[XFRM]: Fix aevent timer.

Send aevent immediately if we have sent nothing since last timer and
this is the first packet.

Fixes a corner case when packet threshold is very high, the timer low
and a very low packet rate input which is bursty.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 27 insertions, 6 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 0d5529c382e8..afa508d92c93 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -143,6 +143,11 @@ struct xfrm_state
         /* Replay detection state at the time we sent the last notification */
         struct xfrm_replay_state preplay;
 
+        /* internal flag that only holds state for delayed aevent at the
+         * moment
+        */
+        u32                     xflags;
+
         /* Replay detection notification settings */
         u32                     replay_maxage;
         u32                     replay_maxdiff;
@@ -168,6 +173,9 @@ struct xfrm_state
         void                    *data;
 };
 
+/* xflags - make enum if more show up */
+#define XFRM_TIME_DEFER 1
+
 enum {
         XFRM_STATE_VOID,
         XFRM_STATE_ACQ,
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index a8e14dc1b04e..3dc3e1f3b7aa 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -805,16 +805,22 @@ void xfrm_replay_notify(struct xfrm_state *x, int event)
         case XFRM_REPLAY_UPDATE:
                 if (x->replay_maxdiff &&
                     (x->replay.seq - x->preplay.seq < x->replay_maxdiff) &&
-                    (x->replay.oseq - x->preplay.oseq < x->replay_maxdiff))
-                        return;
+                    (x->replay.oseq - x->preplay.oseq < x->replay_maxdiff)) {
+                        if (x->xflags & XFRM_TIME_DEFER)
+                                event = XFRM_REPLAY_TIMEOUT;
+                        else
+                                return;
+                }
 
                 break;
 
         case XFRM_REPLAY_TIMEOUT:
                 if ((x->replay.seq == x->preplay.seq) &&
                     (x->replay.bitmap == x->preplay.bitmap) &&
-                    (x->replay.oseq == x->preplay.oseq))
+                    (x->replay.oseq == x->preplay.oseq)) {
+                        x->xflags |= XFRM_TIME_DEFER;
                         return;
+                }
 
                 break;
         }
@@ -825,8 +831,10 @@ void xfrm_replay_notify(struct xfrm_state *x, int event)
         km_state_notify(x, &c);
 
         if (x->replay_maxage &&
-            !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
+            !mod_timer(&x->rtimer, jiffies + x->replay_maxage)) {
                 xfrm_state_hold(x);
+                x->xflags &= ~XFRM_TIME_DEFER;
+        }
 }
 EXPORT_SYMBOL(xfrm_replay_notify);
 
@@ -836,10 +844,15 @@ static void xfrm_replay_timer_handler(unsigned long data)
 
         spin_lock(&x->lock);
 
-        if (xfrm_aevent_is_on() && x->km.state == XFRM_STATE_VALID)
-                xfrm_replay_notify(x, XFRM_REPLAY_TIMEOUT);
+        if (x->km.state == XFRM_STATE_VALID) {
+                if (xfrm_aevent_is_on())
+                        xfrm_replay_notify(x, XFRM_REPLAY_TIMEOUT);
+                else
+                        x->xflags |= XFRM_TIME_DEFER;
+        }
 
         spin_unlock(&x->lock);
+        xfrm_state_put(x);
 }
 
 int xfrm_replay_check(struct xfrm_state *x, u32 seq)