sctp: Fix SCTP_MAXSEG socket option to comply to spec.
We had a bug that we never stored the user-defined value for
MAXSEG when setting the value on an association. Thus future
PMTU events ended up re-writing the frag point and increasing
it past user limit. Additionally, when setting the option on
the socket/endpoint, we effect all current associations, which
is against spec.
Now, we store the user 'maxseg' value along with the computed
'frag_point'. We inherit 'maxseg' from the socket at association
creation and use it as an upper limit for 'frag_point' when its
set.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 39c3821..1f05b94 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -112,6 +112,7 @@
asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
* 1000;
asoc->frag_point = 0;
+ asoc->user_frag = sp->user_frag;
/* Set the association max_retrans and RTO values from the
* socket values.
@@ -674,7 +675,7 @@
"%d\n", asoc, asoc->pathmtu);
peer->pmtu_pending = 0;
- asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu);
+ asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
/* The asoc->peer.port might not be meaningful yet, but
* initialize the packet structure anyway.
@@ -1330,9 +1331,8 @@
}
if (pmtu) {
- struct sctp_sock *sp = sctp_sk(asoc->base.sk);
asoc->pathmtu = pmtu;
- asoc->frag_point = sctp_frag_point(sp, pmtu);
+ asoc->frag_point = sctp_frag_point(asoc, pmtu);
}
SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 95a5623..89af37a 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2243,7 +2243,7 @@
sctp_assoc_sync_pmtu(asoc);
} else if (asoc) {
asoc->pathmtu = params->spp_pathmtu;
- sctp_frag_point(sp, params->spp_pathmtu);
+ sctp_frag_point(asoc, params->spp_pathmtu);
} else {
sp->pathmtu = params->spp_pathmtu;
}
@@ -2880,15 +2880,10 @@
val -= sizeof(struct sctphdr) +
sizeof(struct sctp_data_chunk);
}
-
- asoc->frag_point = val;
+ asoc->user_frag = val;
+ asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
} else {
sp->user_frag = val;
-
- /* Update the frag_point of the existing associations. */
- list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
- asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu);
- }
}
return 0;