Bug #72857 [Opn->Csd]: stream_socket_recvfrom read access violation

Edit report at https://bugs.php.net/bug.php?id=72857&edit=1 ID: 72857 Updated by: ab@php.net Reported by: fernando at null-life dot com Summary: stream_socket_recvfrom read access violation -Status: Open +Status: Closed Type: Bug Package: Sockets related Operating System: Windows PHP Version: 7.0.9 Block user comment: N Private report: N New Comment: Automatic comment on behalf of ab Revision: http://git.php.net/?p=php-src.git;a=commit;h=5391bb8be03c30cc742e67ce9f95b2767a40198d Log: Fixed #72857 stream_socket_recvfrom read access violation Previous Comments: ------------------------------------------------------------------------ [2016-08-16 18:43:18] fernando at null-life dot com Description: ------------ Attached test script crashes PHP interpreter on Windows. Using PHP 7.0.10 RC1 from windows.php.net https://github.com/php/php-src/blob/master/ext/standard/streamsfuncs.c#L398 if (recvd >= 0) { if (zremote) { crash ----> ZVAL_STR(zremote, remote_addr); } ZSTR_VAL(read_buf)[recvd] = '\0'; ZSTR_LEN(read_buf) = recvd; RETURN_NEW_STR(read_buf); } 0:000:x86> r eax=00001406 ebx=1686b1e0 ecx=00000000 edx=1685d578 esi=168549e0 edi=00000000 eip=54e2173f esp=08bfe3dc ebp=168130f0 iopl=0 nv up ei pl nz na pe nc cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206 php7!zif_stream_socket_recvfrom+0x13f: 54e2173f f6410502 test byte ptr [ecx+5],2 ds:002b:00000005=?? 0:000:x86> ?? zremote struct _zval_struct * 0x0000000a +0x000 value : _zend_value +0x008 u1 : <unnamed-tag> +0x00c u2 : <unnamed-tag> 0:000:x86> ?? remote_addr struct _zend_string * 0x00000000 Test script: --------------- <?php $fp0 = fopen('stream_socket_recvfrom.tmp', 'w'); $v2=10; $v3=STREAM_PEEK; $v4="A"; stream_socket_recvfrom($fp0,$v2,$v3,$v4); Expected result: ---------------- No crash Actual result: -------------- (1f68.1430): Access violation - code c0000005 (first chance) First chance exceptions are reported before any exception handling. This exception may be expected and handled. php7!zif_stream_socket_recvfrom+0x13f: 54e2173f f6410502 test byte ptr [ecx+5],2 ds:002b:00000005=?? Processing initial command 'r;!exploitable -v' 0:000:x86> r;!exploitable -v eax=00001406 ebx=1686b1e0 ecx=00000000 edx=1685d578 esi=168549e0 edi=00000000 eip=54e2173f esp=08bfe3dc ebp=168130f0 iopl=0 nv up ei pl nz na pe nc cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206 php7!zif_stream_socket_recvfrom+0x13f: 54e2173f f6410502 test byte ptr [ecx+5],2 ds:002b:00000005=?? !exploitable 1.6.0.0 HostMachine\HostUser Executing Processor Architecture is x86 Debuggee is in User Mode Debuggee is a live user mode debugging session on the local machine Event Type: Exception Exception Faulting Address: 0x5 First Chance Exception Type: STATUS_ACCESS_VIOLATION (0xC0000005) Exception Sub-Type: Read Access Violation Faulting Instruction:54e2173f test byte ptr [ecx+5],2 Basic Block: 54e2173f test byte ptr [ecx+5],2 Tainted Input operands: 'ecx' 54e21743 mov ecx,6 54e21748 cmovne eax,ecx 54e2174b mov dword ptr [edx+8],eax 54e2174e mov eax,dword ptr [esp+28h] 54e21752 mov byte ptr [esi+edi+10h],0 54e21757 mov dword ptr [esi+0ch],edi 54e2175a mov dword ptr [eax],esi 54e2175c pop esi 54e2175d pop edi 54e2175e mov dword ptr [eax+8],1406h 54e21765 pop ebx 54e21766 add esp,14h 54e21769 ret Exception Hash (Major/Minor): 0x358d862f.0xff5fe61a Hash Usage : Stack Trace: Major+Minor : php7!zif_stream_socket_recvfrom+0x13f Major+Minor : php7!ZEND_DO_ICALL_SPEC_HANDLER+0x51 Major+Minor : php7!execute_ex+0x21 Major+Minor : php7!zend_execute+0x325 Major+Minor : php7!zend_execute_scripts+0xab Minor : php7!php_execute_script+0x2aa Minor : php!do_cli+0x7e3 Minor : php!main+0x44e Minor : php!__scrt_common_main_seh+0xf9 Minor : KERNEL32!BaseThreadInitThunk+0x24 Minor : ntdll_774c0000!__RtlUserThreadStart+0x2f Minor : ntdll_774c0000!_RtlUserThreadStart+0x1b Instruction Address: 0x0000000054e2173f Source File: c:\php-sdk\php70\vc14\x86\php-7.0.10rc1\ext\standard\streamsfuncs.c Source Line: 398 Description: Read Access Violation near NULL Short Description: ReadAVNearNull Exploitability Classification: PROBABLY_NOT_EXPLOITABLE Recommended Bug Title: Read Access Violation near NULL starting at php7!zif_stream_socket_recvfrom+0x000000000000013f (Hash=0x358d862f.0xff5fe61a) This is a user mode read access violation near null, and is probably not exploitable. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=72857&edit=1