LU-14655 lnet: Protect lpni deref in lnet_health_check

[fs/lustre-release.git] / lnet / lnet / lib-msg.c

diff --git a/lnet/lnet/lib-msg.c b/lnet/lnet/lib-msg.c
index 7dab8d5..f23d7d3 100644 (file)
--- a/lnet/lnet/lib-msg.c
+++ b/lnet/lnet/lib-msg.c
@@ -824,35 +824,6 @@ lnet_health_check(struct lnet_msg *msg)
                attempt_local_resend = attempt_remote_resend = false;
        }
 
-       /* Don't further decrement the health value if a recovery message
-        * failed.
-        */
-       if (msg->msg_recovery)
-               handle_local_health = handle_remote_health = false;
-       else
-               handle_local_health = handle_remote_health = true;
-
-       /* For local failures, health/recovery/resends are not needed if I only
-        * have a single (non-lolnd) interface. NB: pb_nnis includes the lolnd
-        * interface, so a single-rail node would have pb_nnis == 2.
-        */
-       if (the_lnet.ln_ping_target->pb_nnis <= 2) {
-               handle_local_health = false;
-               attempt_local_resend = false;
-       }
-
-       /* For remote failures, health/recovery/resends are not needed if the
-        * peer only has a single interface. Special case for routers where we
-        * rely on health feature to manage route aliveness. NB: unlike pb_nnis
-        * above, lp_nnis does _not_ include the lolnd, so a single-rail node
-        * would have lp_nnis == 1.
-        */
-       if (lpni && lpni->lpni_peer_net->lpn_peer->lp_nnis <= 1) {
-               attempt_remote_resend = false;
-               if (!lnet_isrouter(lpni))
-                       handle_remote_health = false;
-       }
-
        if (!lo)
                LASSERT(ni && lpni);
        else
@@ -866,11 +837,45 @@ lnet_health_check(struct lnet_msg *msg)
 
        /*
         * stats are only incremented for errors so avoid wasting time
-        * incrementing statistics if there is no error.
+        * incrementing statistics if there is no error. Similarly, whether to
+        * update health values or perform resends is only applicable for
+        * messages with a health status != OK.
         */
        if (hstatus != LNET_MSG_STATUS_OK) {
+               /* Don't further decrement the health value if a recovery
+                * message failed.
+                */
+               if (msg->msg_recovery)
+                       handle_local_health = handle_remote_health = false;
+               else
+                       handle_local_health = handle_remote_health = true;
+
+               /* For local failures, health/recovery/resends are not needed if
+                * I only have a single (non-lolnd) interface. NB: pb_nnis
+                * includes the lolnd interface, so a single-rail node would
+                * have pb_nnis == 2.
+                */
+               if (the_lnet.ln_ping_target->pb_nnis <= 2) {
+                       handle_local_health = false;
+                       attempt_local_resend = false;
+               }
+
                lnet_net_lock(0);
                lnet_incr_hstats(ni, lpni, hstatus);
+               /* For remote failures, health/recovery/resends are not needed
+                * if the peer only has a single interface. Special case for
+                * routers where we rely on health feature to manage route
+                * aliveness. NB: unlike pb_nnis above, lp_nnis does _not_
+                * include the lolnd, so a single-rail node would have
+                * lp_nnis == 1.
+                */
+               if (lpni && lpni->lpni_peer_net &&
+                   lpni->lpni_peer_net->lpn_peer &&
+                   lpni->lpni_peer_net->lpn_peer->lp_nnis <= 1) {
+                       attempt_remote_resend = false;
+                       if (!lnet_isrouter(lpni))
+                               handle_remote_health = false;
+               }
                lnet_net_unlock(0);
        }