Bug #51761 [Opn]: Memory Error: IPR in language scanner
Edit report at http://bugs.php.net/bug.php?id=51761&edit=1
ID: 51761
Updated by: felipe@php.net
Reported by: russell dot tempero at rightnow dot com
Summary: Memory Error: IPR in language scanner
Status: Open
Type: Bug
Package: Scripting Engine problem
Operating System: Linux
PHP Version: 5.3.2
New Comment:
We are using re2c instead of flex for 5.3+.
Previous Comments:
------------------------------------------------------------------------
[2010-05-13 19:11:09] russell dot tempero at rightnow dot com
If you are confident that these errors can be fixed by altering the
grammar, I'll do some more looking to see what I can come up with. This
is probably going to take me a little while though.
Based on what I was seeing, I thought this was more a problem with how
flex generated the scanner from the grammar.
------------------------------------------------------------------------
[2010-05-12 09:34:12] mike@php.net
This should have been set to feedback, shouldn't it?
------------------------------------------------------------------------
[2010-05-08 11:58:17] kalle@php.net
Hi
You should change the grammar in zend_language_scanner.l instead of the
.c file which is generated based on the contains from the .l file. Else
the patch looks good
------------------------------------------------------------------------
[2010-05-07 00:21:08] russell dot tempero at rightnow dot com
Here is some useful debug information if you wish to trace exactly where
the IPRs are happening:
.
.
.
state: 476 char: ? addr: 0xf1c7885e
state: 140 char: ? addr: 0xf1c7885e
state: 121 char: ? addr: 0xf1c7885e
state: -1 char: ? addr: 0xffce705b
state: 166 char: ? addr: 0xf1c7885e
state: 201 char: > addr: 0xf1c7885f
state: 203 char:
addr: 0xf1c78860
RUSSELL: YYCURSOR: 0xf1c78860 YYLIMIT: 0xf1c78861
state: 202 char:
state: 0 char:
state: 4 char:
state: 3 char:
RUSSELL: returning 0 in yy3
------------------------------------------------------------------------
[2010-05-07 00:13:10] russell dot tempero at rightnow dot com
Description:
------------
When running PHP through Purify, I am seeing Invalid Pointer Read (IPR)
errors such as the following:
IPR: Invalid pointer read:
* This is occurring while in thread 8075:
lex_scan [zend_language_scanner.c:3174]
zendlex [zend_compile.c:4950]
zendparse [zend_language_parser.c:3280]
compile_file [zend_language_scanner.l:343]
rnt_compile_file [rnt_opcode_cache.c:1008]
compile_filename [zend_language_scanner.l:386]
* Reading 1 byte from 0xf735f332 between the heap and the stack.
It appears that script files are memory mapped and then a cursor pointer
is used to iterate over the mapped memory. The problem is that the
cursor pointer is not properly checked when reaching the end of the file
and memory values are read that are not part of the mapped memory. I
manually fixed one case of this (see attached diff). However, there are
others.
It looks like this file is generated (using flex?) so this is probably
not actually a PHP issue. However, I thought I would start here. Let me
know if this needs to be submitted to somebody else.
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/bug.php?id=51761&edit=1
Thread (8 messages)