LU-17317 gss: do not continue using expired reverse context

[fs/lustre-release.git] / lustre / ptlrpc / gss / gss_keyring.c

diff --git a/lustre/ptlrpc/gss/gss_keyring.c b/lustre/ptlrpc/gss/gss_keyring.c
index 5dfb73f..041b06f 100644 (file)
--- a/lustre/ptlrpc/gss/gss_keyring.c
+++ b/lustre/ptlrpc/gss/gss_keyring.c
@@ -480,26 +480,32 @@ struct ptlrpc_cli_ctx * sec_lookup_root_ctx_kr(struct ptlrpc_sec *sec)
 {
        struct gss_sec_keyring  *gsec_kr = sec2gsec_keyring(sec);
        struct ptlrpc_cli_ctx   *ctx = NULL;
+       time64_t now = ktime_get_real_seconds();
 
        spin_lock(&sec->ps_lock);
 
-        ctx = gsec_kr->gsk_root_ctx;
+       ctx = gsec_kr->gsk_root_ctx;
 
-        if (ctx == NULL && unlikely(sec_is_reverse(sec))) {
+       if (ctx == NULL && unlikely(sec_is_reverse(sec))) {
                struct ptlrpc_cli_ctx   *tmp;
 
-                /* reverse ctx, search root ctx in list, choose the one
-                 * with shortest expire time, which is most possibly have
-                 * an established peer ctx at client side. */
+               /* For reverse context, browse list and pick the one with
+                * shortest expire time and that has not expired yet.
+                * This one is most likely to have an established peer context
+                * on client side.
+                */
                hlist_for_each_entry(tmp, &gsec_kr->gsk_clist, cc_cache) {
-                        if (ctx == NULL || ctx->cc_expire == 0 ||
-                            ctx->cc_expire > tmp->cc_expire) {
-                                ctx = tmp;
-                                /* promote to be root_ctx */
-                                gsec_kr->gsk_root_ctx = ctx;
-                        }
-                }
-        }
+                       if (ctx == NULL || ctx->cc_expire == 0 ||
+                           (tmp->cc_expire > now &&
+                            tmp->cc_expire < ctx->cc_expire) ||
+                           (ctx->cc_expire < now &&
+                            tmp->cc_expire > ctx->cc_expire)) {
+                               ctx = tmp;
+                               /* promote to be root_ctx */
+                               gsec_kr->gsk_root_ctx = ctx;
+                       }
+               }
+       }
 
        if (ctx) {
                LASSERT(atomic_read(&ctx->cc_refcount) > 0);