From 5b3c6814a99cb02d6c689b21518591e01c47539b Mon Sep 17 00:00:00 2001
From: Mathias Fredriksson <mafredri@gmail.com>
Date: Mon, 26 Jun 2023 17:09:24 +0000
Subject: [PATCH] fix(enterprise/coderd): avoid deadlock during entitlements
 update

---
 enterprise/coderd/coderd.go          | 11 +++++++----
 enterprise/coderd/workspaceagents.go |  4 ++--
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/enterprise/coderd/coderd.go b/enterprise/coderd/coderd.go
index 6545e599202f3..4a03731c5b21a 100644
--- a/enterprise/coderd/coderd.go
+++ b/enterprise/coderd/coderd.go
@@ -313,8 +313,9 @@ type API struct {
 	// ProxyHealth checks the reachability of all workspace proxies.
 	ProxyHealth *proxyhealth.ProxyHealth
 
-	entitlementsMu sync.RWMutex
-	entitlements   codersdk.Entitlements
+	entitlementsUpdateMu sync.Mutex
+	entitlementsMu       sync.RWMutex
+	entitlements         codersdk.Entitlements
 }
 
 func (api *API) Close() error {
@@ -329,8 +330,8 @@ func (api *API) Close() error {
 }
 
 func (api *API) updateEntitlements(ctx context.Context) error {
-	api.entitlementsMu.Lock()
-	defer api.entitlementsMu.Unlock()
+	api.entitlementsUpdateMu.Lock()
+	defer api.entitlementsUpdateMu.Unlock()
 
 	entitlements, err := license.Entitlements(
 		ctx, api.Database,
@@ -457,6 +458,8 @@ func (api *API) updateEntitlements(ctx context.Context) error {
 		}
 	}
 
+	api.entitlementsMu.Lock()
+	defer api.entitlementsMu.Unlock()
 	api.entitlements = entitlements
 	api.AGPL.SiteHandler.Entitlements.Store(&entitlements)
 
diff --git a/enterprise/coderd/workspaceagents.go b/enterprise/coderd/workspaceagents.go
index d5595e6570543..05590342aec5b 100644
--- a/enterprise/coderd/workspaceagents.go
+++ b/enterprise/coderd/workspaceagents.go
@@ -9,9 +9,9 @@ import (
 )
 
 func (api *API) shouldBlockNonBrowserConnections(rw http.ResponseWriter) bool {
-	api.entitlementsMu.Lock()
+	api.entitlementsMu.RLock()
 	browserOnly := api.entitlements.Features[codersdk.FeatureBrowserOnly].Enabled
-	api.entitlementsMu.Unlock()
+	api.entitlementsMu.RUnlock()
 	if browserOnly {
 		httpapi.Write(context.Background(), rw, http.StatusConflict, codersdk.Response{
 			Message: "Non-browser connections are disabled for your deployment.",