1 files changed, 37 insertions, 26 deletions

diff --git a/nixpkgs/nixos/modules/services/networking/nbd.nix b/nixpkgs/nixos/modules/services/networking/nbd.nix
index 87f8c41a8e5c..76ca11dfea76 100644
--- a/nixpkgs/nixos/modules/services/networking/nbd.nix
+++ b/nixpkgs/nixos/modules/services/networking/nbd.nix
@@ -4,28 +4,34 @@ with lib;
 
 let
   cfg = config.services.nbd;
-  configFormat = pkgs.formats.ini { };
   iniFields = with types; attrsOf (oneOf [ bool int float str ]);
-  serverConfig = configFormat.generate "nbd-server-config"
-    ({
-      generic =
-        (cfg.server.extraOptions // {
-          user = "root";
-          group = "root";
-          port = cfg.server.listenPort;
-        } // (optionalAttrs (cfg.server.listenAddress != null) {
-          listenaddr = cfg.server.listenAddress;
-        }));
-    }
-    // (mapAttrs
+  # The `[generic]` section must come before all the others in the
+  # config file.  This means we can't just dump an attrset to INI
+  # because that sorts the sections by name.  Instead, we serialize it
+  # on its own first.
+  genericSection = {
+    generic = (cfg.server.extraOptions // {
+      user = "root";
+      group = "root";
+      port = cfg.server.listenPort;
+    } // (optionalAttrs (cfg.server.listenAddress != null) {
+      listenaddr = cfg.server.listenAddress;
+    }));
+  };
+  exportSections =
+    mapAttrs
       (_: { path, allowAddresses, extraOptions }:
         extraOptions // {
           exportname = path;
         } // (optionalAttrs (allowAddresses != null) {
           authfile = pkgs.writeText "authfile" (concatStringsSep "\n" allowAddresses);
         }))
-      cfg.server.exports)
-    );
+      cfg.server.exports;
+  serverConfig =
+    pkgs.writeText "nbd-server-config" ''
+      ${lib.generators.toINI {} genericSection}
+      ${lib.generators.toINI {} exportSections}
+    '';
   splitLists =
     partition
       (path: hasPrefix "/dev/" path)
@@ -42,7 +48,7 @@ in
         listenPort = mkOption {
           type = types.port;
           default = 10809;
-          description = "Port to listen on. The port is NOT automatically opened in the firewall.";
+          description = lib.mdDoc "Port to listen on. The port is NOT automatically opened in the firewall.";
         };
 
         extraOptions = mkOption {
@@ -50,22 +56,21 @@ in
           default = {
             allowlist = false;
           };
-          description = ''
+          description = lib.mdDoc ''
             Extra options for the server. See
-            <citerefentry><refentrytitle>nbd-server</refentrytitle>
-            <manvolnum>5</manvolnum></citerefentry>.
+            {manpage}`nbd-server(5)`.
           '';
         };
 
         exports = mkOption {
-          description = "Files or block devices to make available over the network.";
+          description = lib.mdDoc "Files or block devices to make available over the network.";
           default = { };
           type = with types; attrsOf
             (submodule {
               options = {
                 path = mkOption {
                   type = str;
-                  description = "File or block device to export.";
+                  description = lib.mdDoc "File or block device to export.";
                   example = "/dev/sdb1";
                 };
 
@@ -73,7 +78,7 @@ in
                   type = nullOr (listOf str);
                   default = null;
                   example = [ "10.10.0.0/24" "127.0.0.1" ];
-                  description = "IPs and subnets that are authorized to connect for this device. If not specified, the server will allow all connections.";
+                  description = lib.mdDoc "IPs and subnets that are authorized to connect for this device. If not specified, the server will allow all connections.";
                 };
 
                 extraOptions = mkOption {
@@ -82,10 +87,9 @@ in
                     flush = true;
                     fua = true;
                   };
-                  description = ''
+                  description = lib.mdDoc ''
                     Extra options for this export. See
-                    <citerefentry><refentrytitle>nbd-server</refentrytitle>
-                    <manvolnum>5</manvolnum></citerefentry>.
+                    {manpage}`nbd-server(5)`.
                   '';
                 };
               };
@@ -94,7 +98,7 @@ in
 
         listenAddress = mkOption {
           type = with types; nullOr str;
-          description = "Address to listen on. If not specified, the server will listen on all interfaces.";
+          description = lib.mdDoc "Address to listen on. If not specified, the server will listen on all interfaces.";
           default = null;
           example = "10.10.0.1";
         };
@@ -103,6 +107,13 @@ in
   };
 
   config = mkIf cfg.server.enable {
+    assertions = [
+      {
+        assertion = !(cfg.server.exports ? "generic");
+        message = "services.nbd.server exports must not be named 'generic'";
+      }
+    ];
+
     boot.kernelModules = [ "nbd" ];
 
     systemd.services.nbd-server = {