Fix unexpected SA hard expiration after changing date

After SA is setup, one timer is armed to detect soft/hard expiration,
however the timer handler uses xtime to do the math. This makes hard
expiration occurs first before soft expiration after setting new date
with big interval. As a result new child SA is deleted before rekeying
the new one.

Signed-off-by: Fan Du <fdu@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index d9509eb..62b619e 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -213,6 +213,9 @@
 	struct xfrm_lifetime_cur curlft;
 	struct tasklet_hrtimer	mtimer;
 
+	/* used to fix curlft->add_time when changing date */
+	long		saved_tmo;
+
 	/* Last used time */
 	unsigned long		lastused;
 
@@ -238,6 +241,7 @@
 
 /* xflags - make enum if more show up */
 #define XFRM_TIME_DEFER	1
+#define XFRM_SOFT_EXPIRE 2
 
 enum {
 	XFRM_STATE_VOID,