Fix SetConfig/Login lock order inversion in the daemon

SECURITY.md

@@ -1,70 +1,12 @@
 # Security Policy
 
-NetBird's goal is to provide a secure network. The client runs as a privileged service on every machine it is installed on,
-so we take reports about it seriously and we publish what we fix.
+NetBird's goal is to provide a secure network. If you find a vulnerability or bug, please report it by opening an issue [here](https://github.com/netbirdio/netbird/issues/new?assignees=&labels=&template=bug-issue-report.md&title=) or by contacting us by email.
+
+There has yet to be an official bug bounty program for the NetBird project.
+
+## Supported Versions
+- We currently support only the latest version
 
 ## Reporting a Vulnerability
 
-**Please do not open a public issue for a security vulnerability.** Public issues are visible to everyone, including before
-a fix is available.
-
-Report security issues one of these two ways:
-
-- **GitHub private vulnerability reporting** — [open a private report](https://github.com/netbirdio/netbird/security/advisories/new)
-  on this repository. This is the preferred route: it keeps the discussion, the draft advisory, and the credit in one place.
-- **Email** — `security@netbird.io`.
-
-If the finding affects NetBird Cloud or our hosted infrastructure rather than the open-source code, email us rather than
-filing a repository report.
-
-### What to include
-
-A report is easier to act on when it contains:
-
-- The affected component (client, management, signal, relay, dashboard) and the version or commit you tested
-- The platform and configuration, where relevant — operating system, self-hosted or NetBird Cloud, container or host install
-- What an attacker needs before they can exploit it: network position, an account, local access, a specific privilege level
-- Steps to reproduce, and a proof of concept if you have one
-- The impact you believe it has
-
-Partial reports are still welcome. If you are unsure whether something is a security issue, send it to `security@netbird.io`
-and let us make that call.
-
-## What to expect from us
-
-- **We acknowledge your report** and tell you whether we can reproduce it.
-- **We work with you on severity and scope.** If we assess it differently than you do, we will explain why rather than
-  silently downgrade it.
-- **We fix and release**, then publish a [GitHub Security Advisory](https://github.com/netbirdio/netbird/security/advisories)
-  naming the affected version range and the patched version.
-- **We credit reporters who want to be credited.** Tell us the name or handle you would like used, or that you would rather
-  stay anonymous.
-- **We keep you in the loop** until the advisory is published.
-
-We ask that you give us a reasonable opportunity to ship a fix before disclosing the issue publicly, and that you avoid
-accessing, modifying, or exfiltrating data belonging to other people while testing. Testing against your own installation
-or your own account is always fine.
-
-## Supported Versions
-
-We support the latest release. Security fixes ship in the next version rather than as backports to older releases, so
-upgrading to the current release is how you get them.
-
-Release notifications are available by watching [releases](https://github.com/netbirdio/netbird/releases).
-
-## Published advisories
-
-Every vulnerability we fix is published as a GitHub Security Advisory on the
-[advisories page](https://github.com/netbirdio/netbird/security/advisories), including the affected version range, the
-patched version, and the reporter's credit. Advisories for the Go module are also distributed through the Go vulnerability
-database, so `govulncheck` will report them against your dependencies.
-
-## Bug bounty
-
-There is no official bug bounty program for the NetBird project. We credit reporters in advisories, and we are grateful for
-the work, but we cannot currently offer payment for reports.
-
-## Non-security bugs
-
-For bugs that are not security issues, please use the
-[issue tracker](https://github.com/netbirdio/netbird/discussions/new/choose).
+Please report security issues to `security@netbird.io`

client/server/lock_order_test.go

@@ -0,0 +1,51 @@
+package server
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/proto"
+)
+
+// The daemon takes guardedConfigMu before s.mutex. authorizeAndPrepareLogin
+// takes s.mutex while holding guardedConfigMu, so a SetConfig that grabbed
+// s.mutex first and then waited for guardedConfigMu would deadlock the daemon
+// against a concurrent login: two unprivileged IPC calls are enough.
+//
+// The held guardedConfigMu below stands in for that login. While SetConfig waits
+// for it, s.mutex must stay free, otherwise the login waiting for s.mutex could
+// never release guardedConfigMu.
+func TestSetConfig_TakesGuardedConfigMuBeforeServerMutex(t *testing.T) {
+	s, ctx, profName, username, _ := setupServerWithProfile(t)
+
+	s.guardedConfigMu.Lock()
+
+	done := make(chan error, 1)
+	go func() {
+		_, err := s.SetConfig(ctx, &proto.SetConfigRequest{
+			ProfileName: profName,
+			Username:    username,
+		})
+		done <- err
+	}()
+
+	require.Never(t, func() bool {
+		if !s.mutex.TryLock() {
+			return true
+		}
+		s.mutex.Unlock()
+		return false
+	}, 500*time.Millisecond, 10*time.Millisecond,
+		"SetConfig held s.mutex while waiting for guardedConfigMu, which deadlocks against a concurrent login")
+
+	s.guardedConfigMu.Unlock()
+
+	select {
+	case err := <-done:
+		require.NoError(t, err)
+	case <-time.After(5 * time.Second):
+		t.Fatal("SetConfig did not finish after guardedConfigMu was released")
+	}
+}

client/server/server.go

@@ -393,6 +393,16 @@ func (s *Server) loginAttempt(ctx context.Context, setupKey, jwtToken string) (i
 
 // Login uses setup key to prepare configuration for the daemon.
 func (s *Server) SetConfig(callerCtx context.Context, msg *proto.SetConfigRequest) (*proto.SetConfigResponse, error) {
+	// Privilege gate: refuse the parts of the request that would let a local
+	// user turn the root daemon into a root shell. Held across the write so the
+	// config cannot gain the SSH server between the decision and the update.
+	//
+	// Taken before s.mutex: authorizeAndPrepareLogin takes s.mutex while holding
+	// guardedConfigMu, so acquiring the two in the other order here would let a
+	// concurrent login deadlock the daemon.
+	s.guardedConfigMu.Lock()
+	defer s.guardedConfigMu.Unlock()
+
 	s.mutex.Lock()
 	defer s.mutex.Unlock()
 
@@ -417,12 +427,6 @@ func (s *Server) SetConfig(callerCtx context.Context, msg *proto.SetConfigReques
 		return nil, err
 	}
 
-	// Privilege gate: refuse the parts of the request that would let a local
-	// user turn the root daemon into a root shell. Held across the write so the
-	// config cannot gain the SSH server between the decision and the update.
-	s.guardedConfigMu.Lock()
-	defer s.guardedConfigMu.Unlock()
-
 	stored, err := s.storedProfileConfig(msg.ProfileName, msg.Username)
 	if err != nil {
 		return nil, err

client/ui/netbird-ui.rb.tmpl

@@ -29,13 +29,8 @@ cask "{{ $projectName }}" do
   end
 
   uninstall_preflight do
-    system_command "/bin/sh",
-                   args: ["-c", <<~CMD],
-                     launchctl bootout system/netbird 2>/dev/null || \
-                       launchctl unload /Library/LaunchDaemons/netbird.plist 2>/dev/null || true
-                     rm -f /Library/LaunchDaemons/netbird.plist
-                   CMD
-                   sudo: true
+    system_command "#{appdir}/Netbird UI.app/uninstaller.sh",
+                   sudo: false
   end
 
   name "Netbird UI"