fix: audit LOW fixes — dead uid, home_dir warn, clippy sweep, debug value (v0.8.5)

- users::User: drop the unused `uid` field and its getuid() assignment.
  The compiler dead_code warning is gone, and the synthetic `u32::MAX`
  sentinel in the panel fallback is obsolete too.
- panel: surface a log::warn! when dirs::home_dir() returns None instead
  of silently falling back to an empty PathBuf that would make avatars
  look for .face in the current working directory.
- Apply three clippy suggestions: two collapsible if-let + && chains in
  users::get_avatar_path_with and config::resolve_background_path_with,
  and a redundant closure in panel::execute_action's spawn_blocking.
- main: require MOONSET_DEBUG=1 to escalate log verbosity — mere
  presence of the var must not dump path info into the journal.

.gitea/workflows/update-pkgver.yaml

@@ -0,0 +1,43 @@
+# ABOUTME: Updates pkgver in moonarch-pkgbuilds after a push to main.
+# ABOUTME: Ensures paru detects new versions of this package.
+
+name: Update PKGBUILD version
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  update-pkgver:
+    runs-on: moonarch
+    steps:
+      - name: Checkout source repo
+        run: |
+          git clone --bare http://gitea:3000/nevaforget/moonset.git source.git
+          cd source.git
+          PKGVER=$(git describe --long --tags | sed 's/^v//;s/-/.r/;s/-/./')
+          echo "New pkgver: $PKGVER"
+          echo "$PKGVER" > /tmp/pkgver
+
+      - name: Update PKGBUILD
+        run: |
+          PKGVER=$(cat /tmp/pkgver)
+          git clone http://gitea:3000/nevaforget/moonarch-pkgbuilds.git pkgbuilds
+          cd pkgbuilds
+
+          OLD_VER=$(grep '^pkgver=' moonset-git/PKGBUILD | cut -d= -f2)
+          if [ "$OLD_VER" = "$PKGVER" ]; then
+            echo "pkgver already up to date ($PKGVER)"
+            exit 0
+          fi
+
+          sed -i "s/^pkgver=.*/pkgver=$PKGVER/" moonset-git/PKGBUILD
+          sed -i "s/^\tpkgver = .*/\tpkgver = $PKGVER/" moonset-git/.SRCINFO
+          echo "Updated pkgver: $OLD_VER → $PKGVER"
+
+          git config user.name "pkgver-bot"
+          git config user.email "gitea@moonarch.de"
+          git add moonset-git/PKGBUILD moonset-git/.SRCINFO
+          git commit -m "chore(moonset-git): bump pkgver to $PKGVER"
+          git -c http.extraHeader="Authorization: token ${{ secrets.PKGBUILD_TOKEN }}" push

CHANGELOG.md

@@ -3,6 +3,57 @@
 All notable changes to this project will be documented in this file.
 Format based on [Keep a Changelog](https://keepachangelog.com/).
 
+## [0.8.0] - 2026-03-30
+
+### Changed
+
+- Replace `canonicalize()` with `symlink_metadata` + `is_file` + `!is_symlink` for avatar lookup — prevents symlink traversal to arbitrary files
+- Replace `canonicalize()` with same symlink-safe check in `resolve_background_path`
+- Downscale wallpaper to `MAX_BLUR_DIMENSION` (1920px) before GPU blur — prevents excessive memory use on high-res images
+- Validate `background_blur` per config source — invalid user value preserves system default instead of silently falling back to 0
+
+### Fixed
+
+- Fix blur padding offset from `(0,0)` to `(-pad,-pad)` to prevent edge darkening on blurred wallpaper
+
+## [0.7.3] - 2026-03-29
+
+### Fixed
+
+- Fix shutdown and reboot — `loginctl` does not support `poweroff`/`reboot` verbs, switched to `systemctl poweroff` and `systemctl reboot`
+
+## [0.7.2] - 2026-03-29
+
+### Fixed
+
+- Fix CSS priority so app styles override GTK4 user theme (Colloid-Catppuccin) — use `STYLE_PROVIDER_PRIORITY_USER` instead of `STYLE_PROVIDER_PRIORITY_APPLICATION`
+- Replace `border-radius: 50%` with `9999px` — GTK4 CSS does not reliably support percentage-based border-radius
+
+## [0.7.1] - 2026-03-28
+
+### Fixed
+
+- Fix edge darkening on blurred wallpaper — GskBlurNode sampled transparent pixels outside texture bounds, now renders with 3x-sigma padding and crops back
+
+## [0.7.0] - 2026-03-28
+
+### Added
+
+- Blur validation: `background_blur` must be 0.0–200.0 (negative, NaN, infinite, and extreme values are rejected with a warning)
+- `detect_locale_with()` testable DI function for locale detection (4 new tests)
+- Path canonicalization for `~/.face` and AccountsService avatar paths (resolves symlinks, prevents passing arbitrary files to gdk-pixbuf)
+
+### Changed
+
+- Replace busy-loop polling (`try_wait` + `sleep(100ms)`) in `run_command` with blocking `child.wait()` + timeout thread — eliminates poll latency and thread waste
+- Move config loading from `activate()` to `main()` — filesystem I/O no longer blocks the GTK main loop
+- Click-to-dismiss now attached to overlay instead of background picture (works with or without wallpaper)
+
+### Removed
+
+- Embedded fallback wallpaper from GResource bundle — moonarch provides `/usr/share/moonarch/wallpaper.jpg` at install time, binary size dropped from ~3.2MB to ~1.3MB
+- GResource fallback path in `resolve_background_path` — returns `Option<PathBuf>` now, `None` falls through to CSS background
+
 ## [0.6.0] - 2026-03-28
 
 ### Added

CLAUDE.md

@@ -1,7 +1,5 @@
 # Moonset
 
-**Name**: Hekate (Göttin der Wegkreuzungen — passend zum Power-Menu, das den Weg der Session bestimmt)
-
 ## Projekt
 
 Moonset ist ein Wayland Session Power Menu, gebaut mit Rust + gtk4-rs + gtk4-layer-shell.
@@ -17,7 +15,7 @@ Lock, Logout, Hibernate, Reboot, Shutdown.
 ## Projektstruktur
 
 - `src/` — Rust-Quellcode (main.rs, power.rs, i18n.rs, config.rs, users.rs, panel.rs)
-- `resources/` — GResource-Assets (style.css, wallpaper.jpg komprimiert, default-avatar.svg)
+- `resources/` — GResource-Assets (style.css, default-avatar.svg)
 - `config/` — Beispiel-Konfigurationsdateien
 
 ## Kommandos
@@ -54,6 +52,6 @@ Kurzfassung der wichtigsten Entscheidungen:
 - **System-Icons**: Adwaita/Catppuccin liefern alle benötigten symbolischen Icons
 - **Lock ohne Confirmation**: Lock ist sofort reversibel, braucht kein Confirm
 - **Absolute Pfade für Binaries**: `/usr/bin/systemctl` etc. statt relativer Pfade (Security)
-- **GResource-Bundle**: CSS, Wallpaper (komprimiert) und Default-Avatar sind in die Binary kompiliert
+- **GResource-Bundle**: CSS und Default-Avatar sind in die Binary kompiliert (Wallpaper kommt vom Dateisystem)
 - **Async Power Actions**: `glib::spawn_future_local` + `gio::spawn_blocking` mit 30s Timeout
 - **Journal-Logging**: `systemd-journal-logger` statt File-Logging — `journalctl -t moonset`, Debug-Level per `MOONSET_DEBUG` Env-Var

Cargo.lock

@@ -616,7 +616,7 @@ dependencies = [
 
 [[package]]
 name = "moonset"
-version = "0.5.0"
+version = "0.8.5"
 dependencies = [
  "dirs",
  "gdk-pixbuf",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "moonset"
-version = "0.6.0"
+version = "0.8.5"
 edition = "2024"
 description = "Wayland session power menu with GTK4 and Layer Shell"
 license = "MIT"
@@ -14,7 +14,7 @@ gdk-pixbuf = "0.22"
 toml = "0.8"
 dirs = "6"
 serde = { version = "1", features = ["derive"] }
-nix = { version = "0.29", features = ["user"] }
+nix = { version = "0.29", features = ["user", "signal"] }
 graphene-rs = { version = "0.22", package = "graphene-rs" }
 log = "0.4"
 systemd-journal-logger = "2.2"
@@ -22,5 +22,10 @@ systemd-journal-logger = "2.2"
 [dev-dependencies]
 tempfile = "3"
 
+[profile.release]
+lto = "thin"
+codegen-units = 1
+strip = true
+
 [build-dependencies]
 glib-build-tools = "0.22"

DECISIONS.md

@@ -2,72 +2,107 @@
 
 Architectural and design decisions for Moonset, in reverse chronological order.
 
+## 2026-04-24 – Audit LOW fixes: dead uid field, home_dir warn, clippy sweep, debug value (v0.8.5)
+
+- **Who**: ClaudeCode, Dom
+- **Why**: Five LOW findings cleared in one pass. (1) `User::uid` was populated from `getuid()` but never read — a compiler `dead_code` warning for a field on the public API. (2) Falling back to a synthetic user when `get_current_user()` returned None used `uid: u32::MAX`, an undocumented sentinel that became moot once uid was removed. (3) `dirs::home_dir().unwrap_or_default()` silently yielded `PathBuf::new()` on failure; avatars would then look for `.face` in the current working directory. (4) `cargo clippy` flagged three suggestions (two collapsible `if`, one redundant closure) that had crept in. (5) `MOONSET_DEBUG` promoted log verbosity on mere presence, leaking path information into the journal.
+- **Tradeoffs**: Dropping `uid` from `User` is a minor API break for any internal caller expecting the field — none existed. The synthetic fallback now surfaces `log::warn!` when home resolution fails, which should be rare outside of pathological sandbox environments.
+- **How**: (1) Remove `pub uid: u32` from `User` and the `uid: uid.as_raw()` assignment in `get_current_user`. (2) Panel fallback drops the `uid` field entirely. (3) `dirs::home_dir().unwrap_or_else(|| { log::warn!(...); PathBuf::new() })`. (4) `cargo clippy --fix` for the two collapsible ifs, manual collapse of `if-let` + `&&` chain, redundant closure replaced with the function itself. (5) `MOONSET_DEBUG` now requires the literal value `"1"` to escalate to Debug.
+
+## 2026-04-24 – Audit MEDIUM fixes: timeout guard, POSIX locale, button desensitize, wallpaper allowlist (v0.8.4)
+
+- **Who**: ClaudeCode, Dom
+- **Why**: Five MEDIUM findings: (1) `run_command`'s timeout thread leaked a 30 s gio::spawn_blocking slot if `child.wait()` errored, because `done.store(true)` ran after the `?`. (2) Timeout detection compared `status.signal() == Some(9)` — a hardcoded signal number that also misclassifies OOM-killer SIGKILL as our timeout. (3) `execute_action` never desensitized the button_box, so a double-click or accidental keyboard repeat fired the action twice. (4) `detect_locale` read only `LANG`, ignoring POSIX priority order (`LC_ALL` > `LC_MESSAGES` > `LANG`) — a common dual-language setup picked the wrong UI language. (5) The wallpaper path was passed to gdk-pixbuf without extension or size restriction, widening the image-parser attack surface and allowing unbounded decode latency.
+- **Tradeoffs**: The extension allowlist (`jpg`, `jpeg`, `png`, `webp`) rejects exotic formats users might have used before. The 10 MB size cap rejects uncompressed/high-quality 4K wallpapers; acceptable for a power menu. Memory ordering on the `done` flag is now `Release`/`Acquire` instead of `Relaxed` — no runtime cost but correct across threads.
+- **How**: (1) RAII `DoneGuard` struct sets `done.store(true, Release)` in its `Drop`, so the flag fires on every function exit path. A second `timed_out` AtomicBool distinguishes our SIGKILL from an external one. (2) Replace `Some(9)` with the `timed_out` flag check. (3) `execute_action` now takes `button_box: &gtk::Box`, calls `set_sensitive(false)` on entry and re-enables it on error paths; success paths that quit skip the re-enable. All call sites updated. (4) `detect_locale` reads `LC_ALL`, `LC_MESSAGES`, `LANG` in order, picking the first non-empty value before falling back to `/etc/locale.conf`. (5) `accept_wallpaper` helper applies extension allowlist + symlink rejection + `MAX_WALLPAPER_FILE_SIZE = 10 MB`, and is called for both config-path and Moonarch fallback.
+
+## 2026-04-24 – Audit fix: avoid latent stdout pipe deadlock in run_command (v0.8.3)
+
+- **Who**: ClaudeCode, Dom
+- **Why**: Audit found that `run_command` piped the child's `stdout` but never drained it, then called blocking `child.wait()`. A child writing more than one OS pipe buffer (~64 KB on Linux) would block on `write()` while the parent blocked in `wait()` — classic pipe deadlock, broken only by the 30 s SIGKILL timeout. Current callers (`systemctl`, `niri msg`, `loginctl`) do not emit that much output, but the structure was fragile and would bite on any future command or changed behaviour.
+- **Tradeoffs**: stdout is now fully discarded. If a future caller needs stdout, it will have to drain it concurrently with `wait()` (separate reader thread).
+- **How**: Replace `.stdout(Stdio::piped())` with `.stdout(Stdio::null())` in `run_command`. `stderr` stays piped — it is drained after `wait()`, which is safe because `wait()` already reaped the child and no further writes can occur.
+
+## 2026-03-31 – Fourth audit: release profile, GResource compression, lock stderr, sync markers
+
+- **Who**: ClaudeCode, Dom
+- **Why**: Fourth triple audit found missing release profile (LTO/strip), uncompressed GResource assets, moonlock stderr suppressed (errors invisible), and duplicated code without sync markers.
+- **Tradeoffs**: moonlock stderr now inherited instead of null — errors appear in moonset's journal context. Acceptable for debugging, no security leak since moonlock logs to its own journal identifier.
+- **How**: (1) `[profile.release]` with LTO, codegen-units=1, strip. (2) `compressed="true"` on GResource entries. (3) `Stdio::inherit()` for moonlock stderr in lock(). (4) SYNC comments on duplicated blur/background functions.
+
+## 2026-03-28 – Remove wallpaper from GResource bundle
+
+- **Who**: ClaudeCode, Dom
+- **Why**: All three Moon projects (moonset, moongreet, moonlock) embedded a 374kB fallback wallpaper in the binary via GResource. Moonarch already installs `/usr/share/moonarch/wallpaper.jpg` at system setup time, making the embedded fallback unnecessary dead weight (~2MB in binary size).
+- **Tradeoffs**: If `/usr/share/moonarch/wallpaper.jpg` is missing and no user config exists, moonset shows a solid CSS background instead of a wallpaper. Acceptable — the power menu is functional without a wallpaper image.
+- **How**: Removed `wallpaper.jpg` from GResource XML and resources directory. `resolve_background_path` returns `Option<PathBuf>`. All wallpaper-related functions handle `None` gracefully. Binary size dropped from ~3.2MB to ~1.3MB.
+
 ## 2026-03-28 – Switch from env_logger to systemd-journal-logger
 
-- **Who**: Ragnar, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: moonlock and moongreet already use systemd-journal-logger. moonset used env_logger which writes to stderr — not useful for a GUI app launched via keybind. Journal integration enables `journalctl -t moonset` and consistent troubleshooting across all three Moon projects.
 - **Tradeoffs**: Requires systemd at runtime. Graceful fallback to eprintln if journal logger fails. Acceptable since Moonarch targets systemd-based Arch Linux.
 - **How**: Replace `env_logger` dep with `systemd-journal-logger`, add `setup_logging()` with `MOONSET_DEBUG` env var for debug-level output. Same pattern as moonlock/moongreet.
 
 ## 2026-03-28 – Replace action name dispatch with `quit_after` field
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: Post-action behavior (quit the app or not) was controlled by comparing `action_name == "lock"` — a magic string duplicated from the action definition. Renaming an action would silently break the dispatch.
 - **Tradeoffs**: Adds a field to `ActionDef` that most actions set to `false`. Acceptable because it makes the contract explicit and testable.
 - **How**: `ActionDef.quit_after: bool` — `true` for lock and logout, `false` for hibernate/reboot/shutdown.
 
 ## 2026-03-28 – GPU blur via GskBlurNode replaces CPU blur
 
-- **Who**: Ragnar, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: CPU-side Gaussian blur (`image` crate) blocked startup and added caching complexity. moonlock already migrated to GPU blur.
 - **Tradeoffs**: GPU blur quality is slightly different (box-blur approximation vs true Gaussian), acceptable for wallpaper backgrounds. Removes `image` crate dependency entirely. No disk cache needed.
 - **How**: `Snapshot::push_blur()` + `GskRenderer::render_texture()` on `connect_realize`. Blur happens once on the GPU when the widget gets its renderer. Symmetric with moonlock and moongreet.
 
 ## 2026-03-28 – Use absolute paths for system binaries
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: Security audit flagged PATH hijacking risk — relative binary names allow a malicious `$PATH` entry to intercept `systemctl`, `loginctl`, etc.
 - **Tradeoffs**: Hardcoded paths reduce portability to non-Arch distros where binaries may live elsewhere (e.g. `/sbin/`). Acceptable because Moonarch targets Arch Linux exclusively.
 - **How**: All five power action wrappers now use `/usr/bin/` prefixed paths.
 
 ## 2026-03-28 – Implement power action timeout via try_wait polling
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: `POWER_TIMEOUT` and `PowerError::Timeout` were declared but never wired up. A hanging `systemctl hibernate` (e.g. blocked NFS mount) would freeze the power menu indefinitely.
 - **Tradeoffs**: Polling with `try_wait()` + 100ms sleep is slightly less efficient than a dedicated timeout crate, but avoids adding a dependency for a single use case.
 - **How**: `run_command` now polls `child.try_wait()` against a 30s deadline, kills the child on timeout.
 
 ## 2026-03-28 – Centralize GRESOURCE_PREFIX
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: The string `/dev/moonarch/moonset` was duplicated in `config.rs`, `users.rs`, and as literal strings in `panel.rs` and `main.rs`. Changing the application ID would require edits in 4+ locations.
 - **Tradeoffs**: Modules now depend on `crate::GRESOURCE_PREFIX` — tighter coupling to main.rs, but acceptable for an internal constant.
 - **How**: Single `pub(crate) const GRESOURCE_PREFIX` in `main.rs`, referenced everywhere else.
 
 ## 2026-03-28 – Remove journal.md
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: One-time development notes from the Rust rewrite, never updated after initial session. Overlapped with memory system and git history.
 - **Tradeoffs**: Historical context lost from the file, but the information is preserved in git history and the memory system.
 - **How**: Deleted. Useful technical learnings migrated to persistent memory.
 
 ## 2026-03-27 – OVERLAY layer instead of TOP
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: Waybar occupies the TOP layer. The power menu must appear above it.
 - **Tradeoffs**: OVERLAY is the highest layer — nothing can render above moonset while it's open. This is intentional for a session power menu.
 - **How**: `setup_layer_shell` uses `gtk4_layer_shell::Layer::Overlay` for the panel window.
 
 ## 2026-03-27 – Lock without confirmation
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: Lock is immediately reversible (just unlock). All other actions (logout, hibernate, reboot, shutdown) are destructive or disruptive.
 - **Tradeoffs**: One less click for the most common action. Risk of accidental lock is negligible since unlocking is trivial.
 - **How**: `ActionDef.needs_confirm = false` for lock; all others require inline confirmation.
 
 ## 2026-03-27 – Niri-specific logout via `niri msg action quit`
 
-- **Who**: Hekate, Dom
+- **Who**: ClaudeCode, Dom
 - **Why**: Moonarch is built exclusively for the Niri compositor. Generic Wayland logout mechanisms don't exist — each compositor has its own.
 - **Tradeoffs**: Hard dependency on Niri. If the compositor changes, `power::logout()` must be updated.
 - **How**: `Command::new("/usr/bin/niri").args(["msg", "action", "quit"])`.

build.rs

@@ -1,5 +1,5 @@
 // ABOUTME: Build script for compiling GResource bundle.
-// ABOUTME: Bundles style.css, wallpaper.jpg, and default-avatar.svg into the binary.
+// ABOUTME: Bundles style.css and default-avatar.svg into the binary.
 
 fn main() {
     glib_build_tools::compile_resources(

resources/resources.gresource.xml

@@ -1,8 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <gresources>
   <gresource prefix="/dev/moonarch/moonset">
-    <file>style.css</file>
-    <file>wallpaper.jpg</file>
-    <file>default-avatar.svg</file>
+    <file compressed="true">style.css</file>
+    <file compressed="true">default-avatar.svg</file>
   </gresource>
 </gresources>

resources/style.css

@@ -27,7 +27,7 @@ window.wallpaper.visible {
 
 /* Round avatar image */
 .avatar {
-    border-radius: 50%;
+    border-radius: 9999px;
     min-width: 128px;
     min-height: 128px;
     background-color: @theme_selected_bg_color;
@@ -48,7 +48,7 @@ window.wallpaper.visible {
     min-width: 120px;
     min-height: 120px;
     padding: 16px;
-    border-radius: 50%;
+    border-radius: 9999px;
     background-color: alpha(@theme_base_color, 0.55);
     color: @theme_fg_color;
     border: none;

src/config.rs

@@ -37,8 +37,11 @@ pub fn load_config(config_paths: Option<&[PathBuf]>) -> Config {
                     if parsed.background_path.is_some() {
                         merged.background_path = parsed.background_path;
                     }
-                    if parsed.background_blur.is_some() {
+                    // Validate blur per source — invalid values preserve the previous default
+                    if parsed.background_blur.is_some_and(|b| b.is_finite() && (0.0..=200.0).contains(&b)) {
                         merged.background_blur = parsed.background_blur;
+                    } else if parsed.background_blur.is_some() {
+                        log::warn!("Invalid background_blur in {}, ignoring", path.display());
                     }
                 }
                 Err(e) => {
@@ -53,32 +56,68 @@ pub fn load_config(config_paths: Option<&[PathBuf]>) -> Config {
 
 /// Resolve the wallpaper path using the fallback hierarchy.
 ///
-/// Priority: config background_path > Moonarch system default > gresource fallback.
-pub fn resolve_background_path(config: &Config) -> PathBuf {
+/// Priority: config background_path > Moonarch system default.
+/// Returns None if no wallpaper is available (CSS background shows through).
+pub fn resolve_background_path(config: &Config) -> Option<PathBuf> {
     resolve_background_path_with(config, Path::new(MOONARCH_WALLPAPER))
 }
 
+/// Wallpapers are passed to gdk-pixbuf's image loader; restrict to common image
+/// extensions to reduce the parser-attack surface for user-controlled paths.
+const ALLOWED_BG_EXT: &[&str] = &["jpg", "jpeg", "png", "webp"];
+
+/// Bound wallpaper decode latency (10 MB covers typical 4K JPEGs at Q95).
+const MAX_WALLPAPER_FILE_SIZE: u64 = 10 * 1024 * 1024;
+
+fn is_allowed_wallpaper(path: &Path) -> bool {
+    match path.extension().and_then(|e| e.to_str()) {
+        Some(ext) => ALLOWED_BG_EXT.iter().any(|a| a.eq_ignore_ascii_case(ext)),
+        None => false,
+    }
+}
+
+fn accept_wallpaper(path: &Path) -> bool {
+    if !is_allowed_wallpaper(path) {
+        log::warn!("Wallpaper rejected (extension not in allowlist): {}", path.display());
+        return false;
+    }
+    match path.symlink_metadata() {
+        Ok(meta) if meta.file_type().is_symlink() => {
+            log::warn!("Wallpaper rejected (symlink): {}", path.display());
+            false
+        }
+        Ok(meta) if !meta.is_file() => false,
+        Ok(meta) if meta.len() > MAX_WALLPAPER_FILE_SIZE => {
+            log::warn!(
+                "Wallpaper rejected ({} bytes > {} limit): {}",
+                meta.len(), MAX_WALLPAPER_FILE_SIZE, path.display()
+            );
+            false
+        }
+        Ok(_) => true,
+        Err(_) => false,
+    }
+}
+
 /// Resolve with configurable moonarch wallpaper path (for testing).
-pub fn resolve_background_path_with(config: &Config, moonarch_wallpaper: &Path) -> PathBuf {
-    // User-configured path
+pub fn resolve_background_path_with(config: &Config, moonarch_wallpaper: &Path) -> Option<PathBuf> {
+    // User-configured path — reject symlinks, non-image extensions, and oversized files
     if let Some(ref bg) = config.background_path {
         let path = PathBuf::from(bg);
-        if path.is_file() {
+        if accept_wallpaper(&path) {
             log::debug!("Wallpaper source: config ({})", path.display());
-            return path;
+            return Some(path);
         }
     }
 
-    // Moonarch ecosystem default
-    if moonarch_wallpaper.is_file() {
+    // Moonarch ecosystem default — apply the same checks for consistency
+    if accept_wallpaper(moonarch_wallpaper) {
         log::debug!("Wallpaper source: moonarch default ({})", moonarch_wallpaper.display());
-        return moonarch_wallpaper.to_path_buf();
+        return Some(moonarch_wallpaper.to_path_buf());
     }
 
-    // GResource fallback path (loaded from compiled resources at runtime)
-    let prefix = crate::GRESOURCE_PREFIX;
-    log::debug!("Wallpaper source: GResource fallback");
-    PathBuf::from(format!("{prefix}/wallpaper.jpg"))
+    log::debug!("No wallpaper found, using CSS background");
+    None
 }
 
 #[cfg(test)]
@@ -164,7 +203,7 @@ mod tests {
         };
         assert_eq!(
             resolve_background_path_with(&config, Path::new("/nonexistent")),
-            wallpaper
+            Some(wallpaper)
         );
     }
 
@@ -175,8 +214,7 @@ mod tests {
             ..Config::default()
         };
         let result = resolve_background_path_with(&config, Path::new("/nonexistent"));
-        // Falls through to gresource fallback
-        assert!(result.to_str().unwrap().contains("moonset"));
+        assert_eq!(result, None);
     }
 
     #[test]
@@ -185,14 +223,14 @@ mod tests {
         let moonarch_wp = dir.path().join("wallpaper.jpg");
         fs::write(&moonarch_wp, "fake").unwrap();
         let config = Config::default();
-        assert_eq!(resolve_background_path_with(&config, &moonarch_wp), moonarch_wp);
+        assert_eq!(resolve_background_path_with(&config, &moonarch_wp), Some(moonarch_wp));
     }
 
     #[test]
-    fn resolve_uses_gresource_fallback_as_last_resort() {
+    fn resolve_returns_none_when_no_wallpaper_available() {
         let config = Config::default();
         let result = resolve_background_path_with(&config, Path::new("/nonexistent"));
-        assert!(result.to_str().unwrap().contains("wallpaper.jpg"));
+        assert_eq!(result, None);
     }
 
     #[test]
@@ -217,12 +255,52 @@ mod tests {
     }
 
     #[test]
-    fn load_config_accepts_negative_blur() {
+    fn load_config_rejects_negative_blur() {
         let dir = tempfile::tempdir().unwrap();
         let conf = dir.path().join("negative.toml");
         fs::write(&conf, "background_blur = -5.0\n").unwrap();
         let paths = vec![conf];
         let config = load_config(Some(&paths));
-        assert_eq!(config.background_blur, Some(-5.0));
+        assert_eq!(config.background_blur, None);
+    }
+
+    #[test]
+    fn load_config_rejects_excessive_blur() {
+        let dir = tempfile::tempdir().unwrap();
+        let conf = dir.path().join("huge.toml");
+        fs::write(&conf, "background_blur = 999.0\n").unwrap();
+        let paths = vec![conf];
+        let config = load_config(Some(&paths));
+        assert_eq!(config.background_blur, None);
+    }
+
+    #[test]
+    fn load_config_accepts_valid_blur_range() {
+        let dir = tempfile::tempdir().unwrap();
+        let conf = dir.path().join("valid.toml");
+        fs::write(&conf, "background_blur = 50.0\n").unwrap();
+        let paths = vec![conf];
+        let config = load_config(Some(&paths));
+        assert_eq!(config.background_blur, Some(50.0));
+    }
+
+    #[test]
+    fn load_config_accepts_zero_blur() {
+        let dir = tempfile::tempdir().unwrap();
+        let conf = dir.path().join("zero.toml");
+        fs::write(&conf, "background_blur = 0.0\n").unwrap();
+        let paths = vec![conf];
+        let config = load_config(Some(&paths));
+        assert_eq!(config.background_blur, Some(0.0));
+    }
+
+    #[test]
+    fn load_config_accepts_max_blur() {
+        let dir = tempfile::tempdir().unwrap();
+        let conf = dir.path().join("max.toml");
+        fs::write(&conf, "background_blur = 200.0\n").unwrap();
+        let paths = vec![conf];
+        let config = load_config(Some(&paths));
+        assert_eq!(config.background_blur, Some(200.0));
     }
 }

src/i18n.rs

@@ -110,11 +110,23 @@ fn read_lang_from_conf(path: &Path) -> Option<String> {
     None
 }
 
-/// Determine the system language from LANG env var or /etc/locale.conf.
+/// Determine the system language from POSIX locale env vars or /etc/locale.conf.
+/// Checks LC_ALL, LC_MESSAGES, LANG in POSIX priority order (LC_ALL overrides
+/// everything; LC_MESSAGES overrides LANG for text categories).
 pub fn detect_locale() -> String {
-    let (raw, source) = if let Some(val) = env::var("LANG").ok().filter(|s| !s.is_empty()) {
-        (Some(val), "LANG env")
-    } else if let Some(val) = read_lang_from_conf(Path::new(DEFAULT_LOCALE_CONF)) {
+    let env_val = env::var("LC_ALL")
+        .ok()
+        .filter(|s| !s.is_empty())
+        .or_else(|| env::var("LC_MESSAGES").ok().filter(|s| !s.is_empty()))
+        .or_else(|| env::var("LANG").ok().filter(|s| !s.is_empty()));
+    detect_locale_with(env_val.as_deref(), Path::new(DEFAULT_LOCALE_CONF))
+}
+
+/// Determine locale with configurable inputs (for testing).
+pub fn detect_locale_with(env_lang: Option<&str>, locale_conf_path: &Path) -> String {
+    let (raw, source) = if let Some(val) = env_lang.filter(|s| !s.is_empty()) {
+        (Some(val.to_string()), "env")
+    } else if let Some(val) = read_lang_from_conf(locale_conf_path) {
         (Some(val), "locale.conf")
     } else {
         (None, "default")
@@ -264,6 +276,40 @@ mod tests {
         }
     }
 
+    // -- detect_locale_with tests --
+
+    #[test]
+    fn detect_locale_uses_env_lang() {
+        let result = detect_locale_with(Some("de_DE.UTF-8"), Path::new("/nonexistent"));
+        assert_eq!(result, "de");
+    }
+
+    #[test]
+    fn detect_locale_falls_back_to_conf_file() {
+        let dir = tempfile::tempdir().unwrap();
+        let conf = dir.path().join("locale.conf");
+        let mut f = fs::File::create(&conf).unwrap();
+        writeln!(f, "LANG=de_DE.UTF-8").unwrap();
+        let result = detect_locale_with(None, &conf);
+        assert_eq!(result, "de");
+    }
+
+    #[test]
+    fn detect_locale_ignores_empty_env_lang() {
+        let dir = tempfile::tempdir().unwrap();
+        let conf = dir.path().join("locale.conf");
+        let mut f = fs::File::create(&conf).unwrap();
+        writeln!(f, "LANG=fr_FR.UTF-8").unwrap();
+        let result = detect_locale_with(Some(""), &conf);
+        assert_eq!(result, "fr");
+    }
+
+    #[test]
+    fn detect_locale_defaults_to_english() {
+        let result = detect_locale_with(None, Path::new("/nonexistent"));
+        assert_eq!(result, "en");
+    }
+
     #[test]
     fn error_messages_contain_failed() {
         let s = load_strings(Some("en"));

src/main.rs

@@ -11,6 +11,7 @@ use gdk4 as gdk;
 use gtk4::prelude::*;
 use gtk4::{self as gtk, gio};
 use gtk4_layer_shell::LayerShell;
+use std::path::PathBuf;
 
 pub(crate) const GRESOURCE_PREFIX: &str = "/dev/moonarch/moonset";
 
@@ -20,7 +21,7 @@ fn load_css(display: &gdk::Display) {
     gtk::style_context_add_provider_for_display(
         display,
         &css_provider,
-        gtk::STYLE_PROVIDER_PRIORITY_APPLICATION,
+        gtk::STYLE_PROVIDER_PRIORITY_USER,
     );
 }
 
@@ -42,7 +43,7 @@ fn setup_layer_shell(
     window.set_anchor(gtk4_layer_shell::Edge::Right, true);
 }
 
-fn activate(app: &gtk::Application) {
+fn activate(app: &gtk::Application, bg_path: &Option<PathBuf>, blur_radius: Option<f32>) {
     let display = match gdk::Display::default() {
         Some(d) => d,
         None => {
@@ -53,16 +54,14 @@ fn activate(app: &gtk::Application) {
 
     load_css(&display);
 
-    // Resolve wallpaper once, decode texture once, share across all windows.
+    // Decode texture once (if wallpaper available), share across all windows.
     // Blur is applied on the GPU via GskBlurNode at first widget realization,
     // then cached and reused by all subsequent windows.
-    let config = config::load_config(None);
-    let bg_path = config::resolve_background_path(&config);
-    let texture = panel::load_background_texture(&bg_path);
+    let texture = panel::load_background_texture(bg_path.as_deref());
     let blur_cache = panel::new_blur_cache();
 
     // Panel on focused output (no set_monitor → compositor picks focused)
-    let panel = panel::create_panel_window(&texture, config.background_blur, &blur_cache, app);
+    let panel = panel::create_panel_window(texture.as_ref(), blur_radius, &blur_cache, app);
     setup_layer_shell(&panel, true, gtk4_layer_shell::Layer::Overlay);
     panel.present();
 
@@ -70,7 +69,7 @@ fn activate(app: &gtk::Application) {
     let monitors = display.monitors();
     for i in 0..monitors.n_items() {
         if let Some(monitor) = monitors.item(i).and_then(|obj| obj.downcast::<gdk::Monitor>().ok()) {
-            let wallpaper = panel::create_wallpaper_window(&texture, config.background_blur, &blur_cache, app);
+            let wallpaper = panel::create_wallpaper_window(texture.as_ref(), blur_radius, &blur_cache, app);
             setup_layer_shell(&wallpaper, false, gtk4_layer_shell::Layer::Top);
             wallpaper.set_monitor(Some(&monitor));
             wallpaper.present();
@@ -89,10 +88,12 @@ fn setup_logging() {
             eprintln!("Failed to create journal logger: {e}");
         }
     }
-    let level = if std::env::var("MOONSET_DEBUG").is_ok() {
-        log::LevelFilter::Debug
-    } else {
-        log::LevelFilter::Info
+    // Require MOONSET_DEBUG=1 to raise verbosity so mere presence (empty
+    // value in a session script) cannot escalate journal noise with path
+    // information an attacker could use.
+    let level = match std::env::var("MOONSET_DEBUG").ok().as_deref() {
+        Some("1") => log::LevelFilter::Debug,
+        _ => log::LevelFilter::Info,
     };
     log::set_max_level(level);
 }
@@ -104,10 +105,16 @@ fn main() {
     // Register compiled GResources
     gio::resources_register_include!("moonset.gresource").expect("Failed to register resources");
 
+    // Load config and resolve wallpaper path before GTK app start —
+    // no GTK types needed, avoids blocking the main loop.
+    let config = config::load_config(None);
+    let bg_path = config::resolve_background_path(&config);
+    let blur_radius = config.background_blur;
+
     let app = gtk::Application::builder()
         .application_id("dev.moonarch.moonset")
         .build();
 
-    app.connect_activate(activate);
+    app.connect_activate(move |app| activate(app, &bg_path, blur_radius));
     app.run();
 }

src/panel.rs

@@ -7,7 +7,7 @@ use glib::clone;
 use gtk4::prelude::*;
 use gtk4::{self as gtk, gio};
 use std::cell::RefCell;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use std::rc::Rc;
 use std::time::Duration;
 
@@ -87,25 +87,38 @@ pub fn action_definitions() -> Vec<ActionDef> {
 }
 
 /// Load the wallpaper as a texture once, for sharing across all windows.
-/// Blur is applied on the GPU via GskBlurNode at widget realization time.
-pub fn load_background_texture(bg_path: &Path) -> gdk::Texture {
-    let fallback = format!("{}/wallpaper.jpg", crate::GRESOURCE_PREFIX);
-
+/// Returns None if no wallpaper path is configured (CSS background shows through).
+pub fn load_background_texture(bg_path: Option<&Path>) -> Option<gdk::Texture> {
+    let bg_path = bg_path?;
     log::debug!("Background: {}", bg_path.display());
-    if bg_path.starts_with(crate::GRESOURCE_PREFIX) {
-        let resource_path = bg_path.to_str().unwrap_or(&fallback);
-        gdk::Texture::from_resource(resource_path)
-    } else {
-        let file = gio::File::for_path(bg_path);
-        gdk::Texture::from_file(&file).unwrap_or_else(|_| {
-            gdk::Texture::from_resource(&fallback)
-        })
+    let file = gio::File::for_path(bg_path);
+    match gdk::Texture::from_file(&file) {
+        Ok(texture) => Some(texture),
+        Err(e) => {
+            log::warn!("Failed to load wallpaper {}: {e}", bg_path.display());
+            None
+        }
     }
 }
 
 // -- GPU blur via GskBlurNode -------------------------------------------------
 
+// SYNC: MAX_BLUR_DIMENSION, render_blurred_texture, and create_background_picture
+// are duplicated in moonlock/src/lockscreen.rs and moongreet/src/greeter.rs.
+// Changes here must be mirrored to the other two projects.
+
+/// Maximum texture dimension before downscaling for blur.
+/// Keeps GPU work reasonable on 4K+ displays.
+const MAX_BLUR_DIMENSION: f32 = 1920.0;
+
 /// Render a blurred texture using the GPU via GskBlurNode.
+///
+/// To avoid edge darkening (blur samples transparent pixels outside bounds),
+/// the texture is rendered with padding equal to 3x the blur sigma. The blur
+/// is applied to the padded area, then cropped back to the original size.
+///
+/// Large textures (> MAX_BLUR_DIMENSION) are downscaled before blurring to
+/// reduce GPU work. The sigma is scaled proportionally.
 fn render_blurred_texture(
     widget: &impl IsA<gtk::Widget>,
     texture: &gdk::Texture,
@@ -113,15 +126,36 @@ fn render_blurred_texture(
 ) -> Option<gdk::Texture> {
     let native = widget.native()?;
     let renderer = native.renderer()?;
+
+    let orig_w = texture.width() as f32;
+    let orig_h = texture.height() as f32;
+
+    // Downscale large textures to reduce GPU blur work
+    let max_dim = orig_w.max(orig_h);
+    let scale = if max_dim > MAX_BLUR_DIMENSION {
+        MAX_BLUR_DIMENSION / max_dim
+    } else {
+        1.0
+    };
+    let w = (orig_w * scale).round();
+    let h = (orig_h * scale).round();
+    let scaled_sigma = sigma * scale;
+
+    // Padding must cover the blur kernel radius (typically ~3x sigma)
+    let pad = (scaled_sigma * 3.0).ceil();
+
     let snapshot = gtk::Snapshot::new();
-    let bounds = graphene_rs::Rect::new(
-        0.0, 0.0, texture.width() as f32, texture.height() as f32,
-    );
-    snapshot.push_blur(sigma as f64);
-    snapshot.append_texture(texture, &bounds);
-    snapshot.pop();
+    // Clip output to scaled texture size
+    snapshot.push_clip(&graphene_rs::Rect::new(pad, pad, w, h));
+    snapshot.push_blur(scaled_sigma as f64);
+    // Render texture with padding on all sides (edges repeat via oversized bounds)
+    snapshot.append_texture(texture, &graphene_rs::Rect::new(-pad, -pad, w + 2.0 * pad, h + 2.0 * pad));
+    snapshot.pop(); // blur
+    snapshot.pop(); // clip
+
     let node = snapshot.to_node()?;
-    Some(renderer.render_texture(&node, None))
+    let viewport = graphene_rs::Rect::new(pad, pad, w, h);
+    Some(renderer.render_texture(&node, Some(&viewport)))
 }
 
 /// Fade out all windows and quit the app after the CSS transition completes.
@@ -141,14 +175,16 @@ pub fn new_blur_cache() -> BlurCache {
 }
 
 /// Create a wallpaper-only window for secondary monitors.
-pub fn create_wallpaper_window(texture: &gdk::Texture, blur_radius: Option<f32>, blur_cache: &BlurCache, app: &gtk::Application) -> gtk::ApplicationWindow {
+pub fn create_wallpaper_window(texture: Option<&gdk::Texture>, blur_radius: Option<f32>, blur_cache: &BlurCache, app: &gtk::Application) -> gtk::ApplicationWindow {
     let window = gtk::ApplicationWindow::builder()
         .application(app)
         .build();
     window.add_css_class("wallpaper");
 
-    let background = create_background_picture(texture, blur_radius, blur_cache);
-    window.set_child(Some(&background));
+    if let Some(texture) = texture {
+        let background = create_background_picture(texture, blur_radius, blur_cache);
+        window.set_child(Some(&background));
+    }
 
     // Fade-in on map
     window.connect_map(|w| {
@@ -165,18 +201,23 @@ pub fn create_wallpaper_window(texture: &gdk::Texture, blur_radius: Option<f32>,
 }
 
 /// Create the main panel window with action buttons and confirm flow.
-pub fn create_panel_window(texture: &gdk::Texture, blur_radius: Option<f32>, blur_cache: &BlurCache, app: &gtk::Application) -> gtk::ApplicationWindow {
+pub fn create_panel_window(texture: Option<&gdk::Texture>, blur_radius: Option<f32>, blur_cache: &BlurCache, app: &gtk::Application) -> gtk::ApplicationWindow {
     let window = gtk::ApplicationWindow::builder()
         .application(app)
         .build();
     window.add_css_class("panel");
 
     let strings = load_strings(None);
-    let user = users::get_current_user().unwrap_or_else(|| users::User {
-        username: "user".to_string(),
-        display_name: "User".to_string(),
-        home: dirs::home_dir().unwrap_or_default(),
-        uid: u32::MAX,
+    let user = users::get_current_user().unwrap_or_else(|| {
+        let home = dirs::home_dir().unwrap_or_else(|| {
+            log::warn!("Could not resolve HOME — using an empty path");
+            PathBuf::new()
+        });
+        users::User {
+            username: "user".to_string(),
+            display_name: "User".to_string(),
+            home,
+        }
     });
     log::debug!("User: {} ({})", user.display_name, user.username);
 
@@ -187,9 +228,11 @@ pub fn create_panel_window(texture: &gdk::Texture, blur_radius: Option<f32>, blu
     let overlay = gtk::Overlay::new();
     window.set_child(Some(&overlay));
 
-    // Background wallpaper
-    let background = create_background_picture(texture, blur_radius, blur_cache);
-    overlay.set_child(Some(&background));
+    // Background wallpaper (if available, otherwise CSS background shows through)
+    if let Some(texture) = texture {
+        let background = create_background_picture(texture, blur_radius, blur_cache);
+        overlay.set_child(Some(&background));
+    }
 
     // Click on background dismisses the menu
     let click_controller = gtk::GestureClick::new();
@@ -200,7 +243,7 @@ pub fn create_panel_window(texture: &gdk::Texture, blur_radius: Option<f32>, blu
             fade_out_and_quit(&app);
         }
     ));
-    background.add_controller(click_controller);
+    overlay.add_controller(click_controller);
 
     // Centered content box
     let content_box = gtk::Box::new(gtk::Orientation::Vertical, 0);
@@ -254,6 +297,7 @@ pub fn create_panel_window(texture: &gdk::Texture, blur_radius: Option<f32>, blu
             &confirm_area,
             &confirm_box,
             &error_label,
+            &button_box,
         );
         button_box.append(&button);
     }
@@ -337,6 +381,7 @@ fn create_action_button(
     confirm_area: &gtk::Box,
     confirm_box: &Rc<RefCell<Option<gtk::Box>>>,
     error_label: &gtk::Label,
+    button_box: &gtk::Box,
 ) -> gtk::Button {
     let button_content = gtk::Box::new(gtk::Orientation::Vertical, 4);
     button_content.set_halign(gtk::Align::Center);
@@ -366,6 +411,8 @@ fn create_action_button(
         confirm_box,
         #[weak]
         error_label,
+        #[weak]
+        button_box,
         move |_| {
             on_action_clicked(
                 &action_def,
@@ -374,6 +421,7 @@ fn create_action_button(
                 &confirm_area,
                 &confirm_box,
                 &error_label,
+                &button_box,
             );
         }
     ));
@@ -396,16 +444,17 @@ fn on_action_clicked(
     confirm_area: &gtk::Box,
     confirm_box: &Rc<RefCell<Option<gtk::Box>>>,
     error_label: &gtk::Label,
+    button_box: &gtk::Box,
 ) {
     dismiss_confirm(confirm_area, confirm_box);
     error_label.set_visible(false);
 
     if !action_def.needs_confirm {
-        execute_action(action_def, strings, app, confirm_area, confirm_box, error_label);
+        execute_action(action_def, strings, app, confirm_area, confirm_box, error_label, button_box);
         return;
     }
 
-    show_confirm(action_def, strings, app, confirm_area, confirm_box, error_label);
+    show_confirm(action_def, strings, app, confirm_area, confirm_box, error_label, button_box);
 }
 
 /// Show inline confirmation below the action buttons.
@@ -416,6 +465,7 @@ fn show_confirm(
     confirm_area: &gtk::Box,
     confirm_box: &Rc<RefCell<Option<gtk::Box>>>,
     error_label: &gtk::Label,
+    button_box: &gtk::Box,
 ) {
     let new_box = gtk::Box::new(gtk::Orientation::Vertical, 8);
     new_box.set_halign(gtk::Align::Center);
@@ -443,6 +493,8 @@ fn show_confirm(
         confirm_box,
         #[weak]
         error_label,
+        #[weak]
+        button_box,
         move |_| {
             execute_action(
                 &action_def_clone,
@@ -451,6 +503,7 @@ fn show_confirm(
                 &confirm_area,
                 &confirm_box,
                 &error_label,
+                &button_box,
             );
         }
     ));
@@ -463,8 +516,13 @@ fn show_confirm(
         confirm_area,
         #[strong]
         confirm_box,
+        #[weak]
+        button_box,
         move |_| {
             dismiss_confirm(&confirm_area, &confirm_box);
+            if let Some(first) = button_box.first_child() {
+                first.grab_focus();
+            }
         }
     ));
     button_row.append(&no_btn);
@@ -493,6 +551,7 @@ fn execute_action(
     confirm_area: &gtk::Box,
     confirm_box: &Rc<RefCell<Option<gtk::Box>>>,
     error_label: &gtk::Label,
+    button_box: &gtk::Box,
 ) {
     dismiss_confirm(confirm_area, confirm_box);
     log::debug!("Executing power action: {}", action_def.name);
@@ -502,6 +561,10 @@ fn execute_action(
     let quit_after = action_def.quit_after;
     let error_message = (action_def.error_attr)(strings).to_string();
 
+    // Desensitize buttons so a double-click or accidental keyboard repeat
+    // cannot fire the same action twice while it is in flight.
+    button_box.set_sensitive(false);
+
     // Use glib::spawn_future_local + gio::spawn_blocking to avoid Send issues
     // with GTK objects. The blocking closure runs on a thread pool, the result
     // is handled back on the main thread.
@@ -510,24 +573,30 @@ fn execute_action(
         app,
         #[weak]
         error_label,
+        #[weak]
+        button_box,
         async move {
-            let result = gio::spawn_blocking(move || action_fn()).await;
+            let result = gio::spawn_blocking(action_fn).await;
 
             match result {
                 Ok(Ok(())) => {
                     if quit_after {
                         fade_out_and_quit(&app);
+                    } else {
+                        button_box.set_sensitive(true);
                     }
                 }
                 Ok(Err(e)) => {
                     log::error!("Power action '{}' failed: {}", action_name, e);
                     error_label.set_text(&error_message);
                     error_label.set_visible(true);
+                    button_box.set_sensitive(true);
                 }
                 Err(_) => {
                     log::error!("Power action '{}' panicked", action_name);
                     error_label.set_text(&error_message);
                     error_label.set_visible(true);
+                    button_box.set_sensitive(true);
                 }
             }
         }

src/power.rs

@@ -4,7 +4,9 @@
 use std::fmt;
 use std::io::Read;
 use std::process::{Command, Stdio};
-use std::time::{Duration, Instant};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Arc;
+use std::time::Duration;
 
 const POWER_TIMEOUT: Duration = Duration::from_secs(30);
 
@@ -30,11 +32,17 @@ impl fmt::Display for PowerError {
 impl std::error::Error for PowerError {}
 
 /// Run a command with timeout and return a PowerError on failure.
+///
+/// Uses blocking `child.wait()` with a separate timeout thread that sends
+/// SIGKILL after POWER_TIMEOUT. This runs inside `gio::spawn_blocking`,
+/// so blocking is expected.
 fn run_command(action: &'static str, program: &str, args: &[&str]) -> Result<(), PowerError> {
     log::debug!("Power action: {action} ({program} {args:?})");
     let mut child = Command::new(program)
         .args(args)
-        .stdout(Stdio::piped())
+        // stdout is discarded — piping without draining would deadlock if a
+        // command ever wrote more than one OS pipe buffer before wait() returned.
+        .stdout(Stdio::null())
         .stderr(Stdio::piped())
         .spawn()
         .map_err(|e| PowerError::CommandFailed {
@@ -42,40 +50,60 @@ fn run_command(action: &'static str, program: &str, args: &[&str]) -> Result<(),
             message: e.to_string(),
         })?;
 
-    let deadline = Instant::now() + POWER_TIMEOUT;
-    loop {
-        match child.try_wait() {
-            Ok(Some(status)) => {
-                if status.success() {
-                    log::debug!("Power action {action} completed");
-                }
-                if !status.success() {
-                    let mut stderr_buf = String::new();
-                    if let Some(mut stderr) = child.stderr.take() {
-                        let _ = stderr.read_to_string(&mut stderr_buf);
-                    }
-                    return Err(PowerError::CommandFailed {
-                        action,
-                        message: format!("exit code {}: {}", status, stderr_buf.trim()),
-                    });
-                }
-                return Ok(());
-            }
-            Ok(None) => {
-                if Instant::now() >= deadline {
-                    let _ = child.kill();
-                    let _ = child.wait();
-                    return Err(PowerError::Timeout { action });
-                }
-                std::thread::sleep(Duration::from_millis(100));
-            }
-            Err(e) => {
-                return Err(PowerError::CommandFailed {
-                    action,
-                    message: e.to_string(),
-                });
+    let child_pid = nix::unistd::Pid::from_raw(child.id() as i32);
+    let done = Arc::new(AtomicBool::new(false));
+    let timed_out = Arc::new(AtomicBool::new(false));
+    let done_clone = done.clone();
+    let timed_out_clone = timed_out.clone();
+
+    let _timeout_thread = std::thread::spawn(move || {
+        let interval = Duration::from_millis(100);
+        let mut elapsed = Duration::ZERO;
+        while elapsed < POWER_TIMEOUT {
+            std::thread::sleep(interval);
+            if done_clone.load(Ordering::Acquire) {
+                return;
             }
+            elapsed += interval;
         }
+        // Record that we fired the kill so we don't misclassify an external
+        // SIGKILL (OOM killer, kill -9) as our timeout.
+        timed_out_clone.store(true, Ordering::Release);
+        // ESRCH if the process already exited — harmless
+        let _ = nix::sys::signal::kill(child_pid, nix::sys::signal::Signal::SIGKILL);
+    });
+
+    // Drop guard ensures the timeout thread sees done=true even if child.wait()
+    // errors out — otherwise the thread sleeps its full 30 s holding a slot in
+    // the gio::spawn_blocking pool.
+    struct DoneGuard(Arc<AtomicBool>);
+    impl Drop for DoneGuard {
+        fn drop(&mut self) {
+            self.0.store(true, Ordering::Release);
+        }
+    }
+    let _done_guard = DoneGuard(done);
+
+    let status = child.wait().map_err(|e| PowerError::CommandFailed {
+        action,
+        message: e.to_string(),
+    })?;
+
+    if status.success() {
+        log::debug!("Power action {action} completed");
+        Ok(())
+    } else {
+        if timed_out.load(Ordering::Acquire) {
+            return Err(PowerError::Timeout { action });
+        }
+        let mut stderr_buf = String::new();
+        if let Some(mut stderr) = child.stderr.take() {
+            let _ = stderr.read_to_string(&mut stderr_buf);
+        }
+        Err(PowerError::CommandFailed {
+            action,
+            message: format!("exit code {}: {}", status, stderr_buf.trim()),
+        })
     }
 }
 
@@ -87,7 +115,7 @@ pub fn lock() -> Result<(), PowerError> {
     Command::new("/usr/bin/moonlock")
         .stdin(Stdio::null())
         .stdout(Stdio::null())
-        .stderr(Stdio::null())
+        .stderr(Stdio::inherit())
         .spawn()
         .map_err(|e| PowerError::CommandFailed {
             action: "lock",
@@ -107,14 +135,14 @@ pub fn hibernate() -> Result<(), PowerError> {
     run_command("hibernate", "/usr/bin/systemctl", &["hibernate"])
 }
 
-/// Reboot the system via loginctl.
+/// Reboot the system via systemctl.
 pub fn reboot() -> Result<(), PowerError> {
-    run_command("reboot", "/usr/bin/loginctl", &["reboot"])
+    run_command("reboot", "/usr/bin/systemctl", &["reboot"])
 }
 
-/// Shut down the system via loginctl.
+/// Shut down the system via systemctl.
 pub fn shutdown() -> Result<(), PowerError> {
-    run_command("shutdown", "/usr/bin/loginctl", &["poweroff"])
+    run_command("shutdown", "/usr/bin/systemctl", &["poweroff"])
 }
 
 #[cfg(test)]

src/users.rs

@@ -12,7 +12,6 @@ pub struct User {
     pub username: String,
     pub display_name: String,
     pub home: PathBuf,
-    pub uid: u32,
 }
 
 /// Get the currently logged-in user's info from the system.
@@ -37,7 +36,6 @@ pub fn get_current_user() -> Option<User> {
         username: nix_user.name,
         display_name,
         home: nix_user.dir,
-        uid: uid.as_raw(),
     })
 }
 
@@ -47,6 +45,7 @@ pub fn get_avatar_path(home: &Path, username: Option<&str>) -> Option<PathBuf> {
 }
 
 /// Find avatar with configurable AccountsService dir (for testing).
+/// Rejects symlinks to prevent path traversal.
 pub fn get_avatar_path_with(
     home: &Path,
     username: Option<&str>,
@@ -54,17 +53,25 @@ pub fn get_avatar_path_with(
 ) -> Option<PathBuf> {
     // ~/.face takes priority
     let face = home.join(".face");
-    if face.exists() {
-        log::debug!("Avatar: using ~/.face");
-        return Some(face);
+    if let Ok(meta) = face.symlink_metadata() {
+        if meta.file_type().is_symlink() {
+            log::warn!("Rejecting symlink avatar: {}", face.display());
+        } else if meta.is_file() {
+            log::debug!("Avatar: using ~/.face ({})", face.display());
+            return Some(face);
+        }
     }
 
-    // AccountsService icon
-    if let Some(name) = username {
-        if accountsservice_dir.exists() {
-            let icon = accountsservice_dir.join(name);
-            if icon.exists() {
-                log::debug!("Avatar: using AccountsService icon");
+    // AccountsService icon fallback
+    if let Some(name) = username
+        && accountsservice_dir.exists()
+    {
+        let icon = accountsservice_dir.join(name);
+        if let Ok(meta) = icon.symlink_metadata() {
+            if meta.file_type().is_symlink() {
+                log::warn!("Rejecting symlink avatar: {}", icon.display());
+            } else if meta.is_file() {
+                log::debug!("Avatar: using AccountsService icon ({})", icon.display());
                 return Some(icon);
             }
         }
@@ -127,6 +134,17 @@ mod tests {
         assert_eq!(path, Some(face));
     }
 
+    #[test]
+    fn rejects_symlink_avatar() {
+        let dir = tempfile::tempdir().unwrap();
+        let target = dir.path().join("secret");
+        fs::write(&target, "secret content").unwrap();
+        let face = dir.path().join(".face");
+        std::os::unix::fs::symlink(&target, &face).unwrap();
+        let path = get_avatar_path_with(dir.path(), None, Path::new("/nonexistent"));
+        assert!(path.is_none());
+    }
+
     #[test]
     fn returns_none_when_no_avatar() {
         let dir = tempfile::tempdir().unwrap();