tor/changes/bug2332

  o Minor bugfixes
    - Fix a bug with handling misformed replies to reverse DNS lookup
      requests in DNSPort.  Bugfix on Tor 0.2.0.1-alpha.  Related to a bug
      reported by doorss.
Always nul-terminate the result passed to evdns_server_add_ptr_reply In dnsserv_resolved(), we carefully made a nul-terminated copy of the answer in a PTR RESOLVED cell... then never used that nul-terminated copy. Ouch. Surprisingly this one isn't as huge a security problem as it could be. The only place where the input to dnsserv_resolved wasn't necessarily nul-terminated was when it was called indirectly from relay.c with the contents of a relay cell's payload. If the end of the payload was filled with junk, eventdns.c would take the strdup() of the name [This part is bad; we might crash there if the cell is in a bad part of the stack or the heap] and get a name of at least length 495[]. eventdns.c then rejects any name of length over 255, so the bogus data would be neither transmitted nor altered. [] If the name was less than 495 bytes long, the client wouldn't actually be reading off the end of the cell. Nonetheless this is a reasonably annoying bug. Better fix it. Found while looking at bug 2332, reported by doorss. Bugfix on 0.2.0.1-alpha. 2011-01-10 22:18:32 +01:00			`o Minor bugfixes`
			`- Fix a bug with handling misformed replies to reverse DNS lookup`
			`requests in DNSPort. Bugfix on Tor 0.2.0.1-alpha. Related to a bug`
			`reported by doorss.`