glusterd: perform rcu_read_lock/unlock() under cleanup_lock mutex

Problem: glusterd should not try to acquire locks on any resources,
when it already received a SIGTERM and cleanup is started. Otherwise
we might hit segfault, since the thread which is going through
cleanup path will be freeing up the resouces and some other thread
might be trying to acquire locks on freed resources.

Solution: perform rcu_read_lock/unlock() under cleanup_lock mutex.

fixes: bz#1654270
Change-Id: I87a97cfe4f272f74f246d688660934638911ce54
Signed-off-by: Sanju Rakonde <srakonde@redhat.com>

1 files changed, 37 insertions, 37 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-handler.c b/xlators/mgmt/glusterd/src/glusterd-handler.c
index ef1df3c3788..db58b3af8cf 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handler.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handler.c
@@ -103,7 +103,7 @@ glusterd_handle_friend_req(rpcsvc_request_t *req, uuid_t uuid, char *hostname,
 
     ret = glusterd_remote_hostname_get(req, rhost, sizeof(rhost));
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
 
     peerinfo = glusterd_peerinfo_find(uuid, rhost);
 
@@ -174,7 +174,7 @@ glusterd_handle_friend_req(rpcsvc_request_t *req, uuid_t uuid, char *hostname,
         ret = GLUSTERD_CONNECTION_AWAITED;
 
 out:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
 
     if (ret && (ret != GLUSTERD_CONNECTION_AWAITED)) {
         if (ctx && ctx->hostname)
@@ -207,7 +207,7 @@ glusterd_handle_unfriend_req(rpcsvc_request_t *req, uuid_t uuid, char *hostname,
     if (!port)
         port = GF_DEFAULT_BASE_PORT;
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
 
     peerinfo = glusterd_peerinfo_find(uuid, hostname);
 
@@ -261,7 +261,7 @@ glusterd_handle_unfriend_req(rpcsvc_request_t *req, uuid_t uuid, char *hostname,
     ret = 0;
 
 out:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
 
     if (0 != ret) {
         if (ctx && ctx->hostname)
@@ -904,9 +904,9 @@ __glusterd_handle_cluster_lock(rpcsvc_request_t *req)
     gf_msg_debug(this->name, 0, "Received LOCK from uuid: %s",
                  uuid_utoa(lock_req.uuid));
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     ret = (glusterd_peerinfo_find_by_uuid(lock_req.uuid) == NULL);
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     if (ret) {
         gf_msg(this->name, GF_LOG_WARNING, 0, GD_MSG_PEER_NOT_FOUND,
                "%s doesn't "
@@ -1063,9 +1063,9 @@ __glusterd_handle_stage_op(rpcsvc_request_t *req)
     ret = dict_get_bin(req_ctx->dict, "transaction_id", (void **)&txn_id);
     gf_msg_debug(this->name, 0, "transaction ID = %s", uuid_utoa(*txn_id));
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     ret = (glusterd_peerinfo_find_by_uuid(op_req.uuid) == NULL);
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     if (ret) {
         gf_msg(this->name, GF_LOG_WARNING, 0, GD_MSG_PEER_NOT_FOUND,
                "%s doesn't "
@@ -1144,9 +1144,9 @@ __glusterd_handle_commit_op(rpcsvc_request_t *req)
         goto out;
     }
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     ret = (glusterd_peerinfo_find_by_uuid(op_req.uuid) == NULL);
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     if (ret) {
         gf_msg(this->name, GF_LOG_WARNING, 0, GD_MSG_PEER_NOT_FOUND,
                "%s doesn't "
@@ -1267,12 +1267,12 @@ __glusterd_handle_cli_probe(rpcsvc_request_t *req)
         goto out;
     }
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
 
     peerinfo = glusterd_peerinfo_find_by_hostname(hostname);
     ret = (peerinfo && gd_peer_has_address(peerinfo, hostname));
 
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
 
     if (ret) {
         gf_msg_debug("glusterd", 0,
@@ -2286,7 +2286,7 @@ __glusterd_handle_fsm_log(rpcsvc_request_t *req)
         conf = this->private;
         ret = glusterd_sm_tr_log_add_to_dict(dict, &conf->op_sm_log);
     } else {
-        rcu_read_lock();
+        RCU_READ_LOCK;
 
         peerinfo = glusterd_peerinfo_find_by_hostname(cli_req.name);
         if (!peerinfo) {
@@ -2296,7 +2296,7 @@ __glusterd_handle_fsm_log(rpcsvc_request_t *req)
             ret = glusterd_sm_tr_log_add_to_dict(dict, &peerinfo->sm_log);
         }
 
-        rcu_read_unlock();
+        RCU_READ_UNLOCK;
     }
 
 out:
@@ -2440,9 +2440,9 @@ __glusterd_handle_cluster_unlock(rpcsvc_request_t *req)
     gf_msg_debug(this->name, 0, "Received UNLOCK from uuid: %s",
                  uuid_utoa(unlock_req.uuid));
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     ret = (glusterd_peerinfo_find_by_uuid(unlock_req.uuid) == NULL);
-    rcu_read_unlock();
+    RCU_READ_LOCK;
     if (ret) {
         gf_msg(this->name, GF_LOG_WARNING, 0, GD_MSG_PEER_NOT_FOUND,
                "%s doesn't "
@@ -2753,11 +2753,11 @@ __glusterd_handle_friend_update(rpcsvc_request_t *req)
     }
 
     ret = 0;
-    rcu_read_lock();
+    RCU_READ_LOCK;
     if (glusterd_peerinfo_find(friend_req.uuid, NULL) == NULL) {
         ret = -1;
     }
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     if (ret) {
         gf_msg(this->name, GF_LOG_CRITICAL, 0, GD_MSG_REQ_FROM_UNKNOWN_PEER,
                "Received friend update request "
@@ -2816,7 +2816,7 @@ __glusterd_handle_friend_update(rpcsvc_request_t *req)
 
         snprintf(key, sizeof(key), "friend%d", i);
 
-        rcu_read_lock();
+        RCU_READ_LOCK;
         peerinfo = glusterd_peerinfo_find(uuid, NULL);
         if (peerinfo == NULL) {
             /* Create a new peer and add it to the list as there is
@@ -2861,7 +2861,7 @@ __glusterd_handle_friend_update(rpcsvc_request_t *req)
             }
         }
     unlock:
-        rcu_read_unlock();
+        RCU_READ_UNLOCK;
         if (ret)
             break;
 
@@ -2964,7 +2964,7 @@ __glusterd_handle_probe_query(rpcsvc_request_t *req)
         goto out;
     }
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     peerinfo = glusterd_peerinfo_find(probe_req.uuid, remote_hostname);
     if ((peerinfo == NULL) && (!cds_list_empty(&conf->peers))) {
         rsp.op_ret = -1;
@@ -2984,7 +2984,7 @@ __glusterd_handle_probe_query(rpcsvc_request_t *req)
             rsp.op_errno = GF_PROBE_ADD_FAILED;
         }
     }
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
 
 respond:
     gf_uuid_copy(rsp.uuid, MY_UUID);
@@ -3334,11 +3334,11 @@ glusterd_friend_remove(uuid_t uuid, char *hostname)
     int ret = -1;
     glusterd_peerinfo_t *peerinfo = NULL;
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
 
     peerinfo = glusterd_peerinfo_find(uuid, hostname);
     if (peerinfo == NULL) {
-        rcu_read_unlock();
+        RCU_READ_UNLOCK;
         goto out;
     }
 
@@ -3346,7 +3346,7 @@ glusterd_friend_remove(uuid_t uuid, char *hostname)
     if (ret)
         gf_msg(THIS->name, GF_LOG_WARNING, 0, GD_MSG_VOL_CLEANUP_FAIL,
                "Volumes cleanup failed");
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     /* Giving up the critical section here as glusterd_peerinfo_cleanup must
      * be called from outside a critical section
      */
@@ -3657,7 +3657,7 @@ glusterd_probe_begin(rpcsvc_request_t *req, const char *hoststr, int port,
 
     GF_ASSERT(hoststr);
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     peerinfo = glusterd_peerinfo_find(NULL, hoststr);
 
     if (peerinfo == NULL) {
@@ -3702,7 +3702,7 @@ glusterd_probe_begin(rpcsvc_request_t *req, const char *hoststr, int port,
     }
 
 out:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     gf_msg_debug("glusterd", 0, "returning %d", ret);
     return ret;
 }
@@ -3719,7 +3719,7 @@ glusterd_deprobe_begin(rpcsvc_request_t *req, const char *hoststr, int port,
     GF_ASSERT(hoststr);
     GF_ASSERT(req);
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
 
     peerinfo = glusterd_peerinfo_find(uuid, hoststr);
     if (peerinfo == NULL) {
@@ -3780,7 +3780,7 @@ glusterd_deprobe_begin(rpcsvc_request_t *req, const char *hoststr, int port,
     peerinfo->detaching = _gf_true;
 
 out:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     return ret;
 }
 
@@ -4145,7 +4145,7 @@ glusterd_list_friends(rpcsvc_request_t *req, dict_t *dict, int32_t flags)
 
     /* Reset ret to 0, needed to prevent failure in case no peers exist */
     ret = 0;
-    rcu_read_lock();
+    RCU_READ_LOCK;
     if (!cds_list_empty(&priv->peers)) {
         cds_list_for_each_entry_rcu(entry, &priv->peers, uuid_list)
         {
@@ -4156,7 +4156,7 @@ glusterd_list_friends(rpcsvc_request_t *req, dict_t *dict, int32_t flags)
         }
     }
 unlock:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     if (ret)
         goto out;
 
@@ -5609,7 +5609,7 @@ glusterd_get_state(rpcsvc_request_t *req, dict_t *dict)
     if (priv->opts)
         dict_foreach(priv->opts, glusterd_print_global_options, fp);
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     fprintf(fp, "\n[Peers]\n");
 
     cds_list_for_each_entry_rcu(peerinfo, &priv->peers, uuid_list)
@@ -5639,7 +5639,7 @@ glusterd_get_state(rpcsvc_request_t *req, dict_t *dict)
         count_bkp = 0;
         fprintf(fp, "\n");
     }
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
 
     count = 0;
     fprintf(fp, "\n[Volumes]\n");
@@ -6253,7 +6253,7 @@ glusterd_friend_remove_notify(glusterd_peerctx_t *peerctx, int32_t op_errno)
 
     GF_ASSERT(peerctx);
 
-    rcu_read_lock();
+    RCU_READ_LOCK;
     peerinfo = glusterd_peerinfo_find_by_generation(peerctx->peerinfo_gen);
     if (!peerinfo) {
         gf_msg_debug(THIS->name, 0,
@@ -6293,7 +6293,7 @@ glusterd_friend_remove_notify(glusterd_peerctx_t *peerctx, int32_t op_errno)
     }
 
 out:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
     return ret;
 }
 
@@ -6340,7 +6340,7 @@ __glusterd_peer_rpc_notify(struct rpc_clnt *rpc, void *mydata,
                event, peerctx->peername);
         return 0;
     }
-    rcu_read_lock();
+    RCU_READ_LOCK;
 
     peerinfo = glusterd_peerinfo_find_by_generation(peerctx->peerinfo_gen);
     if (!peerinfo) {
@@ -6453,7 +6453,7 @@ __glusterd_peer_rpc_notify(struct rpc_clnt *rpc, void *mydata,
     }
 
 out:
-    rcu_read_unlock();
+    RCU_READ_UNLOCK;
 
     glusterd_friend_sm();
     glusterd_op_sm();