diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
index 20ff237c5eb2f..86f034b524d46 100644
--- a/include/net/sctp/constants.h
+++ b/include/net/sctp/constants.h
@@ -254,11 +254,10 @@ enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 };
#define SCTP_TSN_MAP_SIZE 4096
/* We will not record more than this many duplicate TSNs between two
- * SACKs. The minimum PMTU is 576. Remove all the headers and there
- * is enough room for 131 duplicate reports. Round down to the
+ * SACKs. The minimum PMTU is 512. Remove all the headers and there
+ * is enough room for 117 duplicate reports. Round down to the
* nearest power of 2.
*/
-enum { SCTP_MIN_PMTU = 576 };
enum { SCTP_MAX_DUP_TSNS = 16 };
enum { SCTP_MAX_GABS = 16 };
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 28b996d634907..f66d443500079 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -428,32 +428,6 @@ static inline int sctp_list_single_entry(struct list_head *head)
return (head->next != head) && (head->next == head->prev);
}
-/* Break down data chunks at this point. */
-static inline int sctp_frag_point(const struct sctp_association *asoc, int pmtu)
-{
- struct sctp_sock *sp = sctp_sk(asoc->base.sk);
- struct sctp_af *af = sp->pf->af;
- int frag = pmtu;
-
- frag -= af->ip_options_len(asoc->base.sk);
- frag -= af->net_header_len;
- frag -= sizeof(struct sctphdr) + sctp_datachk_len(&asoc->stream);
-
- if (asoc->user_frag)
- frag = min_t(int, frag, asoc->user_frag);
-
- frag = SCTP_TRUNC4(min_t(int, frag, SCTP_MAX_CHUNK_LEN -
- sctp_datachk_len(&asoc->stream)));
-
- return frag;
-}
-
-static inline void sctp_assoc_pending_pmtu(struct sctp_association *asoc)
-{
- sctp_assoc_sync_pmtu(asoc);
- asoc->pmtu_pending = 0;
-}
-
static inline bool sctp_chunk_pending(const struct sctp_chunk *chunk)
{
return !list_empty(&chunk->list);
@@ -607,17 +581,29 @@ static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *
return t->dst;
}
-static inline bool sctp_transport_pmtu_check(struct sctp_transport *t)
+/* Calculate max payload size given a MTU, or the total overhead if
+ * given MTU is zero
+ */
+static inline __u32 sctp_mtu_payload(const struct sctp_sock *sp,
+ __u32 mtu, __u32 extra)
{
- __u32 pmtu = max_t(size_t, SCTP_TRUNC4(dst_mtu(t->dst)),
- SCTP_DEFAULT_MINSEGMENT);
+ __u32 overhead = sizeof(struct sctphdr) + extra;
- if (t->pathmtu == pmtu)
- return true;
+ if (sp)
+ overhead += sp->pf->af->net_header_len;
+ else
+ overhead += sizeof(struct ipv6hdr);
- t->pathmtu = pmtu;
+ if (WARN_ON_ONCE(mtu && mtu <= overhead))
+ mtu = overhead;
- return false;
+ return mtu ? mtu - overhead : overhead;
+}
+
+static inline __u32 sctp_dst_mtu(const struct dst_entry *dst)
+{
+ return SCTP_TRUNC4(max_t(__u32, dst_mtu(dst),
+ SCTP_DEFAULT_MINSEGMENT));
}
#endif /* __net_sctp_h__ */
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 05594b248e527..ebf809eed33ad 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -2097,6 +2097,8 @@ int sctp_assoc_update(struct sctp_association *old,
__u32 sctp_association_get_next_tsn(struct sctp_association *);
+void sctp_assoc_update_frag_point(struct sctp_association *asoc);
+void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu);
void sctp_assoc_sync_pmtu(struct sctp_association *asoc);
void sctp_assoc_rwnd_increase(struct sctp_association *, unsigned int);
void sctp_assoc_rwnd_decrease(struct sctp_association *, unsigned int);
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index a8f3b088fcb2a..039fdb862b179 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -652,33 +652,20 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
*/
peer->param_flags = asoc->param_flags;
- sctp_transport_route(peer, NULL, sp);
-
/* Initialize the pmtu of the transport. */
- if (peer->param_flags & SPP_PMTUD_DISABLE) {
- if (asoc->pathmtu)
- peer->pathmtu = asoc->pathmtu;
- else
- peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
- }
+ sctp_transport_route(peer, NULL, sp);
/* If this is the first transport addr on this association,
* initialize the association PMTU to the peer's PMTU.
* If not and the current association PMTU is higher than the new
* peer's PMTU, reset the association PMTU to the new peer's PMTU.
*/
- if (asoc->pathmtu)
- asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
- else
- asoc->pathmtu = peer->pathmtu;
-
- pr_debug("%s: association:%p PMTU set to %d\n", __func__, asoc,
- asoc->pathmtu);
+ sctp_assoc_set_pmtu(asoc, asoc->pathmtu ?
+ min_t(int, peer->pathmtu, asoc->pathmtu) :
+ peer->pathmtu);
peer->pmtu_pending = 0;
- asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
-
/* The asoc->peer.port might not be meaningful yet, but
* initialize the packet structure anyway.
*/
@@ -1381,6 +1368,31 @@ sctp_assoc_choose_alter_transport(struct sctp_association *asoc,
}
}
+void sctp_assoc_update_frag_point(struct sctp_association *asoc)
+{
+ int frag = sctp_mtu_payload(sctp_sk(asoc->base.sk), asoc->pathmtu,
+ sctp_datachk_len(&asoc->stream));
+
+ if (asoc->user_frag)
+ frag = min_t(int, frag, asoc->user_frag);
+
+ frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN -
+ sctp_datachk_len(&asoc->stream));
+
+ asoc->frag_point = SCTP_TRUNC4(frag);
+}
+
+void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu)
+{
+ if (asoc->pathmtu != pmtu) {
+ asoc->pathmtu = pmtu;
+ sctp_assoc_update_frag_point(asoc);
+ }
+
+ pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc,
+ asoc->pathmtu, asoc->frag_point);
+}
+
/* Update the association's pmtu and frag_point by going through all the
* transports. This routine is called when a transport's PMTU has changed.
*/
@@ -1393,24 +1405,16 @@ void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
return;
/* Get the lowest pmtu of all the transports. */
- list_for_each_entry(t, &asoc->peer.transport_addr_list,
- transports) {
+ list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
if (t->pmtu_pending && t->dst) {
- sctp_transport_update_pmtu(
- t, SCTP_TRUNC4(dst_mtu(t->dst)));
+ sctp_transport_update_pmtu(t, sctp_dst_mtu(t->dst));
t->pmtu_pending = 0;
}
if (!pmtu || (t->pathmtu < pmtu))
pmtu = t->pathmtu;
}
- if (pmtu) {
- asoc->pathmtu = pmtu;
- asoc->frag_point = sctp_frag_point(asoc, pmtu);
- }
-
- pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc,
- asoc->pathmtu, asoc->frag_point);
+ sctp_assoc_set_pmtu(asoc, pmtu);
}
/* Should we send a SACK to update our peer? */
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index be296d633e951..79daa98208c39 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -172,8 +172,6 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
struct list_head *pos, *temp;
struct sctp_chunk *chunk;
struct sctp_datamsg *msg;
- struct sctp_sock *sp;
- struct sctp_af *af;
int err;
msg = sctp_datamsg_new(GFP_KERNEL);
@@ -192,12 +190,7 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
/* This is the biggest possible DATA chunk that can fit into
* the packet
*/
- sp = sctp_sk(asoc->base.sk);
- af = sp->pf->af;
- max_data = asoc->pathmtu - af->net_header_len -
- sizeof(struct sctphdr) - sctp_datachk_len(&asoc->stream) -
- af->ip_options_len(asoc->base.sk);
- max_data = SCTP_TRUNC4(max_data);
+ max_data = asoc->frag_point;
/* If the the peer requested that we authenticate DATA chunks
* we need to account for bundling of the AUTH chunks along with
@@ -222,9 +215,6 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
}
}
- /* Check what's our max considering the above */
- max_data = min_t(size_t, max_data, asoc->frag_point);
-
/* Set first_len and then account for possible bundles on first frag */
first_len = max_data;
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 690d8557bb7bf..e672dee302c70 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -90,8 +90,8 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
{
struct sctp_transport *tp = packet->transport;
struct sctp_association *asoc = tp->asoc;
+ struct sctp_sock *sp = NULL;
struct sock *sk;
- size_t overhead = sizeof(struct ipv6hdr) + sizeof(struct sctphdr);
pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag);
packet->vtag = vtag;
@@ -102,28 +102,20 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
/* set packet max_size with pathmtu, then calculate overhead */
packet->max_size = tp->pathmtu;
+
if (asoc) {
- struct sctp_sock *sp = sctp_sk(asoc->base.sk);
- struct sctp_af *af = sp->pf->af;
-
- overhead = af->net_header_len +
- af->ip_options_len(asoc->base.sk);
- overhead += sizeof(struct sctphdr);
- packet->overhead = overhead;
- packet->size = overhead;
- } else {
- packet->overhead = overhead;
- packet->size = overhead;
- return;
+ sk = asoc->base.sk;
+ sp = sctp_sk(sk);
}
+ packet->overhead = sctp_mtu_payload(sp, 0, 0);
+ packet->size = packet->overhead;
+
+ if (!asoc)
+ return;
/* update dst or transport pathmtu if in need */
- sk = asoc->base.sk;
if (!sctp_transport_dst_check(tp)) {
- sctp_transport_route(tp, NULL, sctp_sk(sk));
- if (asoc->param_flags & SPP_PMTUD_ENABLE)
- sctp_assoc_sync_pmtu(asoc);
- } else if (!sctp_transport_pmtu_check(tp)) {
+ sctp_transport_route(tp, NULL, sp);
if (asoc->param_flags & SPP_PMTUD_ENABLE)
sctp_assoc_sync_pmtu(asoc);
}
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 80835ac26d2c3..1b4593b842b00 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -644,16 +644,15 @@ static int sctp_send_asconf_add_ip(struct sock *sk,
list_for_each_entry(trans,
&asoc->peer.transport_addr_list, transports) {
- /* Clear the source and route cache */
- sctp_transport_dst_release(trans);
trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
2*asoc->pathmtu, 4380));
trans->ssthresh = asoc->peer.i.a_rwnd;
trans->rto = asoc->rto_initial;
sctp_max_rto(asoc, trans);
trans->rtt = trans->srtt = trans->rttvar = 0;
+ /* Clear the source and route cache */
sctp_transport_route(trans, NULL,
- sctp_sk(asoc->base.sk));
+ sctp_sk(asoc->base.sk));
}
}
retval = sctp_send_asconf(asoc, chunk);
@@ -896,7 +895,6 @@ static int sctp_send_asconf_del_ip(struct sock *sk,
*/
list_for_each_entry(transport, &asoc->peer.transport_addr_list,
transports) {
- sctp_transport_dst_release(transport);
sctp_transport_route(transport, NULL,
sctp_sk(asoc->base.sk));
}
@@ -1895,6 +1893,7 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
struct sctp_sndrcvinfo *sinfo)
{
struct sock *sk = asoc->base.sk;
+ struct sctp_sock *sp = sctp_sk(sk);
struct net *net = sock_net(sk);
struct sctp_datamsg *datamsg;
bool wait_connect = false;
@@ -1913,13 +1912,16 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
goto err;
}
- if (sctp_sk(sk)->disable_fragments && msg_len > asoc->frag_point) {
+ if (sp->disable_fragments && msg_len > asoc->frag_point) {
err = -EMSGSIZE;
goto err;
}
- if (asoc->pmtu_pending)
- sctp_assoc_pending_pmtu(asoc);
+ if (asoc->pmtu_pending) {
+ if (sp->param_flags & SPP_PMTUD_ENABLE)
+ sctp_assoc_sync_pmtu(asoc);
+ asoc->pmtu_pending = 0;
+ }
if (sctp_wspace(asoc) < msg_len)
sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));
@@ -1936,7 +1938,7 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
if (err)
goto err;
- if (sctp_sk(sk)->strm_interleave) {
+ if (sp->strm_interleave) {
timeo = sock_sndtimeo(sk, 0);
err = sctp_wait_for_connect(asoc, &timeo);
if (err)
@@ -2539,7 +2541,7 @@ static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
trans->pathmtu = params->spp_pathmtu;
sctp_assoc_sync_pmtu(asoc);
} else if (asoc) {
- asoc->pathmtu = params->spp_pathmtu;
+ sctp_assoc_set_pmtu(asoc, params->spp_pathmtu);
} else {
sp->pathmtu = params->spp_pathmtu;
}
@@ -3209,7 +3211,6 @@ static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsign
static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
{
struct sctp_sock *sp = sctp_sk(sk);
- struct sctp_af *af = sp->pf->af;
struct sctp_assoc_value params;
struct sctp_association *asoc;
int val;
@@ -3231,30 +3232,24 @@ static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned
return -EINVAL;
}
+ asoc = sctp_id2assoc(sk, params.assoc_id);
+
if (val) {
int min_len, max_len;
+ __u16 datasize = asoc ? sctp_datachk_len(&asoc->stream) :
+ sizeof(struct sctp_data_chunk);
- min_len = SCTP_DEFAULT_MINSEGMENT - af->net_header_len;
- min_len -= af->ip_options_len(sk);
- min_len -= sizeof(struct sctphdr) +
- sizeof(struct sctp_data_chunk);
-
- max_len = SCTP_MAX_CHUNK_LEN - sizeof(struct sctp_data_chunk);
+ min_len = sctp_mtu_payload(sp, SCTP_DEFAULT_MINSEGMENT,
+ datasize);
+ max_len = SCTP_MAX_CHUNK_LEN - datasize;
if (val < min_len || val > max_len)
return -EINVAL;
}
- asoc = sctp_id2assoc(sk, params.assoc_id);
if (asoc) {
- if (val == 0) {
- val = asoc->pathmtu - af->net_header_len;
- val -= af->ip_options_len(sk);
- val -= sizeof(struct sctphdr) +
- sctp_datachk_len(&asoc->stream);
- }
asoc->user_frag = val;
- asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
+ sctp_assoc_update_frag_point(asoc);
} else {
if (params.assoc_id && sctp_style(sk, UDP))
return -EINVAL;
diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 47f82bd794d91..4a95e260b674b 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -242,9 +242,18 @@ void sctp_transport_pmtu(struct sctp_transport *transport, struct sock *sk)
&transport->fl, sk);
}
- if (transport->dst) {
- transport->pathmtu = SCTP_TRUNC4(dst_mtu(transport->dst));
- } else
+ if (transport->param_flags & SPP_PMTUD_DISABLE) {
+ struct sctp_association *asoc = transport->asoc;
+
+ if (!transport->pathmtu && asoc && asoc->pathmtu)
+ transport->pathmtu = asoc->pathmtu;
+ if (transport->pathmtu)
+ return;
+ }
+
+ if (transport->dst)
+ transport->pathmtu = sctp_dst_mtu(transport->dst);
+ else
transport->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
}
@@ -290,6 +299,7 @@ void sctp_transport_route(struct sctp_transport *transport,
struct sctp_association *asoc = transport->asoc;
struct sctp_af *af = transport->af_specific;
+ sctp_transport_dst_release(transport);
af->get_dst(transport, saddr, &transport->fl, sctp_opt2sk(opt));
if (saddr)
@@ -297,21 +307,14 @@ void sctp_transport_route(struct sctp_transport *transport,
else
af->get_saddr(opt, transport, &transport->fl);
- if ((transport->param_flags & SPP_PMTUD_DISABLE) && transport->pathmtu) {
- return;
- }
- if (transport->dst) {
- transport->pathmtu = SCTP_TRUNC4(dst_mtu(transport->dst));
+ sctp_transport_pmtu(transport, sctp_opt2sk(opt));
- /* Initialize sk->sk_rcv_saddr, if the transport is the
- * association's active path for getsockname().
- */
- if (asoc && (!asoc->peer.primary_path ||
- (transport == asoc->peer.active_path)))
- opt->pf->to_sk_saddr(&transport->saddr,
- asoc->base.sk);
- } else
- transport->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
+ /* Initialize sk->sk_rcv_saddr, if the transport is the
+ * association's active path for getsockname().
+ */
+ if (transport->dst && asoc &&
+ (!asoc->peer.primary_path || transport == asoc->peer.active_path))
+ opt->pf->to_sk_saddr(&transport->saddr, asoc->base.sk);
}
/* Hold a reference to a transport. */