[PATCH] net: sctp: Convert timers to use timer_setup()

From: Kees Cook
Date: Tue Oct 24 2017 - 04:45:44 EST


In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Vlad Yasevich <vyasevich@xxxxxxxxx>
Cc: Neil Horman <nhorman@xxxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: linux-sctp@xxxxxxxxxxxxxxx
Cc: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
include/net/sctp/sm.h | 10 +++---
net/sctp/associola.c | 3 +-
net/sctp/protocol.c | 7 ++--
net/sctp/sm_sideeffect.c | 85 +++++++++++++++++++++++++++++-------------------
net/sctp/transport.c | 13 +++-----
5 files changed, 66 insertions(+), 52 deletions(-)

diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h
index 2db3d3a9ce1d..13cc4963e905 100644
--- a/include/net/sctp/sm.h
+++ b/include/net/sctp/sm.h
@@ -72,7 +72,7 @@ typedef enum sctp_disposition (sctp_state_fn_t) (
const union sctp_subtype type,
void *arg,
struct sctp_cmd_seq *commands);
-typedef void (sctp_timer_event_t) (unsigned long);
+typedef void (sctp_timer_event_t) (struct timer_list *);
struct sctp_sm_table_entry {
sctp_state_fn_t *fn;
const char *name;
@@ -314,10 +314,10 @@ int sctp_do_sm(struct net *net, enum sctp_event event_type,
void *event_arg, gfp_t gfp);

/* 2nd level prototypes */
-void sctp_generate_t3_rtx_event(unsigned long peer);
-void sctp_generate_heartbeat_event(unsigned long peer);
-void sctp_generate_reconf_event(unsigned long peer);
-void sctp_generate_proto_unreach_event(unsigned long peer);
+void sctp_generate_t3_rtx_event(struct timer_list *t);
+void sctp_generate_heartbeat_event(struct timer_list *t);
+void sctp_generate_reconf_event(struct timer_list *t);
+void sctp_generate_proto_unreach_event(struct timer_list *t);

void sctp_ootb_pkt_free(struct sctp_packet *packet);

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index dfb9651e818b..69394f4d6091 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -149,8 +149,7 @@ static struct sctp_association *sctp_association_init(

/* Initializes the timers */
for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
- setup_timer(&asoc->timers[i], sctp_timer_events[i],
- (unsigned long)asoc);
+ timer_setup(&asoc->timers[i], sctp_timer_events[i], 0);

/* Pull default initialization values from the sock options.
* Note: This assumes that the values have already been
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index fcd80feb293f..f5172c21349b 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -622,9 +622,9 @@ static void sctp_v4_ecn_capable(struct sock *sk)
INET_ECN_xmit(sk);
}

-static void sctp_addr_wq_timeout_handler(unsigned long arg)
+static void sctp_addr_wq_timeout_handler(struct timer_list *t)
{
- struct net *net = (struct net *)arg;
+ struct net *net = from_timer(net, t, sctp.addr_wq_timer);
struct sctp_sockaddr_entry *addrw, *temp;
struct sctp_sock *sp;

@@ -1304,8 +1304,7 @@ static int __net_init sctp_defaults_init(struct net *net)
INIT_LIST_HEAD(&net->sctp.auto_asconf_splist);
spin_lock_init(&net->sctp.addr_wq_lock);
net->sctp.addr_wq_timer.expires = 0;
- setup_timer(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler,
- (unsigned long)net);
+ timer_setup(&net->sctp.addr_wq_timer, sctp_addr_wq_timeout_handler, 0);

return 0;

diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 402bfbb888cd..1c2699b424af 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -243,9 +243,10 @@ static int sctp_gen_sack(struct sctp_association *asoc, int force,
/* When the T3-RTX timer expires, it calls this function to create the
* relevant state machine event.
*/
-void sctp_generate_t3_rtx_event(unsigned long peer)
+void sctp_generate_t3_rtx_event(struct timer_list *t)
{
- struct sctp_transport *transport = (struct sctp_transport *) peer;
+ struct sctp_transport *transport =
+ from_timer(transport, t, T3_rtx_timer);
struct sctp_association *asoc = transport->asoc;
struct sock *sk = asoc->base.sk;
struct net *net = sock_net(sk);
@@ -319,50 +320,63 @@ static void sctp_generate_timeout_event(struct sctp_association *asoc,
sctp_association_put(asoc);
}

-static void sctp_generate_t1_cookie_event(unsigned long data)
+static void sctp_generate_t1_cookie_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *) data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
+
sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
}

-static void sctp_generate_t1_init_event(unsigned long data)
+static void sctp_generate_t1_init_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *) data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_INIT]);
+
sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
}

-static void sctp_generate_t2_shutdown_event(unsigned long data)
+static void sctp_generate_t2_shutdown_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *) data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN]);
+
sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
}

-static void sctp_generate_t4_rto_event(unsigned long data)
+static void sctp_generate_t4_rto_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *) data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T4_RTO]);
+
sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
}

-static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
+static void sctp_generate_t5_shutdown_guard_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *)data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t,
+ timers[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]);
+
sctp_generate_timeout_event(asoc,
SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);

} /* sctp_generate_t5_shutdown_guard_event() */

-static void sctp_generate_autoclose_event(unsigned long data)
+static void sctp_generate_autoclose_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *) data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE]);
+
sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
}

/* Generate a heart beat event. If the sock is busy, reschedule. Make
* sure that the transport is still valid.
*/
-void sctp_generate_heartbeat_event(unsigned long data)
+void sctp_generate_heartbeat_event(struct timer_list *t)
{
- struct sctp_transport *transport = (struct sctp_transport *) data;
+ struct sctp_transport *transport = from_timer(transport, t, hb_timer);
struct sctp_association *asoc = transport->asoc;
struct sock *sk = asoc->base.sk;
struct net *net = sock_net(sk);
@@ -405,9 +419,10 @@ void sctp_generate_heartbeat_event(unsigned long data)
/* Handle the timeout of the ICMP protocol unreachable timer. Trigger
* the correct state machine transition that will close the association.
*/
-void sctp_generate_proto_unreach_event(unsigned long data)
+void sctp_generate_proto_unreach_event(struct timer_list *t)
{
- struct sctp_transport *transport = (struct sctp_transport *)data;
+ struct sctp_transport *transport =
+ from_timer(transport, t, proto_unreach_timer);
struct sctp_association *asoc = transport->asoc;
struct sock *sk = asoc->base.sk;
struct net *net = sock_net(sk);
@@ -439,9 +454,10 @@ void sctp_generate_proto_unreach_event(unsigned long data)
}

/* Handle the timeout of the RE-CONFIG timer. */
-void sctp_generate_reconf_event(unsigned long data)
+void sctp_generate_reconf_event(struct timer_list *t)
{
- struct sctp_transport *transport = (struct sctp_transport *)data;
+ struct sctp_transport *transport =
+ from_timer(transport, t, reconf_timer);
struct sctp_association *asoc = transport->asoc;
struct sock *sk = asoc->base.sk;
struct net *net = sock_net(sk);
@@ -471,24 +487,27 @@ void sctp_generate_reconf_event(unsigned long data)
}

/* Inject a SACK Timeout event into the state machine. */
-static void sctp_generate_sack_event(unsigned long data)
+static void sctp_generate_sack_event(struct timer_list *t)
{
- struct sctp_association *asoc = (struct sctp_association *)data;
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_SACK]);
+
sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
}

sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
- NULL,
- sctp_generate_t1_cookie_event,
- sctp_generate_t1_init_event,
- sctp_generate_t2_shutdown_event,
- NULL,
- sctp_generate_t4_rto_event,
- sctp_generate_t5_shutdown_guard_event,
- NULL,
- NULL,
- sctp_generate_sack_event,
- sctp_generate_autoclose_event,
+ [SCTP_EVENT_TIMEOUT_NONE] = NULL,
+ [SCTP_EVENT_TIMEOUT_T1_COOKIE] = sctp_generate_t1_cookie_event,
+ [SCTP_EVENT_TIMEOUT_T1_INIT] = sctp_generate_t1_init_event,
+ [SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = sctp_generate_t2_shutdown_event,
+ [SCTP_EVENT_TIMEOUT_T3_RTX] = NULL,
+ [SCTP_EVENT_TIMEOUT_T4_RTO] = sctp_generate_t4_rto_event,
+ [SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] =
+ sctp_generate_t5_shutdown_guard_event,
+ [SCTP_EVENT_TIMEOUT_HEARTBEAT] = NULL,
+ [SCTP_EVENT_TIMEOUT_RECONF] = NULL,
+ [SCTP_EVENT_TIMEOUT_SACK] = sctp_generate_sack_event,
+ [SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sctp_generate_autoclose_event,
};


diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 2d9bd3776bc8..1e5a22430cf5 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -87,14 +87,11 @@ static struct sctp_transport *sctp_transport_init(struct net *net,
INIT_LIST_HEAD(&peer->send_ready);
INIT_LIST_HEAD(&peer->transports);

- setup_timer(&peer->T3_rtx_timer, sctp_generate_t3_rtx_event,
- (unsigned long)peer);
- setup_timer(&peer->hb_timer, sctp_generate_heartbeat_event,
- (unsigned long)peer);
- setup_timer(&peer->reconf_timer, sctp_generate_reconf_event,
- (unsigned long)peer);
- setup_timer(&peer->proto_unreach_timer,
- sctp_generate_proto_unreach_event, (unsigned long)peer);
+ timer_setup(&peer->T3_rtx_timer, sctp_generate_t3_rtx_event, 0);
+ timer_setup(&peer->hb_timer, sctp_generate_heartbeat_event, 0);
+ timer_setup(&peer->reconf_timer, sctp_generate_reconf_event, 0);
+ timer_setup(&peer->proto_unreach_timer,
+ sctp_generate_proto_unreach_event, 0);

/* Initialize the 64-bit random nonce sent with heartbeat. */
get_random_bytes(&peer->hb_nonce, sizeof(peer->hb_nonce));
--
2.7.4


--
Kees Cook
Pixel Security