#40894 [NEW]: fix for bug #38770 causes more harm than good on big-endian 64bit
From: mmarek at suse dot cz
Operating system:
PHP version: 5.2.1
PHP Bug Type: *Programming Data Structures
Bug description: fix for bug #38770 causes more harm than good on big-endian 64bit
Description:
------------
Fix for bug #38770 breaks unpack() on big-endian 64bit, because it reads
uninitialized memory or memory that doesn't relate to the data being
processed.
In
http://cvs.php.net/viewvc.cgi/php-src/ext/standard/pack.c?r1=1.62&r2=1.63
input[inputpos + machine_endian_long_map[3]] will read input[inputpos+7]
when unpacking 4 bytes.
Please revert the fix, as it tries to fix a questionable issue (-30000
simply doesn't fit into unsigned type) and causes trouble in cases where it
worked before (eg. pear is not even installable on POWER, b/c
install-pear-nozlib.phar makes heavy use of unpack()).
Reproduce code:
---------------
run
print_r( unpack( "V", pack( "V", 200 ) ));
several times on ppc64.
Expected result:
----------------
It should output
Array
(
[1] => 200
)
all the time.
Actual result:
--------------
# ./sapi/cli/php -r 'print_r( unpack( "V", pack( "V", 200 ) ));'
Array
(
[1] => 200
)
# ./sapi/cli/php -r 'print_r( unpack( "V", pack( "V", 200 ) ));'
Array
(
[1] => -2147483448
)
# ./sapi/cli/php -r 'print_r( unpack( "V", pack( "V", 200 ) ));'
Array
(
[1] => 200
)
# ./sapi/cli/php -r 'print_r( unpack( "V", pack( "V", 200 ) ));'
Array
(
[1] => 200
)
# ./sapi/cli/php -r 'print_r( unpack( "V", pack( "V", 200 ) ));'
Array
(
[1] => -2147483448
)
--
Edit bug report at http://bugs.php.net/?id=40894&edit=1
--
Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=40894&r=trysnapshot44
Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=40894&r=trysnapshot52
Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=40894&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=40894&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=40894&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=40894&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=40894&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=40894&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=40894&r=support
Expected behavior: http://bugs.php.net/fix.php?id=40894&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=40894&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=40894&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=40894&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=40894&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=40894&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=40894&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=40894&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=40894&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=40894&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=40894&r=mysqlcfg
Thread (3 messages)
- mmarek at suse dot cz