Bug in tracing in DBD::Oracle

Hi,

I was asked to enable ora_verbose and send a trace a few days ago.

I'm getting a segfault with DBD::Oracle when ora_verbose or dbd_verbose
is set to 15 in the connect method call. The stack trace is:

(gdb) bt
#0  0x080be45c in Perl_sv_vcatpvfn ()
#1  0x080ccd6d in Perl_vnewSVpvf ()
#2  0x0811cb54 in PerlIO_vprintf ()
#3  0x0811cbdf in PerlIO_printf ()
#4  0x007e961c in ora_db_login6 (dbh=0x830f6a0, imp_dbh=0x834b0b0,
dbname=<value optimised out>, uid=0x81aedf8 "bet",
    pwd=0x81aee08 "b3t", attr=0x830ee20) at dbdimp.c:546
#5  0x007dd0e0 in XS_DBD__Oracle__db__login (my_perl=0x8188008,
cv=0x8344b88) at ./Oracle.xsi:100
#6  0x080b12c0 in Perl_pp_entersub ()
#7  0x080af688 in Perl_runops_standard ()
#8  0x080acf4b in Perl_call_sv ()
#9  0x00575f0a in XS_DBI_dispatch (my_perl=0x8188008, cv=0x82bfa88) at
DBI.xs:3442
#10 0x080b12c0 in Perl_pp_entersub ()
#11 0x080af688 in Perl_runops_standard ()
#12 0x080adbb2 in perl_run ()
#13 0x08063ffd in main ()

and that refers to the following line in dbdimp.c:

OCINlsEnvironmentVariableGet_log_stat( &ncharsetid,(size_t)  0,
OCI_NLS_NCHARSET_ID, 0, &rsize ,status );

Oracle defines the second argument as size_t so I guess that cast of 0
to size_t is ok but ocitrace.h then goes on to cast it again to
(unsigned long long) and the format argument has been changed to %llu.
Although these match it segfaults.

This segfaults on my Linux machine described with the Perl -V output
below. I cannot believe the size of the first argument passed to
OCINlsEnvironmentVariableGet is every going to need a size_t and in any
case it has a max size of OCI_NLS_MAXBUFSZ (100 in Instant Client 11.1
for Linux X86).

I imagine this got changed by someone with a 64 bit system where size_t
was possibly unsigned long long and that generated a warning on the call
to PerlIO_printf.

I changed my version to remove the cast to size_t from the call to
OCINlsEnvironmentVariableGet and put this cast in the real call in the
macro instead. I then changed the format for the size in the
PerlIO_printf to %lu and cast to (unsigned long)

I believe this should work for 64bit machines too since
OCINlsEnvironmentVariableGet is only currently used for integer types
and not string types so all the calls pass 0 anyway. Perhaps someone who
has a 64bit machine could check this out.

Summary of my perl5 (revision 5 version 10 subversion 0) configuration:
  Platform:
    osname=linux, osvers=2.6.24-23-server,
archname=i486-linux-gnu-thread-multi
    uname='linux vernadsky 2.6.24-23-server #1 smp wed apr 1 22:22:14
utc 2009 i686 gnulinux '
    config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN
-Dcccdlflags=-fPIC -Darchname=i486-linux-gnu -Dprefix=/usr
-Dprivlib=/usr/share/perl/5.10 -Darchlib=/usr/lib/perl/5.10
-Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5
-Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local
-Dsitelib=/usr/local/share/perl/5.10.0
-Dsitearch=/usr/local/lib/perl/5.10.0 -Dman1dir=/usr/share/man/man1
-Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1
-Dsiteman3dir=/usr/local/man/man3 -Dman1ext=1 -Dman3ext=3perl
-Dpager=/usr/bin/sensible-pager -Uafs -Ud_csh -Ud_ualarm -Uusesfio
-Uusenm -DDEBUGGING=-g -Doptimize=-O2 -Duseshrplib
-Dlibperl=libperl.so.5.10.0 -Dd_dosuid -des'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=define, usemultiplicity=define
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=undef, use64bitall=undef, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN
-fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE
-D_FILE_OFFSET_BITS=64',
    optimize='-O2 -g',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fno-strict-aliasing
-pipe -I/usr/local/include'
    ccversion='', gccversion='4.4.1', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=8
    alignbytes=4, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib /usr/lib64
    libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc -lcrypt
    perllibs=-ldl -lm -lpthread -lc -lcrypt
    libc=/lib/libc-2.10.1.so, so=so, useshrplib=true,
libperl=libperl.so.5.10.0
    gnulibc_version='2.10.1'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -g -L/usr/local/lib'


Characteristics of this binary (from libperl):
  Compile-time options: MULTIPLICITY PERL_DONT_CREATE_GVSV
                        PERL_IMPLICIT_CONTEXT PERL_MALLOC_WRAP USE_ITHREADS
                        USE_LARGE_FILES USE_PERLIO USE_REENTRANT_API
  Built under linux
  Compiled at Oct  1 2009 22:19:26
  %ENV:
    PERL5LIB="/home/martin/xxx/tools/modules/XXX/lib:/home/martin/xxx/cgi"
  @INC:
    /home/martin/xxx/tools/modules/XXX/lib
    /home/martin/xxx/cgi
    /etc/perl
    /usr/local/lib/perl/5.10.0
    /usr/local/share/perl/5.10.0
    /usr/lib/perl5
    /usr/share/perl5
    /usr/lib/perl/5.10
    /usr/share/perl/5.10
    /usr/local/lib/site_perl
    .

Martin
-- 
Martin J. Evans
Easysoft Limited
http://www.easysoft.com