sctp: Disallow new connection on a closing socket
If a socket has a lot of association that are in the process of
of being closed/aborted, it is possible for a remote to establish
new associations during the time period that the old ones are shutting
down. If this was a result of a close() call, there will be no socket
and will cause a memory leak. We'll prevent this by setting the
socket state to CLOSING and disallow new associations when in this state.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 7288192..50225dd 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -334,6 +334,15 @@
if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t)))
return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
+ /* If the INIT is coming toward a closing socket, we'll send back
+ * and ABORT. Essentially, this catches the race of INIT being
+ * backloged to the socket at the same time as the user isses close().
+ * Since the socket and all its associations are going away, we
+ * can treat this OOTB
+ */
+ if (sctp_sstate(ep->base.sk, CLOSING))
+ return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands);
+
/* Verify the INIT chunk before processing it. */
err_chunk = NULL;
if (!sctp_verify_init(asoc, chunk->chunk_hdr->type,