[SCTP]: Honor flags when setting peer address parameters

Parameters only take effect when a corresponding flag bit is set
and a value is specified. This means we need to check the flags
in addition to checking for non-zero value.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 52 insertions, 17 deletions

diff --git a/include/net/sctp/user.h b/include/net/sctp/user.h
index 4ed752119bbc..80b7afea17fc 100644
--- a/include/net/sctp/user.h
+++ b/include/net/sctp/user.h
@@ -513,16 +513,17 @@ struct sctp_setadaptation {
  *   address's parameters:
  */
 enum  sctp_spp_flags {
-        SPP_HB_ENABLE = 1,              /*Enable heartbeats*/
-        SPP_HB_DISABLE = 2,             /*Disable heartbeats*/
+        SPP_HB_ENABLE = 1<<0,           /*Enable heartbeats*/
+        SPP_HB_DISABLE = 1<<1,          /*Disable heartbeats*/
         SPP_HB = SPP_HB_ENABLE | SPP_HB_DISABLE,
-        SPP_HB_DEMAND = 4,              /*Send heartbeat immediately*/
-        SPP_PMTUD_ENABLE = 8,           /*Enable PMTU discovery*/
-        SPP_PMTUD_DISABLE = 16,         /*Disable PMTU discovery*/
+        SPP_HB_DEMAND = 1<<2,           /*Send heartbeat immediately*/
+        SPP_PMTUD_ENABLE = 1<<3,        /*Enable PMTU discovery*/
+        SPP_PMTUD_DISABLE = 1<<4,       /*Disable PMTU discovery*/
         SPP_PMTUD = SPP_PMTUD_ENABLE | SPP_PMTUD_DISABLE,
-        SPP_SACKDELAY_ENABLE = 32,      /*Enable SACK*/
-        SPP_SACKDELAY_DISABLE = 64,     /*Disable SACK*/
+        SPP_SACKDELAY_ENABLE = 1<<5,    /*Enable SACK*/
+        SPP_SACKDELAY_DISABLE = 1<<6,   /*Disable SACK*/
         SPP_SACKDELAY = SPP_SACKDELAY_ENABLE | SPP_SACKDELAY_DISABLE,
+        SPP_HB_TIME_IS_ZERO = 1<<7,     /* Set HB delay to 0 */
 };
 
 struct sctp_paddrparams {
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 1e787a2d0b5f..dda2f6700f5b 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2039,6 +2039,10 @@ static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
  *                     to be made immediately.
  *
+ *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
+ *                     heartbeat delayis to be set to the value of 0
+ *                     milliseconds.
+ *
  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
  *                     discovery upon the specified address. Note that
  *                     if the address feild is empty then all addresses
@@ -2081,13 +2085,30 @@ static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
                         return error;
         }
 
-        if (params->spp_hbinterval) {
-                if (trans) {
-                        trans->hbinterval = msecs_to_jiffies(params->spp_hbinterval);
-                } else if (asoc) {
-                        asoc->hbinterval = msecs_to_jiffies(params->spp_hbinterval);
-                } else {
-                        sp->hbinterval = params->spp_hbinterval;
+        /* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
+         * this field is ignored.  Note also that a value of zero indicates
+         * the current setting should be left unchanged.
+         */
+        if (params->spp_flags & SPP_HB_ENABLE) {
+
+                /* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
+                 * set.  This lets us use 0 value when this flag
+                 * is set.
+                 */
+                if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
+                        params->spp_hbinterval = 0;
+
+                if (params->spp_hbinterval ||
+                    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
+                        if (trans) {
+                                trans->hbinterval =
+                                    msecs_to_jiffies(params->spp_hbinterval);
+                        } else if (asoc) {
+                                asoc->hbinterval =
+                                    msecs_to_jiffies(params->spp_hbinterval);
+                        } else {
+                                sp->hbinterval = params->spp_hbinterval;
+                        }
                 }
         }
 
@@ -2104,7 +2125,12 @@ static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
                 }
         }
 
-        if (params->spp_pathmtu) {
+        /* When Path MTU discovery is disabled the value specified here will
+         * be the "fixed" path mtu (i.e. the value of the spp_flags field must
+         * include the flag SPP_PMTUD_DISABLE for this field to have any
+         * effect).
+         */
+        if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
                 if (trans) {
                         trans->pathmtu = params->spp_pathmtu;
                         sctp_assoc_sync_pmtu(asoc);
@@ -2135,7 +2161,11 @@ static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
                 }
         }
 
-        if (params->spp_sackdelay) {
+        /* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
+         * value of this field is ignored.  Note also that a value of zero
+         * indicates the current setting should be left unchanged.
+         */
+        if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
                 if (trans) {
                         trans->sackdelay =
                                 msecs_to_jiffies(params->spp_sackdelay);
@@ -2163,7 +2193,11 @@ static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
                 }
         }
 
-        if (params->spp_pathmaxrxt) {
+        /* Note that unless the spp_flag is set to SPP_PMTUD_ENABLE the value
+         * of this field is ignored.  Note also that a value of zero
+         * indicates the current setting should be left unchanged.
+         */
+        if ((params->spp_flags & SPP_PMTUD_ENABLE) && params->spp_pathmaxrxt) {
                 if (trans) {
                         trans->pathmaxrxt = params->spp_pathmaxrxt;
                 } else if (asoc) {