Edit report at https://bugs.php.net/bug.php?id=76844&edit=1
ID: 76844
Updated by: nikic@php.net
Reported by: denis at bitrix dot ru
Summary: PHP crashes on big file with array inside
Status: Open
Type: Bug
Package: opcache
Operating System: Ubuntu 14.04.5 LTS
PHP Version: 7.2.9
Block user comment: N
Private report: N
New Comment:
@rhsoft: The interned strings buffer is not really relevant to this issue. As @cmb pointed out, this
is a stack overflow in zend_ssa_check_scc_var. The test script has a very long (and linear) chain of
uses, each of which results in another recursive call. This could be resolved either by making the
algorithm non-recursive or adding / changing some limits. E.g. we might want to punt on SSA
optimizations if there are too many SSA vars.
Previous Comments:
------------------------------------------------------------------------
[2018-09-06 08:31:07] spam2 at rhsoft dot net
"Fatal Error Zend OPcache cannot allocate buffer for interned strings" clearly indicates
that "opcache.memory_consumption" is way too small
frankly if you can allocate 18 MB i guess someone has lowered the default value
------
-rw-r--r-- 1 root root 198K 2018-03-05 16:37
/usr/share/phpMyAdmin/vendor/tecnickcom/tcpdf/fonts/dejavusans.ph
/usr/share/phpMyAdmin/vendor/tecnickcom/tcpdf/fonts/dejavusans.php allocates 1,36 MB in opcache so
your guess 16M should be enough for 12M file is pretty wrong
------------------------------------------------------------------------
[2018-09-06 08:24:47] denis at bitrix dot ru
opcache.interned_strings_buffer doesn't seem to affect:
$ php -i|grep opcache.interned_strings_buffer
opcache.interned_strings_buffer => 8 => 8
$ php -d opcache.enable_cli=1 -d opcache.interned_strings_buffer=16 restore.file_list.php
Segmentation fault
I guess, 16M should be enough for 12M file. And further I got an error:
$ php -d opcache.enable_cli=1 -d opcache.interned_strings_buffer=18 restore.file_list.php
Thu Sep 6 10:19:14 2018 (12707): Fatal Error Zend OPcache cannot allocate buffer for interned
strings
------------------------------------------------------------------------
[2018-09-05 18:13:41] cmb@php.net
On a quick glance, this looks like a stack overflow.
------------------------------------------------------------------------
[2018-09-05 17:13:08] spam2 at rhsoft dot net
check your opcache settings especially interned strings buffer
------------------------------------------------------------------------
[2018-09-05 17:03:28] denis at bitrix dot ru
Description:
------------
I have auto generated 12M script which causes segmentation fault with opcache enabled.
$ gdb -ex=r --args php restore.file_list.php
GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.3) 7.7.1
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from php...Reading symbols from
/usr/lib/debug/.build-id/c0/4daf2c7bc6200e0a02e127d552d4290d6678e0.debug...done.
done.
Starting program: /usr/bin/php restore.file_list.php
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008, ssa=ssa@entry=0x7ffff59de028,
var=65384, index=index@entry=0x7fffffffa48c, dfs=dfs@entry=0x7fffe9801000,
root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490) at
/build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:173
173 {
(gdb) bt 10
#0 zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008, ssa=ssa@entry=0x7ffff59de028,
var=65384, index=index@entry=0x7fffffffa48c, dfs=dfs@entry=0x7fffe9801000,
root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490) at
/build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:173
#1 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#2 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#3 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#4 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#5 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#6 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#7 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#8 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
#9 0x00007ffff4a7eed6 in zend_ssa_check_scc_var (op_array=op_array@entry=0x7ffff5883008,
ssa=ssa@entry=0x7ffff59de028, var=<optimized out>, index=index@entry=0x7fffffffa48c,
dfs=dfs@entry=0x7fffe9801000, root=root@entry=0x7fffe9a01000, stack=stack@entry=0x7fffffffa490)
at /build/php7.2-pz0P3X/php7.2-7.2.9/ext/opcache/Optimizer/zend_inference.c:182
(More stack frames follow...)
(gdb) bt -1
#65394 0x00005555556422be in main (argc=2, argv=0x555555bfd6e0) at
/build/php7.2-pz0P3X/php7.2-7.2.9/sapi/cli/php_cli.c:1404
(gdb) zbacktrace
(gdb)
Test script:
---------------
The script is uploaded to https://my.pcloud.com/publink/show?code=XZMTED7ZcA3xXabVtHSiwtefBkWj74HBSY1y
It is 12M length but very simple:
$ head restore.file_list.php
<?
$a['modules/main/include/virtual_file_system.php'] = 1;
$a['modules/main/include/epilog_popup_admin.php'] = 1;
$a['modules/main/include/prolog_before.php'] = 1;
$a['modules/main/include/condition.php'] = 1;
$a['modules/main/include/mainpage.php'] = 1;
$a['modules/main/include/epilog.php'] = 1;
$a['modules/main/include/include_statistics_before.php'] = 1;
$a['modules/main/include/include_statistics.php'] = 1;
$a['modules/main/include/dbconn_error.php'] = 1;
$ tail restore.file_list.php
$a['components/bitrix/lists.element.edit/lang/en/ajax.php'] = 1;
$a['components/bitrix/lists.element.edit/lang/en/component.php'] = 1;
$a['components/bitrix/lists.element.edit/lang/en/.description.php'] = 1;
$a['components/bitrix/lists.element.edit/.description.php'] = 1;
$a['components/bitrix/tasks.interface.header/templates/.default/template.php'] = 1;
$a['components/bitrix/tasks.interface.header/templates/.default/script.js'] = 1;
$a['components/bitrix/tasks.interface.header/templates/.default/style.min.css'] = 1;
$a['components/bitrix/tasks.interface.header/templates/.default/script.map.js'] = 1;
$a['components/bitrix/tasks.interface.header/templates/.default/script.min.js'] = 1;
$a['components/bitrix/tasks.interface.header/class.php'] = 1;
Actual result:
--------------
$ php -d opcache.enable_cli=0 restore.file_list.php
$
$ php -d opcache.enable_cli=1 restore.file_list.php
Segmentation fault
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=76844&edit=1