xfrm: Fix aevent generation for each received packet
If asynchronous events are enabled for a particular netlink socket,
the notify function is called by the advance function. The notify
function creates and dispatches a km_event if a replay timeout occurred,
or at least replay_maxdiff packets have been received since the last
asynchronous event has been sent. The function is supposed to return if
neither of the two events were detected for a state, or replay_maxdiff
is equal to zero.
Replay_maxdiff is initialized in xfrm_state_construct to the value of
the xfrm.sysctl_aevent_rseqth (2 by default), and updated if for a state
if the netlink attribute XFRMA_REPLAY_THRESH is set.
If, however, replay_maxdiff is set to zero, then all of the three notify
implementations perform a break from the switch statement instead of
checking whether a timeout occurred, and -- if not -- return. As a
result an asynchronous event is generated for every replay update of a
state that has a zero replay_maxdiff value.
This patch modifies the notify functions such that they immediately
return if replay_maxdiff has the value zero, unless a timeout occurred.
Signed-off-by: Thomas Egerer <thomas.egerer@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index eeca388..dab57da 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -61,9 +61,9 @@
switch (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)) {
+ if (!x->replay_maxdiff ||
+ ((x->replay.seq - x->preplay.seq < x->replay_maxdiff) &&
+ (x->replay.oseq - x->preplay.oseq < x->replay_maxdiff))) {
if (x->xflags & XFRM_TIME_DEFER)
event = XFRM_REPLAY_TIMEOUT;
else
@@ -301,9 +301,10 @@
switch (event) {
case XFRM_REPLAY_UPDATE:
- if (x->replay_maxdiff &&
- (replay_esn->seq - preplay_esn->seq < x->replay_maxdiff) &&
- (replay_esn->oseq - preplay_esn->oseq < x->replay_maxdiff)) {
+ if (!x->replay_maxdiff ||
+ ((replay_esn->seq - preplay_esn->seq < x->replay_maxdiff) &&
+ (replay_esn->oseq - preplay_esn->oseq
+ < x->replay_maxdiff))) {
if (x->xflags & XFRM_TIME_DEFER)
event = XFRM_REPLAY_TIMEOUT;
else
@@ -352,28 +353,30 @@
switch (event) {
case XFRM_REPLAY_UPDATE:
- if (!x->replay_maxdiff)
- break;
-
- if (replay_esn->seq_hi == preplay_esn->seq_hi)
- seq_diff = replay_esn->seq - preplay_esn->seq;
- else
- seq_diff = ~preplay_esn->seq + replay_esn->seq + 1;
-
- if (replay_esn->oseq_hi == preplay_esn->oseq_hi)
- oseq_diff = replay_esn->oseq - preplay_esn->oseq;
- else
- oseq_diff = ~preplay_esn->oseq + replay_esn->oseq + 1;
-
- if (seq_diff < x->replay_maxdiff &&
- oseq_diff < x->replay_maxdiff) {
-
- if (x->xflags & XFRM_TIME_DEFER)
- event = XFRM_REPLAY_TIMEOUT;
+ if (x->replay_maxdiff) {
+ if (replay_esn->seq_hi == preplay_esn->seq_hi)
+ seq_diff = replay_esn->seq - preplay_esn->seq;
else
- return;
+ seq_diff = ~preplay_esn->seq + replay_esn->seq
+ + 1;
+
+ if (replay_esn->oseq_hi == preplay_esn->oseq_hi)
+ oseq_diff = replay_esn->oseq
+ - preplay_esn->oseq;
+ else
+ oseq_diff = ~preplay_esn->oseq
+ + replay_esn->oseq + 1;
+
+ if (seq_diff >= x->replay_maxdiff ||
+ oseq_diff >= x->replay_maxdiff)
+ break;
}
+ if (x->xflags & XFRM_TIME_DEFER)
+ event = XFRM_REPLAY_TIMEOUT;
+ else
+ return;
+
break;
case XFRM_REPLAY_TIMEOUT: