php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #77564 Memory leak in exif_process_IFD_TAG
Submitted: 2019-02-04 07:57 UTC Modified: 2019-02-11 22:17 UTC
From: chamal dot desilva at gmail dot com Assigned: ramsey (profile)
Status: Closed Package: EXIF related
PHP Version: 7.3.1 OS: Windows, Linux
Private report: No CVE-ID: None
Welcome back! If you're the original bug submitter, here's where you can edit the bug or add additional notes.
If you forgot your password, you can retrieve your password here.
Password:
Status:
Package:
Bug Type:
Summary:
From: chamal dot desilva at gmail dot com
New email:
PHP Version: OS:

 

 [2019-02-04 07:57 UTC] chamal dot desilva at gmail dot com
Description:
------------
Version
--------
PHP 7.4.0-dev (cli)
PHP 7.3.1

Description
-----------

This bug is caused by below lines of ext/exif/exif.c file's exif_process_IFD_TAG method.

...
case TAG_USERCOMMENT:
  ImageInfo->UserCommentLength = exif_process_user_comment(ImageInfo, &(ImageInfo->UserComment), &(ImageInfo->UserCommentEncoding), value_ptr, byte_count);
  break;
...

If the image has multiple exif comment tags, exif_process_IFD_TAG or exif_process_user_comment methods do not free already allocated memory
for ImageInfo->UserComment and ImageInfo->UserCommentEncoding, before setting new values.

Configure Line
---------------
./configure --prefix=/php/install --enable-cli --enable-exif --enable-debug --without-pear

Test script:
---------------
<?php
$img = fopen("php://memory","r+");
fwrite($img,hex2bin("ffd8e100464578696600004d4d002a0000000c000000000002928600010000000c00000026928600010000000c00000032554e49434f44450041414141554e49434f44450041414141"));
$s = exif_thumbnail($img);
?>


Actual result:
--------------
Valgrind Output
---------------
Source line numbers are from PHP 7.3.1

export USE_ZEND_ALLOC=0
export ZEND_DONT_UNLOAD_MODULES=1
valgrind --leak-check=yes bin/php test.php

=3566== 5 bytes in 1 blocks are definitely lost in loss record 1 of 2
==3566==    at 0x483021B: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==3566==    by 0x4A0495: __zend_malloc (zend_alloc.c:2904)
==3566==    by 0x49F82D: _emalloc (zend_alloc.c:2494)
==3566==    by 0x49FAE1: _safe_emalloc (zend_alloc.c:2556)
==3566==    by 0x24CC5A: exif_process_string_raw (exif.c:2958)
==3566==    by 0x24CE82: exif_process_user_comment (exif.c:3028)
==3566==    by 0x24DE92: exif_process_IFD_TAG (exif.c:3381)
==3566==    by 0x24E664: exif_process_IFD_in_JPEG (exif.c:3555)
==3566==    by 0x24E942: exif_process_TIFF_in_JPEG (exif.c:3644)
==3566==    by 0x24EA03: exif_process_APP1 (exif.c:3669)
==3566==    by 0x24EECE: exif_scan_JPEG_header (exif.c:3814)
==3566==    by 0x24FDF5: exif_scan_FILE_header (exif.c:4203)
==3566== 
==3566== 8 bytes in 1 blocks are definitely lost in loss record 2 of 2
==3566==    at 0x483021B: malloc (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==3566==    by 0x4A0495: __zend_malloc (zend_alloc.c:2904)
==3566==    by 0x49F82D: _emalloc (zend_alloc.c:2494)
==3566==    by 0x49FC96: _estrdup (zend_alloc.c:2593)
==3566==    by 0x24CD8E: exif_process_user_comment (exif.c:2999)
==3566==    by 0x24DE92: exif_process_IFD_TAG (exif.c:3381)
==3566==    by 0x24E664: exif_process_IFD_in_JPEG (exif.c:3555)
==3566==    by 0x24E942: exif_process_TIFF_in_JPEG (exif.c:3644)
==3566==    by 0x24EA03: exif_process_APP1 (exif.c:3669)
==3566==    by 0x24EECE: exif_scan_JPEG_header (exif.c:3814)
==3566==    by 0x24FDF5: exif_scan_FILE_header (exif.c:4203)
==3566==    by 0x250664: exif_read_from_impl (exif.c:4344)

Patches

Pull Requests

Pull requests:

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2019-02-10 01:59 UTC] stas@php.net
-Type: Security +Type: Bug
 [2019-02-10 18:56 UTC] ramsey@php.net
The following pull request has been associated:

Patch Name: Fix #77564: Memory leak in exif_process_IFD_TAG
On GitHub:  https://github.com/php/php-src/pull/3817
Patch:      https://github.com/php/php-src/pull/3817.patch
 [2019-02-11 22:17 UTC] ramsey@php.net
-Status: Open +Status: Verified -Assigned To: +Assigned To: ramsey
 [2019-02-12 08:29 UTC] nikic@php.net
Automatic comment on behalf of ben@benramsey.com
Revision: http://git.php.net/?p=php-src.git;a=commit;h=c4294440ffc4a59a1298292b76072e6759034a68
Log: Fixed bug #77564: Memory leak in exif_process_IFD_TAG
 [2019-02-12 08:29 UTC] nikic@php.net
-Status: Verified +Status: Closed
 
PHP Copyright © 2001-2024 The PHP Group
All rights reserved.
Last updated: Sun Dec 22 01:01:30 2024 UTC