From: wccoder at gmail dot com
Operating system: Fedora Core 7, x64
PHP version: 5.2.5
PHP Bug Type: GD related
Bug description: DoS (segfault) in libgd TTF processing
Description:
------------
ext/gd/libgd/gdft.c:950
if (font->face->charmap->encoding == FT_ENCODING_MS_SYMBOL &&
strcmp(font->face->family_name, "Symbol") == 0) {
A crafted .ttf file with a null font->face->family_name causes strcmp to
attempt to access memory out of bounds and cores. I have a sample .ttf file
I can send.
Reproduce code:
---------------
<?php
$size = imagettfbbox(10, 0, 'crafted_font.ttf', 'steve');
?>
Expected result:
----------------
The php process cores.
Actual result:
--------------
#0 0x000000356c876bd0 in strcmp () from /lib64/libc.so.6
#1 0x00000000004bc5b3 in php_gd_gdImageStringFTEx (im=0x0,
brect=0x7fffbce07cc0, fg=-1, fontlist=0xba5b80 "shifter_3042_4.ttf",
ptsize=10, angle=0, x=-1, y=-1, string=0xba8fb8 "steve", strex=0x0) at
/home/wccoder/build/php-5.2.5/ext/gd/libgd/gdft.c:953
#2 0x00000000004bbe2b in php_gd_gdImageStringFT (im=0x0,
brect=0x7fffbce07cc0, fg=-1, fontlist=0xba5b80 "shifter_3042_4.ttf",
ptsize=10, angle=0, x=-1, y=-1, string=0xba8fb8 "steve") at
/home/wccoder/build/php-5.2.5/ext/gd/libgd/gdft.c:769
#3 0x00000000004a3d44 in php_imagettftext_common (ht=<value optimized
out>, return_value=0xba73f8,
return_value_ptr=<value optimized out>, this_ptr=<value optimized
out>, return_value_used=<value optimized out>,
mode=<value optimized out>, extended=0) at
/home/wccoder/build/php-5.2.5/ext/gd/gd.c:4303
#4 0x00000000004a3de6 in zif_imagettfbbox (ht=0, return_value=0x740fa0,
return_value_ptr=0x7fffbce077d0, this_ptr=0x356cb4b760,
return_value_used=-1) at
/home/wccoder/build/php-5.2.5/ext/gd/gd.c:4199
#5 0x0000000000665f1b in zend_do_fcall_common_helper_SPEC
(execute_data=0x7fffbce07f40)
at /home/wccoder/build/php-5.2.5/Zend/zend_vm_execute.h:200
#6 0x0000000000665013 in execute (op_array=0xba6d58) at
/home/wccoder/build/php-5.2.5/Zend/zend_vm_execute.h:92
#7 0x0000000000647013 in zend_execute_scripts (type=8, retval=0xbd8f80,
file_count=3)
at /home/wccoder/build/php-5.2.5/Zend/zend.c:1134
#8 0x000000000060776b in php_execute_script (primary_file=0x7fffbce0a5b0)
at /home/wccoder/build/php-5.2.5/main/main.c:2004
#9 0x00000000006c1e42 in main (argc=3, argv=0x7fffbce0a7b8) at
/home/wccoder/build/php-5.2.5/sapi/cli/php_cli.c:1140
--
Edit bug report at http://bugs.php.net/?id=43790&edit=1
--
Try a CVS snapshot (PHP 4.4):
http://bugs.php.net/fix.php?id=43790&r=trysnapshot44
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=43790&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=43790&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=43790&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=43790&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=43790&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=43790&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=43790&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=43790&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=43790&r=support
Expected behavior: http://bugs.php.net/fix.php?id=43790&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=43790&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=43790&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=43790&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=43790&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=43790&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=43790&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=43790&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=43790&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=43790&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=43790&r=mysqlcfg
