# New Ticket Created by Brian Candler # Please include the string: [perl #37230] # in the subject line of all future correspondence about this issue. # <URL: https://rt.perl.org/rt3/Ticket/Display.html?id=37230 >
Summary: regular expression overflows stack in 5.8.7 (but same test case
works in 5.8.6).
A program which replicates this problem is attached, as a gzip file to
prevent it being split by E-mail, as it contains one very long line (~32K)
Output of perl -v, perl -V and perlbug -d on the target system is also
attached.
The regular expression is:
^"(?:[^"\\]|\\.)*"\s+\d+\s+(\d+)
(aside: it is used to parse a double-quoted string in an Apache log file; if
the string contains a double quote it appears as \" and if it contains a
backslash it appears as \\)
It was a real Apache log entry which made Perl bomb out, and this is what
the attached test program contains.
I don't see any reason for deep recursion in this regexp: at each stage it
has two options to match, { any character other than " or \ } or
{ \ followed by any character }, and if it cannot chomp one or the other
then the regexp should fail. If it _can_ match either of those then there is
no ambiguity and possibility of backtracking, as far as I can see.
Regards,
Brian Candler.
chomplogs-test2.pl.gz
Description: application/gunzip
-bash-2.05b$ perl -v This is perl, v5.8.7 built for i386-freebsd-64int (with 1 registered patch, see perl -V for more detail) Copyright 1987-2005, Larry Wall Perl may be copied only under the terms of either the Artistic License or the GNU General Public License, which may be found in the Perl 5 source kit. Complete documentation for Perl, including FAQ lists, should be found on this system using `man perl' or `perldoc perl'. If you have access to the Internet, point your browser at http://www.perl.org/, the Perl Home Page. -bash-2.05b$ perl -V Summary of my perl5 (revision 5 version 8 subversion 7) configuration: Platform: osname=freebsd, osvers=4.11-release, archname=i386-freebsd-64int uname='freebsd ch-adm01.uk.clara.net 4.11-release freebsd 4.11-release #0: fri jan 21 17:21:22 gmt 2005 [EMAIL PROTECTED]:usrobjusrsrcsysgeneric i386 ' config_args='-sde -Dprefix=/usr/local -Darchlib=/usr/local/lib/perl5/5.8.7/mach -Dprivlib=/usr/local/lib/perl5/5.8.7 -Dman3dir=/usr/local/lib/perl5/5.8.7/perl/man/man3 -Dman1dir=/usr/local/man/man1 -Dsitearch=/usr/local/lib/perl5/site_perl/5.8.7/mach -Dsitelib=/usr/local/lib/perl5/site_perl/5.8.7 -Dscriptdir=/usr/local/bin -Dsiteman3dir=/usr/local/lib/perl5/5.8.7/man/man3 -Dsiteman1dir=/usr/local/man/man1 -Ui_malloc -Ui_iconv -Uinstallusrbinperl -Dcc=cc -Duseshrplib -Dccflags=-DAPPLLIB_EXP="/usr/local/lib/perl5/5.8.7/BSDPAN" -Doptimize=-O -pipe -Ud_dosuid -Ui_gdbm -Dusethreads=n -Dusemymalloc=y -Duse64bitint' hint=recommended, useposix=true, d_sigaction=define usethreads=undef use5005threads=undef useithreads=undef usemultiplicity=undef useperlio=define d_sfio=undef uselargefiles=define usesocks=undef use64bitint=define use64bitall=undef uselongdouble=undef usemymalloc=y, bincompat5005=undef Compiler: cc='cc', ccflags ='-DAPPLLIB_EXP="/usr/local/lib/perl5/5.8.7/BSDPAN" -D_THREAD_SAFE -DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -I/usr/local/include', optimize='-O -pipe ', cppflags='-DAPPLLIB_EXP="/usr/local/lib/perl5/5.8.7/BSDPAN" -D_THREAD_SAFE -DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -I/usr/local/include' ccversion='', gccversion='2.95.4 20020320 [FreeBSD]', gccosandvers='' intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=12345678 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12 ivtype='long long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8 alignbytes=4, prototype=define Linker and Libraries: ld='cc', ldflags ='-pthread -Wl,-E -L/usr/local/lib' libpth=/usr/lib /usr/local/lib libs=-lm -lcrypt -lutil perllibs=-lm -lcrypt -lutil libc=, so=so, useshrplib=true, libperl=libperl.so gnulibc_version='' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' -Wl,-R/usr/local/lib/perl5/5.8.7/mach/CORE' cccdlflags='-DPIC -fPIC', lddlflags='-shared -L/usr/local/lib' Characteristics of this binary (from libperl): Compile-time options: USE_64_BIT_INT USE_LARGE_FILES Locally applied patches: defined-or Built under freebsd Compiled at Sep 8 2005 11:49:14 @INC: /usr/local/lib/perl5/site_perl/5.8.7/mach /usr/local/lib/perl5/site_perl/5.8.7 /usr/local/lib/perl5/site_perl /usr/local/lib/perl5/5.8.7/BSDPAN /usr/local/lib/perl5/5.8.7/mach /usr/local/lib/perl5/5.8.7 . -bash-2.05b$ perlbug -d --- Flags: category= severity= --- Site configuration information for perl v5.8.7: Configured by andym at Thu Sep 8 11:49:00 BST 2005. Summary of my perl5 (revision 5 version 8 subversion 7) configuration: Platform: osname=freebsd, osvers=4.11-release, archname=i386-freebsd-64int uname='freebsd ch-adm01.uk.clara.net 4.11-release freebsd 4.11-release #0: fri jan 21 17:21:22 gmt 2005 [EMAIL PROTECTED]:usrobjusrsrcsysgeneric i386 ' config_args='-sde -Dprefix=/usr/local -Darchlib=/usr/local/lib/perl5/5.8.7/mach -Dprivlib=/usr/local/lib/perl5/5.8.7 -Dman3dir=/usr/local/lib/perl5/5.8.7/perl/man/man3 -Dman1dir=/usr/local/man/man1 -Dsitearch=/usr/local/lib/perl5/site_perl/5.8.7/mach -Dsitelib=/usr/local/lib/perl5/site_perl/5.8.7 -Dscriptdir=/usr/local/bin -Dsiteman3dir=/usr/local/lib/perl5/5.8.7/man/man3 -Dsiteman1dir=/usr/local/man/man1 -Ui_malloc -Ui_iconv -Uinstallusrbinperl -Dcc=cc -Duseshrplib -Dccflags=-DAPPLLIB_EXP="/usr/local/lib/perl5/5.8.7/BSDPAN" -Doptimize=-O -pipe -Ud_dosuid -Ui_gdbm -Dusethreads=n -Dusemymalloc=y -Duse64bitint' hint=recommended, useposix=true, d_sigaction=define usethreads=undef use5005threads=undef useithreads=undef usemultiplicity=undef useperlio=define d_sfio=undef uselargefiles=define usesocks=undef use64bitint=define use64bitall=undef uselongdouble=undef usemymalloc=y, bincompat5005=undef Compiler: cc='cc', ccflags ='-DAPPLLIB_EXP="/usr/local/lib/perl5/5.8.7/BSDPAN" -D_THREAD_SAFE -DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -I/usr/local/include', optimize='-O -pipe ', cppflags='-DAPPLLIB_EXP="/usr/local/lib/perl5/5.8.7/BSDPAN" -D_THREAD_SAFE -DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -I/usr/local/include' ccversion='', gccversion='2.95.4 20020320 [FreeBSD]', gccosandvers='' intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=12345678 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12 ivtype='long long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8 alignbytes=4, prototype=define Linker and Libraries: ld='cc', ldflags ='-pthread -Wl,-E -L/usr/local/lib' libpth=/usr/lib /usr/local/lib libs=-lm -lcrypt -lutil perllibs=-lm -lcrypt -lutil libc=, so=so, useshrplib=true, libperl=libperl.so gnulibc_version='' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' -Wl,-R/usr/local/lib/perl5/5.8.7/mach/CORE' cccdlflags='-DPIC -fPIC', lddlflags='-shared -L/usr/local/lib' Locally applied patches: defined-or --- @INC for perl v5.8.7: /usr/local/lib/perl5/site_perl/5.8.7 /usr/local/lib/perl5/site_perl/5.8.7/mach /usr/local/lib/perl5/site_perl /usr/local/lib/perl5/5.8.7/BSDPAN /usr/local/lib/perl5/5.8.7/mach /usr/local/lib/perl5/5.8.7 . --- Environment for perl v5.8.7: HOME=/home/brian LANG (unset) LANGUAGE (unset) LD_LIBRARY_PATH (unset) LOGDIR (unset) PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/games:/usr/local/sbin:/usr/local/bin:/usr/X11R6/bin:/home/brian/bin PERL_BADLANG (unset) SHELL=/bin/bash
