ID: 29944
Comment by: dmhouse at gmail dot com
Reported By: norxh at binnews dot com
Status: Assigned
Bug Type: Reproducible crash
Operating System: *
PHP Version: 5CVS-2005-03-07
Assigned To: andi
New Comment:
I have a reduced test case for this bug.
<?php
$foo = 'bar';
switch ($foo) {
case 'bar':
function foobar() {
$variable = 1;
}
foobar();
break;
}
?>
Things necessary for Apache to segfault:
* The function must be defined inside a case statement that is
executed.
* A variable must be set to a value within the function.
* The function must be called.
I'm running PHP 5.0.3 (built from source, but I doubt that matters) on
Apache 2. Bug is reproducible through Apache and through CLI.
Previous Comments:
------------------------------------------------------------------------
[2005-03-04 15:17:24] kameshj at fastmail dot fm
Problem is in CG(switch_cond_stack) that is shared by two op_arrays(One
which has original switch and another one being the function declararion
inside a case).
Case 1
----------------
<?php
function foo()
{
echo "hi";
}
?>
op_array of foo
ZEND_ECHO
ZEND_FETCH_CONSTANT
ZEND_RETURN
ZEND_HANDLE_EXCEPTION
Case 2(Segfault case)
----------------
<?php
$a=1;
switch($a)
{
case 1:
function foo()
{
echo "hi";
}
}
?>
op_array of foo
ZEND_ECHO
ZEND_FETCH_CONSTANT
ZEND_SWITCH_FREE
ZEND_RETURN
ZEND_HANDLE_EXCEPTION
In Case 2
ZEND_SWITCH_FREE opcode is getting included in the function foo's
op_array.
This is done by zend_do_return in zend_compile.c with the following
code
zend_stack_apply(&CG(switch_cond_stack), ZEND_STACK_APPLY_TOPDOWN, (int
(*)(void *element)) generate_free_switch_expr);
In zend_do_return of foo of Case 2,
While executing zend_stack_apply,
CG(switch_cond_stack) has 2 entries as follows,
foo's seperator dummy switch_cond(at top)
main op_array's switch case(at bottom)
"main op_array's switch case(at bottom)" is generating ZEND_SWITCH_FREE
opcode.
I feel the switch_cond_stack to be op_array specific rather than
keeping it at compiler_globals as it is now.
------------------------------------------------------------------------
[2004-12-16 21:18:18] edwin at phpfreakz dot nl
I didn't have any problems with declaring functions in a switch
statement with Apache 2/PHP 5.0.1, but after installing PHP 5.0.3 php
crashes. You don't get any errors, it just doesn't work.
I'm using Windows XP Pro with SP2.
------------------------------------------------------------------------
[2004-11-10 15:53:24] sami at sipponen dot com
<?
switch ($_GET["test"]) {
default:
function testfunc() {
}
}
testfunc();
?>
This code crashes PHP 5.1.0-DEV Windows Version.
------------------------------------------------------------------------
[2004-09-02 08:36:55] [EMAIL PROTECTED]
This is only a problem in PHP 5.0.x (and not PHP 5.1.x-dev).
------------------------------------------------------------------------
[2004-09-02 08:32:23] [EMAIL PROTECTED]
Although I see no point in doing this at all (it should not necessarily
work), it shouldn't crash either.
valgrind:
==2720== Conditional jump or move depends on uninitialised value(s)
==2720== at 0x83062CB: zend_switch_free (zend_execute.c:200)
==2720== by 0x8302A8D: zend_switch_free_handler
(zend_execute.c:3222)
==2720== by 0x82FDC88: execute (zend_execute.c:1391)
==2720== by 0x830140F: zend_do_fcall_common_helper
(zend_execute.c:2728)
==2720== by 0x8301890: zend_do_fcall_by_name_handler
(zend_execute.c:2810)
==2720==
==2720== Use of uninitialised value of size 4
==2720== at 0x8305E29: zend_pzval_unlock_func (zend_execute.c:65)
==2720== by 0x83062E6: zend_switch_free (zend_execute.c:205)
==2720== by 0x8302A8D: zend_switch_free_handler
(zend_execute.c:3222)
==2720== by 0x82FDC88: execute (zend_execute.c:1391)
==2720== by 0x830140F: zend_do_fcall_common_helper
(zend_execute.c:2728)
==2720==
==2720== Invalid read of size 4
==2720== at 0x8305E29: zend_pzval_unlock_func (zend_execute.c:65)
==2720== by 0x83062E6: zend_switch_free (zend_execute.c:205)
==2720== by 0x8302A8D: zend_switch_free_handler
(zend_execute.c:3222)
==2720== by 0x82FDC88: execute (zend_execute.c:1391)
==2720== by 0x830140F: zend_do_fcall_common_helper
(zend_execute.c:2728)
==2720== Address 0x8 is not stack'd, malloc'd or (recently) free'd
==2720==
==2720== Process terminating with default action of signal 11
(SIGSEGV)
==2720== Access not within mapped region at address 0x8
==2720== at 0x8305E29: zend_pzval_unlock_func (zend_execute.c:65)
==2720== by 0x83062E6: zend_switch_free (zend_execute.c:205)
==2720== by 0x8302A8D: zend_switch_free_handler
(zend_execute.c:3222)
==2720== by 0x82FDC88: execute (zend_execute.c:1391)
==2720== by 0x830140F: zend_do_fcall_common_helper
(zend_execute.c:2728)
==2720==
GDB:
0x08305e29 in zend_pzval_unlock_func (z=0x0)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:65
65 z->refcount--;
(gdb) bt
#0 0x08305e29 in zend_pzval_unlock_func (z=0x0)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:65
#1 0x083062e7 in zend_switch_free (opline=0x85bd95c, Ts=0x85bdfbc)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:205
#2 0x08302a8e in zend_switch_free_handler (execute_data=0xbfffd400,
opline=0x85bd95c, op_array=0x85bded8)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:3222
#3 0x082fdc89 in execute (op_array=0x85bded8)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:1391
#4 0x08301410 in zend_do_fcall_common_helper
(execute_data=0xbfffd4f0,
opline=0x85bc4cc, op_array=0x85b7f5c)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:2728
#5 0x08301891 in zend_do_fcall_by_name_handler
(execute_data=0xbfffd4f0,
opline=0x85bc4cc, op_array=0x85b7f5c)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:2810
#6 0x082fdc89 in execute (op_array=0x85b7f5c)
at /dat/dev/php/php-5.0dev/Zend/zend_execute.c:1391
#7 0x082da17f in zend_execute_scripts (type=8, retval=0x0,
file_count=3)
at /dat/dev/php/php-5.0dev/Zend/zend.c:1061
#8 0x08293dc7 in php_execute_script (primary_file=0xbffff930)
at /dat/dev/php/php-5.0dev/main/main.c:1629
#9 0x0830a856 in main (argc=1, argv=0xbffffa04)
at /dat/dev/php/php-5.0dev/sapi/cli/php_cli.c:943
Assinging to Andi.
------------------------------------------------------------------------
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