On 19 October 2018 at 04:22, Jason Wang <address@hidden> wrote:
From: Zhang Chen <address@hidden>
We add almost full TCP state machine in filter-rewriter, except
TCPS_LISTEN and some simplify in VM active close FIN states.
The reason for this simplify job is because guest kernel will track
the TCP status and wait 2MSL time too, if client resend the FIN packet,
guest will resend the last ACK, so we needn't wait 2MSL time in filter-rewriter.
After a net connection is closed, we didn't clear its related resources
in connection_track_table, which will lead to memory leak.
Let's track the state of net connection, if it is closed, its related
resources will be cleared up.
Hi. Coverity (CID 1396477) points out that here:
+ /*
+ * Active close step 2.
+ */
+ if (conn->tcp_state == TCPS_FIN_WAIT_1) {
+ conn->tcp_state = TCPS_TIME_WAIT;
...this assignment to conn->tcp_state has no effect, because...
+ /*
+ * For simplify implementation, we needn't wait 2MSL time
+ * in filter rewriter. Because guest kernel will track the
+ * TCP status and wait 2MSL time, if client resend the FIN
+ * packet, guest will apply the last ACK too.
+ */
+ conn->tcp_state = TCPS_CLOSED;
...we immediately overwrite it with a different value.
+ g_hash_table_remove(rf->connection_track_table, key);
+ }
}
What was the intention of the code here?
thanks
-- PMM