[Pidgin] #4621: MySpace IM causing program freeze at login attempt

[Pidgin]

#4621: MySpace IM causing program freeze at login attempt
-----------------------+----------------------------------------------------
  Reporter:  akb       |       Owner:  jeff         
      Type:  defect    |      Status:  assigned     
  Priority:  critical  |   Milestone:               
 Component:  MySpace   |     Version:  2.3.1        
Resolution:            |    Keywords:  Adium MySpace
   Pending:  0         |  
-----------------------+----------------------------------------------------
Comment (by jeff):

 msim_parse() is being called endlessly, trying to parse the same buddy
 presence update message, because the 15K receive buffer is full. I ran
 Adium with the debug log enabled and it generated a 165,305-line 213 MB
 log file before I killed it. Msimprpl does actually detect that the read
 buffer is full:
 {{{
 17:56:07: (Libpurple: msim) buffer at 0 (max 15360), reading up to 15360
 17:56:07: (Libpurple: msim_input_cb) received 15360 bytes, pushing rxoff
 to 15360, over buffer size of 15360
 17:56:07: Connection Disconnected: gc=b02e190 (Read buffer full)
 17:56:07: <PurpleMySpaceAccount:6e543f0 3>:msimprpl at xyzzy.cjb.net
 accountConnectionReportDisconnect: Read buffer full
 17:56:07: (Libpurple: msim) msim_input_cb: going to null terminate at
 n=15360
 17:56:07: (Libpurple: msim) msim_input_cb: read=15360
 }}}

 It reports this error condition using `purple_connection_error_reason`, in
 myspace.c:msim_input_cb:

 {{{
         /* Only can handle so much data at once...
          * Should be large enough to hold the largest protocol message.
          */
         if (session->rxoff >= MSIM_READ_BUF_SIZE) {
                 purple_debug_error("msim",
                                 "msim_input_cb: %d-byte read buffer full!
 rxoff=%d. "
                                 "If this happens, try recompiling with a
 higher "
                                 "MSIM_READ_BUF_SIZE.",
                                 MSIM_READ_BUF_SIZE, session->rxoff);
                 purple_connection_error_reason (gc,
                                 PURPLE_CONNECTION_ERROR_NETWORK_ERROR,
                                 _("Read buffer full"));
                 return;
         }

 }}}

 and
 {{{
         if (n + session->rxoff >= MSIM_READ_BUF_SIZE) {
                 purple_debug_info("msim_input_cb", "received %d bytes,
 pushing rxoff to %d, over buffer size of %d\n",
                                 n, n + session->rxoff,
 MSIM_READ_BUF_SIZE);
                 /* TODO: g_realloc like msn, yahoo, irc, jabber? */
                 purple_connection_error_reason (gc,
                         PURPLE_CONNECTION_ERROR_NETWORK_ERROR,
                         _("Read buffer full"));
         }
 }}}
 There is a `return` missing here; the function shouldn't continue. I added
 it.

-- 
Ticket URL: <http://developer.pidgin.im/ticket/4621#comment:9>
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