[PATCH net-next 06/14] sctp: annotate data-races around sctp sysctls
From: Jiayuan Chen
Date: Sun Nov 08 2026 - 22:01:37 EST
rto_min, rto_max, rto_initial, hb_interval, sack_timeout,
valid_cookie_life, max_burst, max_retrans_path, max_retrans_association,
max_retrans_init, pf_retrans, ps_retrans, pf_expose, pf_enable, udp_port,
encap_port, probe_interval, addip_enable, addip_noauth, auth_enable,
default_auto_asconf, prsctp_enable, reconf_enable, ecn_enable,
intl_enable, cookie_auth_enable, cookie_preserve_enable, sndbuf_policy,
rcvbuf_policy, rwnd_upd_shift, scope_policy and max_autoclose can be
read concurrently with the sysctl handlers that update them, and the
rto_min, rto_max, udp_port, probe_interval, auth_enable and
cookie_hmac_alg handlers store them with plain writes. Add READ_ONCE() to
the readers and WRITE_ONCE() to those handlers.
Signed-off-by: Jiayuan Chen <jiayuan.chen@xxxxxxxxx>
---
net/sctp/associola.c | 2 +-
net/sctp/bind_addr.c | 2 +-
net/sctp/endpointola.c | 14 ++++++------
net/sctp/input.c | 2 +-
net/sctp/sm_make_chunk.c | 6 +++---
net/sctp/sm_sideeffect.c | 2 +-
net/sctp/sm_statefuns.c | 6 +++---
net/sctp/socket.c | 46 +++++++++++++++++++++-------------------
net/sctp/sysctl.c | 16 +++++++-------
net/sctp/transport.c | 6 +++---
10 files changed, 52 insertions(+), 50 deletions(-)
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 4521be3bd85aa..0a814faaea601 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -1454,7 +1454,7 @@ static inline bool sctp_peer_needs_update(struct sctp_association *asoc)
case SCTP_STATE_SHUTDOWN_SENT:
if ((asoc->rwnd > asoc->a_rwnd) &&
((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
- (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift),
+ (asoc->base.sk->sk_rcvbuf >> READ_ONCE(net->sctp.rwnd_upd_shift)),
asoc->pathmtu)))
return true;
break;
diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c
index 31737f144c7f0..36cea9ae2ad18 100644
--- a/net/sctp/bind_addr.c
+++ b/net/sctp/bind_addr.c
@@ -530,7 +530,7 @@ int sctp_in_scope(struct net *net, const union sctp_addr *addr,
* Address scoping can be selectively controlled via sysctl
* option
*/
- switch (net->sctp.scope_policy) {
+ switch (READ_ONCE(net->sctp.scope_policy)) {
case SCTP_SCOPE_POLICY_DISABLE:
return 1;
case SCTP_SCOPE_POLICY_ENABLE:
diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c
index a15b599b20b76..49d9c5c0babc1 100644
--- a/net/sctp/endpointola.c
+++ b/net/sctp/endpointola.c
@@ -54,8 +54,8 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
struct net *net = sock_net(sk);
struct sctp_shared_key *null_key;
- ep->asconf_enable = net->sctp.addip_enable;
- ep->auth_enable = net->sctp.auth_enable;
+ ep->asconf_enable = READ_ONCE(net->sctp.addip_enable);
+ ep->auth_enable = READ_ONCE(net->sctp.auth_enable);
if (ep->auth_enable) {
if (sctp_auth_init(ep, gfp))
goto nomem;
@@ -86,14 +86,14 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
INIT_LIST_HEAD(&ep->asocs);
/* Use SCTP specific send buffer space queues. */
- ep->sndbuf_policy = net->sctp.sndbuf_policy;
+ ep->sndbuf_policy = READ_ONCE(net->sctp.sndbuf_policy);
sk->sk_data_ready = sctp_data_ready;
sk->sk_write_space = sctp_write_space;
sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
/* Get the receive buffer policy for this endpoint */
- ep->rcvbuf_policy = net->sctp.rcvbuf_policy;
+ ep->rcvbuf_policy = READ_ONCE(net->sctp.rcvbuf_policy);
/* Generate the cookie authentication key. */
gen_cookie_auth_key(&ep->cookie_auth_key);
@@ -109,9 +109,9 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
/* Add the null key to the endpoint shared keys list and
* set the hmcas and chunks pointers.
*/
- ep->prsctp_enable = net->sctp.prsctp_enable;
- ep->reconf_enable = net->sctp.reconf_enable;
- ep->ecn_enable = net->sctp.ecn_enable;
+ ep->prsctp_enable = READ_ONCE(net->sctp.prsctp_enable);
+ ep->reconf_enable = READ_ONCE(net->sctp.reconf_enable);
+ ep->ecn_enable = READ_ONCE(net->sctp.ecn_enable);
/* Remember who we are attached to. */
ep->base.sk = sk;
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 9494cfa51106c..ecff82c0d5539 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -1276,7 +1276,7 @@ static struct sctp_association *__sctp_rcv_walk_lookup(struct net *net,
break;
case SCTP_CID_ASCONF:
- if (have_auth || net->sctp.addip_noauth)
+ if (have_auth || READ_ONCE(net->sctp.addip_noauth))
asoc = __sctp_rcv_asconf_lookup(
net, ch, laddr,
sctp_hdr(skb)->source,
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 90de272842512..43a757d4a69e7 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2038,7 +2038,7 @@ static int sctp_verify_ext_param(struct net *net,
* only if ADD-IP is turned on and we are not backward-compatible
* mode.
*/
- if (net->sctp.addip_noauth)
+ if (READ_ONCE(net->sctp.addip_noauth))
return 1;
if (ep->asconf_enable && !have_auth && have_asconf)
@@ -2425,7 +2425,7 @@ int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
* also give us an option to silently ignore the packet, which
* is what we'll do here.
*/
- if (!asoc->base.net->sctp.addip_noauth &&
+ if (!READ_ONCE(asoc->base.net->sctp.addip_noauth) &&
(asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
SCTP_PARAM_DEL_IP |
@@ -2583,7 +2583,7 @@ static int sctp_process_param(struct sctp_association *asoc,
break;
case SCTP_PARAM_COOKIE_PRESERVATIVE:
- if (!net->sctp.cookie_preserve_enable)
+ if (!READ_ONCE(net->sctp.cookie_preserve_enable))
break;
stale = ntohl(param.life->lifespan_increment);
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 35f540fb15fc1..01ee6c3dd441a 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -591,7 +591,7 @@ static void sctp_do_8_2_transport_strike(struct sctp_cmd_seq *commands,
* is SCTP_ACTIVE, then mark this transport as Partially Failed,
* see SCTP Quick Failover Draft, section 5.1
*/
- if (asoc->base.net->sctp.pf_enable &&
+ if (READ_ONCE(asoc->base.net->sctp.pf_enable) &&
transport->state == SCTP_ACTIVE &&
transport->error_count < transport->pathmaxrxt &&
transport->error_count > transport->pf_retrans) {
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index b2f609f177fb9..b6b95972eea9a 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -653,7 +653,7 @@ static bool sctp_auth_chunk_verify(struct net *net, struct sctp_chunk *chunk,
*/
/* Make sure that we and the peer are AUTH capable */
- if (!net->sctp.auth_enable || !asoc->peer.auth_capable)
+ if (!READ_ONCE(net->sctp.auth_enable) || !asoc->peer.auth_capable)
return false;
/* set-up our fake chunk so that we can process it */
@@ -3944,7 +3944,7 @@ enum sctp_disposition sctp_sf_do_asconf(struct net *net,
* described in [I-D.ietf-tsvwg-sctp-auth].
*/
if (!asoc->peer.asconf_capable ||
- (!net->sctp.addip_noauth && !chunk->auth))
+ (!READ_ONCE(net->sctp.addip_noauth) && !chunk->auth))
return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
hdr = (struct sctp_addiphdr *)chunk->skb->data;
@@ -4087,7 +4087,7 @@ enum sctp_disposition sctp_sf_do_asconf_ack(struct net *net,
* described in [I-D.ietf-tsvwg-sctp-auth].
*/
if (!asoc->peer.asconf_capable ||
- (!net->sctp.addip_noauth && !asconf_ack->auth))
+ (!READ_ONCE(net->sctp.addip_noauth) && !asconf_ack->auth))
return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
addip_hdr = (struct sctp_addiphdr *)asconf_ack->skb->data;
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index b5a57f61ee6d1..715ecc25b2866 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -403,7 +403,7 @@ static void sctp_auto_asconf_init(struct sctp_sock *sp)
{
struct net *net = sock_net(&sp->inet.sk);
- if (net->sctp.default_auto_asconf) {
+ if (READ_ONCE(net->sctp.default_auto_asconf)) {
spin_lock_bh(&net->sctp.addr_wq_lock);
list_add_tail(&sp->auto_asconf_list, &net->sctp.auto_asconf_splist);
spin_unlock_bh(&net->sctp.addr_wq_lock);
@@ -2326,6 +2326,7 @@ static int sctp_setsockopt_autoclose(struct sock *sk, u32 *optval,
{
struct sctp_sock *sp = sctp_sk(sk);
struct net *net = sock_net(sk);
+ unsigned long max_autoclose;
/* Applicable to UDP-style socket only */
if (sctp_style(sk, TCP))
@@ -2333,9 +2334,10 @@ static int sctp_setsockopt_autoclose(struct sock *sk, u32 *optval,
if (optlen != sizeof(int))
return -EINVAL;
+ max_autoclose = READ_ONCE(net->sctp.max_autoclose);
sp->autoclose = *optval;
- if (sp->autoclose > net->sctp.max_autoclose)
- sp->autoclose = net->sctp.max_autoclose;
+ if (sp->autoclose > max_autoclose)
+ sp->autoclose = max_autoclose;
return 0;
}
@@ -4296,7 +4298,7 @@ static int sctp_setsockopt_interleaving_supported(struct sock *sk,
if (!asoc && p->assoc_id != SCTP_FUTURE_ASSOC && sctp_style(sk, UDP))
return -EINVAL;
- if (!sock_net(sk)->sctp.intl_enable || !sp->frag_interleave) {
+ if (!READ_ONCE(sock_net(sk)->sctp.intl_enable) || !sp->frag_interleave) {
return -EPERM;
}
@@ -5098,9 +5100,9 @@ static int sctp_init_sock(struct sock *sk)
sp->default_timetolive = 0;
sp->default_rcv_context = 0;
- sp->max_burst = net->sctp.max_burst;
+ sp->max_burst = READ_ONCE(net->sctp.max_burst);
- sp->cookie_auth_enable = net->sctp.cookie_auth_enable;
+ sp->cookie_auth_enable = READ_ONCE(net->sctp.cookie_auth_enable);
/* Initialize default setup parameters. These parameters
* can be modified with the SCTP_INITMSG socket option or
@@ -5108,24 +5110,24 @@ static int sctp_init_sock(struct sock *sk)
*/
sp->initmsg.sinit_num_ostreams = sctp_max_outstreams;
sp->initmsg.sinit_max_instreams = sctp_max_instreams;
- sp->initmsg.sinit_max_attempts = net->sctp.max_retrans_init;
- sp->initmsg.sinit_max_init_timeo = net->sctp.rto_max;
+ sp->initmsg.sinit_max_attempts = READ_ONCE(net->sctp.max_retrans_init);
+ sp->initmsg.sinit_max_init_timeo = READ_ONCE(net->sctp.rto_max);
/* Initialize default RTO related parameters. These parameters can
* be modified for with the SCTP_RTOINFO socket option.
*/
- sp->rtoinfo.srto_initial = net->sctp.rto_initial;
- sp->rtoinfo.srto_max = net->sctp.rto_max;
- sp->rtoinfo.srto_min = net->sctp.rto_min;
+ sp->rtoinfo.srto_initial = READ_ONCE(net->sctp.rto_initial);
+ sp->rtoinfo.srto_max = READ_ONCE(net->sctp.rto_max);
+ sp->rtoinfo.srto_min = READ_ONCE(net->sctp.rto_min);
/* Initialize default association related parameters. These parameters
* can be modified with the SCTP_ASSOCINFO socket option.
*/
- sp->assocparams.sasoc_asocmaxrxt = net->sctp.max_retrans_association;
+ sp->assocparams.sasoc_asocmaxrxt = READ_ONCE(net->sctp.max_retrans_association);
sp->assocparams.sasoc_number_peer_destinations = 0;
sp->assocparams.sasoc_peer_rwnd = 0;
sp->assocparams.sasoc_local_rwnd = 0;
- sp->assocparams.sasoc_cookie_life = net->sctp.valid_cookie_life;
+ sp->assocparams.sasoc_cookie_life = READ_ONCE(net->sctp.valid_cookie_life);
/* Initialize default event subscriptions. By default, all the
* options are off.
@@ -5135,15 +5137,15 @@ static int sctp_init_sock(struct sock *sk)
/* Default Peer Address Parameters. These defaults can
* be modified via SCTP_PEER_ADDR_PARAMS
*/
- sp->hbinterval = net->sctp.hb_interval;
- sp->udp_port = htons(net->sctp.udp_port);
- sp->encap_port = htons(net->sctp.encap_port);
- sp->pathmaxrxt = net->sctp.max_retrans_path;
- sp->pf_retrans = net->sctp.pf_retrans;
- sp->ps_retrans = net->sctp.ps_retrans;
- sp->pf_expose = net->sctp.pf_expose;
+ sp->hbinterval = READ_ONCE(net->sctp.hb_interval);
+ sp->udp_port = htons(READ_ONCE(net->sctp.udp_port));
+ sp->encap_port = htons(READ_ONCE(net->sctp.encap_port));
+ sp->pathmaxrxt = READ_ONCE(net->sctp.max_retrans_path);
+ sp->pf_retrans = READ_ONCE(net->sctp.pf_retrans);
+ sp->ps_retrans = READ_ONCE(net->sctp.ps_retrans);
+ sp->pf_expose = READ_ONCE(net->sctp.pf_expose);
sp->pathmtu = 0; /* allow default discovery */
- sp->sackdelay = net->sctp.sack_timeout;
+ sp->sackdelay = READ_ONCE(net->sctp.sack_timeout);
sp->sackfreq = 2;
sp->param_flags = SPP_HB_ENABLE |
SPP_PMTUD_ENABLE |
@@ -5182,7 +5184,7 @@ static int sctp_init_sock(struct sock *sk)
atomic_set(&sp->pd_mode, 0);
skb_queue_head_init(&sp->pd_lobby);
sp->frag_interleave = 0;
- sp->probe_interval = net->sctp.probe_interval;
+ sp->probe_interval = READ_ONCE(net->sctp.probe_interval);
/* Create a per socket endpoint structure. Even if we
* change the data structure relationships, this may still
diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index 2b94c211427de..8a84ae3272d24 100644
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -402,11 +402,11 @@ static int proc_sctp_do_hmac_alg(const struct ctl_table *ctl, int write,
if (ret)
return ret;
if (!strcmp(tmp, "sha256")) {
- net->sctp.cookie_auth_enable = 1;
+ WRITE_ONCE(net->sctp.cookie_auth_enable, 1);
return 0;
}
if (!strcmp(tmp, "none")) {
- net->sctp.cookie_auth_enable = 0;
+ WRITE_ONCE(net->sctp.cookie_auth_enable, 0);
return 0;
}
return -EINVAL;
@@ -441,7 +441,7 @@ static int proc_sctp_do_rto_min(const struct ctl_table *ctl, int write,
if (new_value > max || new_value < min)
return -EINVAL;
- net->sctp.rto_min = new_value;
+ WRITE_ONCE(net->sctp.rto_min, new_value);
}
return ret;
@@ -469,7 +469,7 @@ static int proc_sctp_do_rto_max(const struct ctl_table *ctl, int write,
if (new_value > max || new_value < min)
return -EINVAL;
- net->sctp.rto_max = new_value;
+ WRITE_ONCE(net->sctp.rto_max, new_value);
}
return ret;
@@ -504,7 +504,7 @@ static int proc_sctp_do_auth(const struct ctl_table *ctl, int write,
if (write && ret == 0) {
struct sock *sk = net->sctp.ctl_sock;
- net->sctp.auth_enable = new_value;
+ WRITE_ONCE(net->sctp.auth_enable, new_value);
/* Update the value in the control socket */
lock_sock(sk);
sctp_sk(sk)->ep->auth_enable = new_value;
@@ -541,12 +541,12 @@ static int proc_sctp_do_udp_port(const struct ctl_table *ctl, int write,
return -EINVAL;
mutex_lock(&sctp_sysctl_mutex);
- net->sctp.udp_port = new_value;
+ WRITE_ONCE(net->sctp.udp_port, new_value);
sctp_udp_sock_stop(net);
if (new_value) {
ret = sctp_udp_sock_start(net);
if (ret)
- net->sctp.udp_port = 0;
+ WRITE_ONCE(net->sctp.udp_port, 0);
}
/* Update the value in the control socket */
@@ -580,7 +580,7 @@ static int proc_sctp_do_probe_interval(const struct ctl_table *ctl, int write,
if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
return -EINVAL;
- net->sctp.probe_interval = new_value;
+ WRITE_ONCE(net->sctp.probe_interval, new_value);
}
return ret;
diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 6ea55b9fbde45..78b87e1b7e64b 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -55,7 +55,7 @@ static void sctp_transport_init(struct net *net,
* given destination transport address, set RTO to the protocol
* parameter 'RTO.Initial'.
*/
- peer->rto = msecs_to_jiffies(net->sctp.rto_initial);
+ peer->rto = msecs_to_jiffies(READ_ONCE(net->sctp.rto_initial));
peer->last_time_heard = 0;
peer->last_time_ecne_reduced = jiffies;
@@ -65,8 +65,8 @@ static void sctp_transport_init(struct net *net,
SPP_SACKDELAY_ENABLE;
/* Initialize the default path max_retrans. */
- peer->pathmaxrxt = net->sctp.max_retrans_path;
- peer->pf_retrans = net->sctp.pf_retrans;
+ peer->pathmaxrxt = READ_ONCE(net->sctp.max_retrans_path);
+ peer->pf_retrans = READ_ONCE(net->sctp.pf_retrans);
INIT_LIST_HEAD(&peer->transmitted);
INIT_LIST_HEAD(&peer->send_ready);
--
2.43.0