10 files changed, 71 insertions, 39 deletions

diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index ab2791b3189d..64f203c45378 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -715,6 +715,7 @@ enum {
         NET_SCTP_PRSCTP_ENABLE           = 14,
         NET_SCTP_SNDBUF_POLICY           = 15,
         NET_SCTP_SACK_TIMEOUT            = 16,
+        NET_SCTP_RCVBUF_POLICY           = 17,
 };
 
 /* /proc/sys/net/bridge */
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 2aad4468797e..8e7794ee27ff 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -161,6 +161,13 @@ extern struct sctp_globals {
          */
         int sndbuf_policy;
 
+        /*
+         * Policy for preforming sctp/socket accounting
+         * 0   - do socket level accounting, all assocs share sk_rcvbuf
+         * 1   - do sctp accounting, each asoc may use sk_rcvbuf bytes
+         */
+        int rcvbuf_policy;
+
         /* Delayed SACK timeout  200ms default*/
         int sack_timeout;
 
@@ -218,6 +225,7 @@ extern struct sctp_globals {
 #define sctp_cookie_preserve_enable     (sctp_globals.cookie_preserve_enable)
 #define sctp_max_retrans_association    (sctp_globals.max_retrans_association)
 #define sctp_sndbuf_policy              (sctp_globals.sndbuf_policy)
+#define sctp_rcvbuf_policy              (sctp_globals.rcvbuf_policy)
 #define sctp_max_retrans_path           (sctp_globals.max_retrans_path)
 #define sctp_max_retrans_init           (sctp_globals.max_retrans_init)
 #define sctp_sack_timeout               (sctp_globals.sack_timeout)
@@ -1224,6 +1232,9 @@ struct sctp_endpoint {
 
         /* sendbuf acct. policy.        */
         __u32 sndbuf_policy;
+
+        /* rcvbuf acct. policy. */
+        __u32 rcvbuf_policy;
 };
 
 /* Recover the outter endpoint structure. */
@@ -1550,6 +1561,11 @@ struct sctp_association {
          */
         int sndbuf_used;
 
+        /* This is the amount of memory that this association has allocated
+         * in the receive path at any given time.
+         */
+        atomic_t rmem_alloc;
+
         /* This is the wait queue head for send requests waiting on
          * the association sndbuf space.
          */
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 5f07ddb19554..dec68a604773 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -177,10 +177,10 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
          * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
          * 1500 bytes in one SCTP packet.
          */
-        if (sk->sk_rcvbuf < SCTP_DEFAULT_MINWINDOW)
+        if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
                 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
         else
-                asoc->rwnd = sk->sk_rcvbuf;
+                asoc->rwnd = sk->sk_rcvbuf/2;
 
         asoc->a_rwnd = asoc->rwnd;
 
@@ -192,6 +192,9 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
         /* Set the sndbuf size for transmit.  */
         asoc->sndbuf_used = 0;
 
+        /* Initialize the receive memory counter */
+        atomic_set(&asoc->rmem_alloc, 0);
+
         init_waitqueue_head(&asoc->wait);
 
         asoc->c.my_vtag = sctp_generate_tag(ep);
@@ -400,6 +403,8 @@ static void sctp_association_destroy(struct sctp_association *asoc)
                 spin_unlock_bh(&sctp_assocs_id_lock);
         }
 
+        BUG_TRAP(!atomic_read(&asoc->rmem_alloc));
+
         if (asoc->base.malloced) {
                 kfree(asoc);
                 SCTP_DBG_OBJCNT_DEC(assoc);
diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c
index 0df76897f563..67bd53070ee0 100644
--- a/net/sctp/endpointola.c
+++ b/net/sctp/endpointola.c
@@ -104,6 +104,9 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
         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 = sctp_rcvbuf_policy;
+
         /* Initialize the secret key used with cookie. */
         get_random_bytes(&ep->secret_key[0], SCTP_SECRET_SIZE);
         ep->last_key = ep->current_key = 0;
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 28f32243397f..b24ff2c1aef5 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -100,21 +100,6 @@ static inline int sctp_rcv_checksum(struct sk_buff *skb)
         return 0;
 }
 
-/* The free routine for skbuffs that sctp receives */
-static void sctp_rfree(struct sk_buff *skb)
-{
-        atomic_sub(sizeof(struct sctp_chunk),&skb->sk->sk_rmem_alloc);
-        sock_rfree(skb);
-}
-
-/* The ownership wrapper routine to do receive buffer accounting */
-static void sctp_rcv_set_owner_r(struct sk_buff *skb, struct sock *sk)
-{
-        skb_set_owner_r(skb,sk);
-        skb->destructor = sctp_rfree;
-        atomic_add(sizeof(struct sctp_chunk),&sk->sk_rmem_alloc);
-}
-
 struct sctp_input_cb {
         union {
                 struct inet_skb_parm    h4;
@@ -217,9 +202,6 @@ int sctp_rcv(struct sk_buff *skb)
                 rcvr = &ep->base;
         }
 
-        if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
-                goto discard_release;
-
         /*
          * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
          * An SCTP packet is called an "out of the blue" (OOTB)
@@ -256,8 +238,6 @@ int sctp_rcv(struct sk_buff *skb)
         }
         SCTP_INPUT_CB(skb)->chunk = chunk;
 
-        sctp_rcv_set_owner_r(skb,sk);
-
         /* Remember what endpoint is to handle this packet. */
         chunk->rcvr = rcvr;
 
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index dc9dff396fad..f775d78aa59d 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -1050,6 +1050,9 @@ SCTP_STATIC __init int sctp_init(void)
         /* Sendbuffer growth        - do per-socket accounting */
         sctp_sndbuf_policy              = 0;
 
+        /* Rcvbuffer growth         - do per-socket accounting */
+        sctp_rcvbuf_policy              = 0;
+
         /* HB.interval              - 30 seconds */
         sctp_hb_interval                = SCTP_DEFAULT_TIMEOUT_HEARTBEAT;
 
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 505c7de10c50..475bfb4972d9 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -5160,6 +5160,8 @@ static int sctp_eat_data(const struct sctp_association *asoc,
         sctp_verb_t deliver;
         int tmp;
         __u32 tsn;
+        int account_value;
+        struct sock *sk = asoc->base.sk;
 
         data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data;
         skb_pull(chunk->skb, sizeof(sctp_datahdr_t));
@@ -5169,6 +5171,26 @@ static int sctp_eat_data(const struct sctp_association *asoc,
 
         /* ASSERT:  Now skb->data is really the user data.  */
 
+        /*
+         * if we are established, and we have used up our receive
+         * buffer memory, drop the frame
+         */
+        if (asoc->state == SCTP_STATE_ESTABLISHED) {
+                /*
+                 * If the receive buffer policy is 1, then each
+                 * association can allocate up to sk_rcvbuf bytes
+                 * otherwise, all the associations in aggregate
+                 * may allocate up to sk_rcvbuf bytes
+                 */
+                if (asoc->ep->rcvbuf_policy)
+                        account_value = atomic_read(&asoc->rmem_alloc);
+                else
+                        account_value = atomic_read(&sk->sk_rmem_alloc);
+
+                if (account_value > sk->sk_rcvbuf)
+                        return SCTP_IERROR_IGNORE_TSN;
+        }
+
         /* Process ECN based congestion.
          *
          * Since the chunk structure is reused for all chunks within
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 4d1b8d8904c4..abab81f3818f 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -5114,8 +5114,10 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
         sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
                 event = sctp_skb2event(skb);
                 if (event->asoc == assoc) {
+                        sock_rfree(skb);
                         __skb_unlink(skb, &oldsk->sk_receive_queue);
                         __skb_queue_tail(&newsk->sk_receive_queue, skb);
+                        skb_set_owner_r(skb, newsk);
                 }
         }
 
@@ -5143,8 +5145,10 @@ static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
                 sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
                         event = sctp_skb2event(skb);
                         if (event->asoc == assoc) {
+                                sock_rfree(skb);
                                 __skb_unlink(skb, &oldsp->pd_lobby);
                                 __skb_queue_tail(queue, skb);
+                                skb_set_owner_r(skb, newsk);
                         }
                 }
 
diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index 75b28dd634fe..fcd7096c953d 100644
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -121,6 +121,14 @@ static ctl_table sctp_table[] = {
                 .proc_handler   = &proc_dointvec
         },
         {
+                .ctl_name       = NET_SCTP_RCVBUF_POLICY,
+                .procname       = "rcvbuf_policy",
+                .data           = &sctp_rcvbuf_policy,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        {
                 .ctl_name       = NET_SCTP_PATH_MAX_RETRANS,
                 .procname       = "path_max_retrans",
                 .data           = &sctp_max_retrans_path,
diff --git a/net/sctp/ulpevent.c b/net/sctp/ulpevent.c
index e049f41faa47..ba97f974f57c 100644
--- a/net/sctp/ulpevent.c
+++ b/net/sctp/ulpevent.c
@@ -52,19 +52,6 @@ static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
                                        struct sctp_association *asoc);
 static void sctp_ulpevent_release_data(struct sctp_ulpevent *event);
 
-/* Stub skb destructor.  */
-static void sctp_stub_rfree(struct sk_buff *skb)
-{
-/* WARNING:  This function is just a warning not to use the
- * skb destructor.  If the skb is shared, we may get the destructor
- * callback on some processor that does not own the sock_lock.  This
- * was occuring with PACKET socket applications that were monitoring
- * our skbs.   We can't take the sock_lock, because we can't risk
- * recursing if we do really own the sock lock.  Instead, do all
- * of our rwnd manipulation while we own the sock_lock outright.
- */
-}
-
 /* Initialize an ULP event from an given skb.  */
 SCTP_STATIC void sctp_ulpevent_init(struct sctp_ulpevent *event, int msg_flags)
 {
@@ -111,15 +98,19 @@ static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
          */
         sctp_association_hold((struct sctp_association *)asoc);
         skb = sctp_event2skb(event);
-        skb->sk = asoc->base.sk;
         event->asoc = (struct sctp_association *)asoc;
-        skb->destructor = sctp_stub_rfree;
+        atomic_add(skb->truesize, &event->asoc->rmem_alloc);
+        skb_set_owner_r(skb, asoc->base.sk);
 }
 
 /* A simple destructor to give up the reference to the association. */
 static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
 {
-        sctp_association_put(event->asoc);
+        struct sctp_association *asoc = event->asoc;
+        struct sk_buff *skb = sctp_event2skb(event);
+
+        atomic_sub(skb->truesize, &asoc->rmem_alloc);
+        sctp_association_put(asoc);
 }
 
 /* Create and initialize an SCTP_ASSOC_CHANGE event.
@@ -922,7 +913,6 @@ done:
 /* Free a ulpevent that has an owner.  It includes releasing the reference
  * to the owner, updating the rwnd in case of a DATA event and freeing the
  * skb.
- * See comments in sctp_stub_rfree().
  */
 void sctp_ulpevent_free(struct sctp_ulpevent *event)
 {