[tor-bugs] #5650 [Tor]: Tor hogging CPU

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#5650: Tor hogging CPU
--------------------------+------------------------------------
     Reporter:  One Sock  |      Owner:  nickm
         Type:  defect    |     Status:  closed
     Priority:  major     |  Milestone:  Tor: 0.2.3.x-final
    Component:  Tor       |    Version:
   Resolution:  fixed     |   Keywords:  tor-relay 023-backport
Actual Points:            |  Parent ID:
       Points:            |
--------------------------+------------------------------------

Comment (by cypherpunks):

 Merged fix do hides real reason of this bug. Suggests another way to fix
 it.
 {{{
 --- connection.origin.c
 +++ connection.c
 @@ -3068,16 +3068,8 @@
          connection_start_writing(conn);
          return 0;
        case TOR_TLS_WANTREAD:
 -        if (conn->in_connection_handle_write) {
 -          /* We've been invoked from connection_handle_write, because
 we're
 -           * waiting for a TLS renegotiation, the renegotiation started,
 and
 -           * SSL_read returned WANTWRITE.  But now SSL_read is saying
 WANTREAD
 -           * again.  Stop waiting for write events now, or else we'll
 -           * busy-loop until data arrives for us to read. */
 -          connection_stop_writing(conn);
 -          if (!connection_is_reading(conn))
 -            connection_start_reading(conn);
 -        }
 +        if (!connection_is_reading(conn)) /* XXX: It's bug if no reading
 */
 +          connection_start_reading(conn);
          /* we're already reading, one hopes */
          result = 0;
          break;
 @@ -3500,6 +3492,7 @@
        }
        return 0;
      } else if (conn->state == OR_CONN_STATE_TLS_SERVER_RENEGOTIATING) {
 +      connection_stop_writing(conn);
        return connection_handle_read(conn);
      }

 }}}
 in_connection_handle_write flag is no need anymore.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/5650#comment:37>
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