xfrm: removes a superfluous check and add a statistic

Remove the check if x->km.state equal to XFRM_STATE_VALID in
xfrm_state_check_expire(), which will be done before call
xfrm_state_check_expire().

add a LINUX_MIB_XFRMOUTSTATEINVALID statistic to record the
outbound error due to invalid xfrm state.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

4 files changed, 8 insertions, 3 deletions

diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
index fdfba235f9f1..b49eab89c9fd 100644
--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h
@@ -278,6 +278,7 @@ enum
         LINUX_MIB_XFRMOUTPOLDEAD,               /* XfrmOutPolDead */
         LINUX_MIB_XFRMOUTPOLERROR,              /* XfrmOutPolError */
         LINUX_MIB_XFRMFWDHDRERROR,              /* XfrmFwdHdrError*/
+        LINUX_MIB_XFRMOUTSTATEINVALID,          /* XfrmOutStateInvalid */
         __LINUX_MIB_XFRMMAX
 };
 
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 95a338c89f99..3670526e70b9 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -61,6 +61,12 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
                 }
 
                 spin_lock_bh(&x->lock);
+
+                if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+                        XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEINVALID);
+                        goto error_nolock;
+                }
+
                 err = xfrm_state_check_expire(x);
                 if (err) {
                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEEXPIRED);
diff --git a/net/xfrm/xfrm_proc.c b/net/xfrm/xfrm_proc.c
index d0a1af8ed584..603903853e89 100644
--- a/net/xfrm/xfrm_proc.c
+++ b/net/xfrm/xfrm_proc.c
@@ -43,6 +43,7 @@ static const struct snmp_mib xfrm_mib_list[] = {
         SNMP_MIB_ITEM("XfrmOutPolDead", LINUX_MIB_XFRMOUTPOLDEAD),
         SNMP_MIB_ITEM("XfrmOutPolError", LINUX_MIB_XFRMOUTPOLERROR),
         SNMP_MIB_ITEM("XfrmFwdHdrError", LINUX_MIB_XFRMFWDHDRERROR),
+        SNMP_MIB_ITEM("XfrmOutStateInvalid", LINUX_MIB_XFRMOUTSTATEINVALID),
         SNMP_MIB_SENTINEL
 };
 
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 3459692092ec..05db2362a231 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1370,9 +1370,6 @@ int xfrm_state_check_expire(struct xfrm_state *x)
         if (!x->curlft.use_time)
                 x->curlft.use_time = get_seconds();
 
-        if (x->km.state != XFRM_STATE_VALID)
-                return -EINVAL;
-
         if (x->curlft.bytes >= x->lft.hard_byte_limit ||
             x->curlft.packets >= x->lft.hard_packet_limit) {
                 x->km.state = XFRM_STATE_EXPIRED;