#18966 [Opn->Csd]: gethostbyaddr() crashes Apache on certain IPs

ID: 18966 Updated by: iliaa@php.net Reported By: php@silisoftware.com -Status: Open +Status: Closed Bug Type: Reproducible crash Operating System: Windows XP Home (NT5.1b2600) PHP Version: 4.2.2 New Comment: This bug has been fixed in CVS. In case this was a PHP problem, snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. In case this was a documentation problem, the fix will show up soon at http://www.php.net/manual/. In case this was a PHP.net website problem, the change will show up on the PHP.net site and on the mirror sites in short time. Thank you for the report, and for helping us make PHP better. Previous Comments: ------------------------------------------------------------------------ [2002-08-29 11:04:18] php@silisoftware.com Webalizer's latest version appears to deal with this issue- it no longer crashes on malformed responses. Microsoft insists that it's a problem with the 3rd-party programs and not XP itself. So given that Analog and Webalizer both used to suffer from this problem, yet both managed to code around it and be XP-compatible, I still think that it should be possible to put some checks in PHP to prevent it crashing the webserver. ------------------------------------------------------------------------ [2002-08-19 12:49:40] php@silisoftware.com Analog seems to have suffered a similar problem until v5.2: http://www.analog.cx/bugs.html "Analog occasionally crashes under Windows XP when doing DNS lookups, if the host returns a malformed response." If this is a similar case to what I'm experiencing, there's no way I can filter out IPs that'll crash my system, but shouldn't PHP be able to check for a properly formed response during the gethostbyaddr() function? ------------------------------------------------------------------------ [2002-08-19 12:01:44] msopacua@idg.nl This does have a very suspicious nameserver: For authoritative answers, see: mitsui.com 3600 IN SOA nyc0x001.mitsui.com amonty.nyc.mitsui.com( 130 ;serial (version) 3600 ;refresh period 600 ;retry refresh this often 86400 ;expiration period 3600 ;minimum TTL ) nyc0x001 But indeed - if Webalizer freaks out, the bug is probably in XP. You may have stumbled upon something really nice here. ------------------------------------------------------------------------ [2002-08-19 11:21:00] edink@php.net This is most likely a bug in your system. I run your script on a Windows 2000 machine and it worked just fine. It simply printed '208.133.226.85'. ------------------------------------------------------------------------ [2002-08-19 11:07:07] php@silisoftware.com gethostbyaddr() crashes Apache (v1.3.24) when looking up certain IPs. Example script: echo gethostbyaddr('208.133.226.85'); Every other IP I've tried (so far about 40,000) didn't have any problems. I tried the above line on another server running PHP4.2.2, Apache v1.3.26 and some form of Linux (2.4.9-31) and that had no problems. Probably related: the Windows port of Webalizer crashes when performing DNS lookups on the same line of the log file, so I suspect it's something to do with DNS lookups in Windows (?). ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=18966&edit=1