Submitted By: Robert Connolly <robert at linuxfromscratch dot org> (ashes)
Date: 2010-02-24
Initial Package Version: 5.10.1
Upstream Status: From upstream
Origin: Git
http://perl5.git.perl.org/perl.git/patch/0abd0d78a73da1c4d13b1c700526b7e5d03b32d4
Description: Bug fix for invalid utf-8 characters causing Perl to crash.

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3626

From 0abd0d78a73da1c4d13b1c700526b7e5d03b32d4 Mon Sep 17 00:00:00 2001
From: Yves Orton <demerphq@gmail.com>
Date: Sun, 25 Oct 2009 20:37:08 +0100
Subject: [PATCH] disable non-unicode case insensitive trie matching

Also revert 8902bb05b18c9858efa90229ca1ee42b17277554 as it merely
masked one symptom of the deeper problems.

Also fixes RT #69973, which was a segfault which was exposed by
8902bb05, see the ticket for further details.

http://rt.perl.org/rt3//Public/Bug/Display.html?id=69973

At the code of this is the problem that in unicode matching a bunch
of code points have case folding rules beyond just A-Z/a-z. Since
the case folding rules are decided at runtime by the string, we cant
use the same TRIE tables for both unicode/non-unicode matching.

Until this is reconciled or some other solution is found case insensitive
matching only gets the TRIE optimisation when the pattern is uniocde.

From CaseFolding.txt:

00B5; C; 03BC; # MICRO SIGN
00C0; C; 00E0; # LATIN CAPITAL LETTER A WITH GRAVE
00C1; C; 00E1; # LATIN CAPITAL LETTER A WITH ACUTE
00C2; C; 00E2; # LATIN CAPITAL LETTER A WITH CIRCUMFLEX
00C3; C; 00E3; # LATIN CAPITAL LETTER A WITH TILDE
00C4; C; 00E4; # LATIN CAPITAL LETTER A WITH DIAERESIS
00C5; C; 00E5; # LATIN CAPITAL LETTER A WITH RING ABOVE
00C6; C; 00E6; # LATIN CAPITAL LETTER AE
00C7; C; 00E7; # LATIN CAPITAL LETTER C WITH CEDILLA
00C8; C; 00E8; # LATIN CAPITAL LETTER E WITH GRAVE
00C9; C; 00E9; # LATIN CAPITAL LETTER E WITH ACUTE
00CA; C; 00EA; # LATIN CAPITAL LETTER E WITH CIRCUMFLEX
00CB; C; 00EB; # LATIN CAPITAL LETTER E WITH DIAERESIS
00CC; C; 00EC; # LATIN CAPITAL LETTER I WITH GRAVE
00CD; C; 00ED; # LATIN CAPITAL LETTER I WITH ACUTE
00CE; C; 00EE; # LATIN CAPITAL LETTER I WITH CIRCUMFLEX
00CF; C; 00EF; # LATIN CAPITAL LETTER I WITH DIAERESIS
00D0; C; 00F0; # LATIN CAPITAL LETTER ETH
00D1; C; 00F1; # LATIN CAPITAL LETTER N WITH TILDE
00D2; C; 00F2; # LATIN CAPITAL LETTER O WITH GRAVE
00D3; C; 00F3; # LATIN CAPITAL LETTER O WITH ACUTE
00D4; C; 00F4; # LATIN CAPITAL LETTER O WITH CIRCUMFLEX
00D5; C; 00F5; # LATIN CAPITAL LETTER O WITH TILDE
00D6; C; 00F6; # LATIN CAPITAL LETTER O WITH DIAERESIS
00D8; C; 00F8; # LATIN CAPITAL LETTER O WITH STROKE
00D9; C; 00F9; # LATIN CAPITAL LETTER U WITH GRAVE
00DA; C; 00FA; # LATIN CAPITAL LETTER U WITH ACUTE
00DB; C; 00FB; # LATIN CAPITAL LETTER U WITH CIRCUMFLEX
00DC; C; 00FC; # LATIN CAPITAL LETTER U WITH DIAERESIS
00DD; C; 00FD; # LATIN CAPITAL LETTER Y WITH ACUTE
00DE; C; 00FE; # LATIN CAPITAL LETTER THORN
00DF; F; 0073 0073; # LATIN SMALL LETTER SHARP S
---
 ext/re/t/regop.t |   12 ++++++------
 regcomp.c        |   17 +++++++++++------
 regexec.c        |    9 ++-------
 3 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/ext/re/t/regop.t b/ext/re/t/regop.t
index 9118bf6..46e6ec0 100644
--- ext/re/t/regop.t
+++ ext/re/t/regop.t
@@ -231,12 +231,12 @@ anchored "ABC" at 0
 #Freeing REx: "(\\.COM|\\.EXE|\\.BAT|\\.CMD|\\.VBS|\\.VBE|\\.JS|\\.JSE|\\."......
 %MATCHED%
 floating ""$ at 3..4 (checking floating)
-1:1[1] 3:2[1] 5:2[64] 45:83[1] 47:84[1] 48:85[0]
-stclass EXACTF <.> minlen 3
-Found floating substr ""$ at offset 30...
-Does not contradict STCLASS...
-Guessed: match at offset 26
-Matching stclass EXACTF <.> against ".exe"
+#1:1[1] 3:2[1] 5:2[64] 45:83[1] 47:84[1] 48:85[0]
+#stclass EXACTF <.> minlen 3
+#Found floating substr ""$ at offset 30...
+#Does not contradict STCLASS...
+#Guessed: match at offset 26
+#Matching stclass EXACTF <.> against ".exe"
 ---
 #Compiling REx "[q]"
 #size 12 nodes Got 100 bytes for offset annotations.
diff --git a/regcomp.c b/regcomp.c
index 6e9fa26..eb5f12f 100644
--- regcomp.c
+++ regcomp.c
@@ -2833,13 +2833,18 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                                 }
                             } else {
 /* 
-    Currently we assume that the trie can handle unicode and ascii
-    matches fold cased matches. If this proves true then the following
-    define will prevent tries in this situation. 
-    
-    #define TRIE_TYPE_IS_SAFE (UTF || optype==EXACT)
-*/
+    Currently we do not believe that the trie logic can
+    handle case insensitive matching properly when the
+    pattern is not unicode (thus forcing unicode semantics).
+
+    If/when this is fixed the following define can be swapped
+    in below to fully enable trie logic.
+
 #define TRIE_TYPE_IS_SAFE 1
+
+*/
+#define TRIE_TYPE_IS_SAFE (UTF || optype==EXACT)
+
                                 if ( last && TRIE_TYPE_IS_SAFE ) {
                                     make_trie( pRExC_state, 
                                             startbranch, first, cur, tail, count, 
diff --git a/regexec.c b/regexec.c
index 402ede3..ec09c28 100644
--- regexec.c
+++ regexec.c
@@ -1105,16 +1105,15 @@ Perl_re_intuit_start(pTHX_ REGEXP * const rx, SV *sv, char *strpos,
 
 #define REXEC_TRIE_READ_CHAR(trie_type, trie, widecharmap, uc, uscan, len,  \
 uvc, charid, foldlen, foldbuf, uniflags) STMT_START {                       \
-    UV uvc_unfolded = 0;						    \
     switch (trie_type) {                                                    \
     case trie_utf8_fold:                                                    \
 	if ( foldlen>0 ) {                                                  \
-	    uvc_unfolded = uvc = utf8n_to_uvuni( uscan, UTF8_MAXLEN, &len, uniflags ); \
+	    uvc = utf8n_to_uvuni( uscan, UTF8_MAXLEN, &len, uniflags ); \
 	    foldlen -= len;                                                 \
 	    uscan += len;                                                   \
 	    len=0;                                                          \
 	} else {                                                            \
-	    uvc_unfolded = uvc = utf8n_to_uvuni( (U8*)uc, UTF8_MAXLEN, &len, uniflags ); \
+	    uvc = utf8n_to_uvuni( (U8*)uc, UTF8_MAXLEN, &len, uniflags ); \
 	    uvc = to_uni_fold( uvc, foldbuf, &foldlen );                    \
 	    foldlen -= UNISKIP( uvc );                                      \
 	    uscan = foldbuf + UNISKIP( uvc );                               \
@@ -1140,7 +1139,6 @@ uvc, charid, foldlen, foldbuf, uniflags) STMT_START {                       \
 	uvc = (UV)*uc;                                                      \
 	len = 1;                                                            \
     }                                                                       \
-									    \
     if (uvc < 256) {                                                        \
 	charid = trie->charmap[ uvc ];                                      \
     }                                                                       \
@@ -1153,9 +1151,6 @@ uvc, charid, foldlen, foldbuf, uniflags) STMT_START {                       \
 		charid = (U16)SvIV(*svpp);                                  \
 	}                                                                   \
     }                                                                       \
-    if (!charid && trie_type == trie_utf8_fold && !UTF) {		    \
-	charid = trie->charmap[uvc_unfolded];			    	    \
-    }								    	    \
 } STMT_END
 
 #define REXEC_FBC_EXACTISH_CHECK(CoNd)                 \
-- 
1.6.5.2.74.g610f9.dirty

