From 6500ce6442ad9d48bdb36734aa1b7725e3c23902 Mon Sep 17 00:00:00 2001
From: Thiago Kenji Okada <thiagokokada@gmail.com>
Date: Mon, 28 Sep 2026 10:57:35 +0100
Subject: [PATCH] nixos-version: escape specialisations and use
 kernel.modDirVersion if available

---
 nixos/modules/installer/tools/nixos-version.sh |  8 ++++----
 nixos/modules/installer/tools/tools.nix        | 12 +++++++++---
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/nixos/modules/installer/tools/nixos-version.sh b/nixos/modules/installer/tools/nixos-version.sh
index c9ca4a634d82..a2aa76db9cd2 100644
--- a/nixos/modules/installer/tools/nixos-version.sh
+++ b/nixos/modules/installer/tools/nixos-version.sh
@@ -28,15 +28,15 @@ case "$1" in
     echo "@kernelVersion@"
     ;;
   --specialisations)
-    if [[ -z "@specialisations@" ]]; then
+    specialisations=@specialisations@
+    if [[ -z "$specialisations" ]]; then
       echo "$0: no specialisations found" >&2
       exit 1
-    else
-      echo "@specialisations@"
     fi
+    printf '%s\n' "$specialisations"
     ;;
   --json)
-    cat <<EOF
+    cat <<'EOF'
 @json@
 EOF
     ;;
diff --git a/nixos/modules/installer/tools/tools.nix b/nixos/modules/installer/tools/tools.nix
index 7757a8b4e836..eedbc8147ce3 100644
--- a/nixos/modules/installer/tools/tools.nix
+++ b/nixos/modules/installer/tools/tools.nix
@@ -58,13 +58,19 @@ let
       inherit (config.system.nixos) version codeName revision;
       inherit (config.system) configurationRevision;
       kernelVersion =
-        if config.boot.kernel.enable then config.boot.kernelPackages.kernel.version else null;
-      specialisations = lib.attrNames config.specialisation;
+        if config.boot.kernel.enable then
+          # modDirVersion returns 6.18.54-xanmod1 instead of 6.18.54
+          config.boot.kernelPackages.kernel.modDirVersion or config.boot.kernelPackages.kernel.version
+        else
+          null;
+      specialisations = lib.escapeShellArg (
+        lib.concatStringsSep " " (lib.attrNames config.specialisation)
+      );
 
       json = builtins.toJSON (
         {
           nixosVersion = config.system.nixos.version;
-          inherit kernelVersion specialisations;
+          specialisations = lib.attrNames config.specialisation;
         }
         // lib.optionalAttrs (kernelVersion != null) {
           inherit kernelVersion;