UAF ext/zip/php_zip.c

[YuanchengJiang]

Description

The following code:

<?php
$zip = zip_open(__DIR__."/test_procedural.zip");
while ($zip = zip_read($zip)) {
echo zip_entry_name($zip)."\n";
}

Resulted in this output:

=================================================================
==2988798==ERROR: AddressSanitizer: heap-use-after-free on address 0x6020000198b0 at pc 0x000000617aa6 bp 0x7ffcae96fc10 sp 0x7ffcae96f3d0
READ of size 2 at 0x6020000198b0 thread T0
    #0 0x617aa5 in strlen (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x617aa5)
    #1 0x3469ed2 in php_zip_entry_get_info /home/phpfuzz/WorkSpace/flowfusion/php-src/ext/zip/php_zip.c:1386:4
    #2 0x346941e in zif_zip_entry_name /home/phpfuzz/WorkSpace/flowfusion/php-src/ext/zip/php_zip.c:1425:2
    #3 0x448fb1f in ZEND_DO_FCALL_BY_NAME_SPEC_RETVAL_USED_HANDLER /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_vm_execute.h:1698:3
    #4 0x3f7c167 in execute_ex /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_vm_execute.h:58595:7
    #5 0x3f7e3ec in zend_execute /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend_vm_execute.h:64247:2
    #6 0x4d15019 in zend_execute_script /home/phpfuzz/WorkSpace/flowfusion/php-src/Zend/zend.c:1934:3
    #7 0x35298da in php_execute_script_ex /home/phpfuzz/WorkSpace/flowfusion/php-src/main/main.c:2577:13
    #8 0x352aa18 in php_execute_script /home/phpfuzz/WorkSpace/flowfusion/php-src/main/main.c:2617:9
    #9 0x4d2932a in do_cli /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:938:5
    #10 0x4d2380f in main /home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php_cli.c:1313:18
    #11 0x7f300a19fd8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
    #12 0x7f300a19fe3f in __libc_start_main csu/../csu/libc-start.c:392:3
    #13 0x605934 in _start (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x605934)

0x6020000198b0 is located 0 bytes inside of 4-byte region [0x6020000198b0,0x6020000198b4)
freed by thread T0 here:
    #0 0x680592 in free (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x680592)
    #1 0x7f300a3c492e  (/lib/x86_64-linux-gnu/libzip.so.4+0x592e)

previously allocated by thread T0 here:
    #0 0x6807fd in malloc (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x6807fd)
    #1 0x7f300a3d11b7  (/lib/x86_64-linux-gnu/libzip.so.4+0x121b7)

SUMMARY: AddressSanitizer: heap-use-after-free (/home/phpfuzz/WorkSpace/flowfusion/php-src/sapi/cli/php+0x617aa5) in strlen
Shadow bytes around the buggy address:
  0x0c047fffb2c0: fa fa fd fa fa fa 00 00 fa fa 00 00 fa fa 00 fa
  0x0c047fffb2d0: fa fa 00 00 fa fa 00 fa fa fa 00 00 fa fa 00 fa
  0x0c047fffb2e0: fa fa 00 00 fa fa 00 fa fa fa fd fd fa fa fd fa
  0x0c047fffb2f0: fa fa fd fd fa fa 00 fa fa fa fd fd fa fa fd fa
  0x0c047fffb300: fa fa fd fd fa fa 00 fa fa fa 00 06 fa fa fd fd
=>0x0c047fffb310: fa fa fd fa fa fa[fd]fa fa fa fd fd fa fa fd fa
  0x0c047fffb320: fa fa fd fd fa fa fd fa fa fa fd fa fa fa fd fd
  0x0c047fffb330: fa fa fd fa fa fa fd fd fa fa fd fa fa fa fd fa
  0x0c047fffb340: fa fa fd fd fa fa fd fa fa fa 00 07 fa fa fd fd
  0x0c047fffb350: fa fa fd fd fa fa fd fd fa fa fd fa fa fa fa fa
  0x0c047fffb360: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
  Shadow gap:              cc
==2988798==ABORTING

Dependency: test_procedural.zip

PHP Version

nightly

Operating System

ubuntu 22.04

[devnexen]

doing Z_ADDREF_P on the parameter seems to solve the crash.