From cd808fc9a6c7cd3a4311d9d2cffc4adbeaef5f6c Mon Sep 17 00:00:00 2001 From: Thomas Egerer Date: Thu, 19 Sep 2013 13:19:19 +0200 Subject: 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 Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_replay.c | 51 ++++++++++++++++++++++++++------------------------ 1 file changed, 27 insertions(+), 24 deletions(-) (limited to 'net') diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c index eeca388effc..dab57daae40 100644 --- a/net/xfrm/xfrm_replay.c +++ b/net/xfrm/xfrm_replay.c @@ -61,9 +61,9 @@ static void xfrm_replay_notify(struct xfrm_state *x, int event) 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 @@ static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event) 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 @@ static void xfrm_replay_notify_esn(struct xfrm_state *x, int event) 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->replay_maxdiff) { + 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 (x->xflags & XFRM_TIME_DEFER) - event = XFRM_REPLAY_TIMEOUT; + if (replay_esn->oseq_hi == preplay_esn->oseq_hi) + oseq_diff = replay_esn->oseq + - preplay_esn->oseq; else - return; + 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: -- cgit v1.2.3