a segfault in a hard-to-reach code path of kwset.c.
++# This bug affected grep versions 2.19 through 2.21.
++#
++# Copyright (C) 2015 Free Software Foundation, Inc.
++#
++# This program is free software: you can redistribute it and/or modify
++# it under the terms of the GNU General Public License as published by
++# the Free Software Foundation, either version 3 of the License, or
++# (at your option) any later version.
++
++# This program is distributed in the hope that it will be useful,
++# but WITHOUT ANY WARRANTY; without even the implied warranty of
++# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++# GNU General Public License for more details.
++
++# You should have received a copy of the GNU General Public License
++# along with this program.  If not, see <http://www.gnu.org/licenses/>.
++
++. "${srcdir=.}/init.sh"; path_prepend_ ../src
++
++fail=0
++
++# This test case chooses a haystack of size 260,000, since prodding
++# with gdb showed a reallocation slightly larger than that in fillbuf.
++# To reach the buggy code, the needle must have length < 1/11 that of
++# the haystack, and 10,000 is a nice round number that fits the bill.
++printf '%0260000dXy\n' 0 | grep -F $(printf %010000dy 0)
++
++test $? = 1 || fail=1
++
++Exit $fail
+--
+cgit v0.9.0.2