fix(settings): harden Torrent network validation

- Align the DHT message-timeout range with bundled Aria2 1.37.0.
- Validate and canonicalize Torrent network text settings at the native boundary.
- Fence delayed input responses and reject contradictory IPv6 bind state.
- Add regression coverage for malformed settings and cross-field races.

src/components/SettingsView.tsx

@@ -34,6 +34,7 @@ import {
 import { usePlatformInfo } from '../utils/platform';
 import { isTrustedFirelinkReleaseUrl } from '../utils/releaseUrls';
 import { normalizeCustomProxy } from '../store/useDownloadStore';
+import { shouldApplyTorrentNetworkInputResult } from '../utils/torrentNetworkInput';
 import {
   DEFAULT_TORRENT_DHT_MESSAGE_TIMEOUT,
   MAX_TORRENT_DHT_MESSAGE_TIMEOUT,
@@ -99,6 +100,105 @@ type ManualUpdateStatus =
 
 type SystemProxyStatus = 'idle' | 'checking' | 'detected' | 'none' | 'error';
 
+type TorrentNetworkTextField =
+  | 'torrentListenPort'
+  | 'torrentDhtListenPort'
+  | 'torrentExternalIp'
+  | 'torrentDhtEntryPoint'
+  | 'torrentDhtEntryPoint6'
+  | 'torrentDhtListenAddr6'
+  | 'torrentLpdInterface'
+  | 'torrentPeerIdPrefix'
+  | 'torrentPeerAgent'
+  | 'torrentBindAddress'
+  | 'aria2DiskCache';
+
+const TorrentNetworkTextInput = ({
+  field,
+  value,
+  label,
+  description,
+  placeholder,
+  onCommit,
+  onError,
+  maxLength,
+  className = 'app-control settings-network-input'
+}: {
+  field: TorrentNetworkTextField;
+  value: string;
+  label: string;
+  description: string;
+  placeholder?: string;
+  onCommit: (value: string) => boolean | void;
+  onError: (error: unknown) => void;
+  maxLength?: number;
+  className?: string;
+}) => {
+  const [draft, setDraft] = useState(value);
+  const commitId = useRef(0);
+  const editId = useRef(0);
+
+  useEffect(() => {
+    editId.current += 1;
+    setDraft(value);
+  }, [value]);
+
+  const commit = async () => {
+    const requestId = ++commitId.current;
+    const editRequestId = editId.current;
+    try {
+      const normalized = await invoke('canonicalize_torrent_network_setting', {
+        field,
+        value: draft
+      });
+      if (!shouldApplyTorrentNetworkInputResult(
+        requestId,
+        commitId.current,
+        editRequestId,
+        editId.current
+      )) return;
+      if (onCommit(normalized) === false) {
+        setDraft(value);
+        onError(new Error('This Torrent network value conflicts with another setting.'));
+        return;
+      }
+      setDraft(normalized);
+    } catch (error) {
+      if (!shouldApplyTorrentNetworkInputResult(
+        requestId,
+        commitId.current,
+        editRequestId,
+        editId.current
+      )) return;
+      setDraft(value);
+      onError(error);
+    }
+  };
+
+  return (
+    <div className="mac-settings-row settings-network-row">
+      <div className="settings-row-label">
+        <span>{label}</span>
+        <small>{description}</small>
+      </div>
+      <input
+        type="text"
+        dir="ltr"
+        value={draft}
+        onChange={(event) => {
+          editId.current += 1;
+          setDraft(event.target.value);
+        }}
+        onBlur={() => { void commit(); }}
+        placeholder={placeholder}
+        maxLength={maxLength}
+        className={className}
+        aria-label={label}
+      />
+    </div>
+  );
+};
+
 export type NetworkSettingsSection = 'general' | 'discovery' | 'connection' | 'limits' | 'advanced';
 
 const networkSettingsSections: NetworkSettingsSection[] = [
@@ -420,6 +520,15 @@ const engineRunId = useRef(0);
 
   // Toast notifications
   const { addToast } = useToast();
+  const showTorrentNetworkInputError = (error: unknown) => {
+    addToast({
+      message: t($ => $.settings.network.torrentNetworkInputInvalid, {
+        detail: error instanceof Error ? error.message : String(error)
+      }),
+      variant: 'error',
+      isActionable: true
+    });
+  };
   const commitTorrentMaxOpenFiles = (raw: string) => {
     const next = normalizeTorrentMaxOpenFiles(raw) ?? settings.torrentMaxOpenFiles;
     const requestId = ++torrentMaxOpenFilesCommitRef.current;
@@ -1442,148 +1551,100 @@ runEngineChecks(false);
               <div id="network-settings-panel-connection" role="tabpanel" aria-labelledby="network-settings-tab-connection" hidden={networkSection !== 'connection'} tabIndex={0}>
               <h2 className="settings-section-title">{t($ => $.settings.network.torrentNetwork)}</h2>
               <div className="mac-settings-group">
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentListenPort)}</span>
-                    <small>{t($ => $.settings.network.torrentListenPortDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentListenPort}
-                    onChange={(event) => settings.setTorrentListenPort(event.target.value)}
-                    placeholder="6881-6999"
-                    className="app-control settings-port-input text-center"
-                    aria-label={t($ => $.settings.network.torrentListenPort)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentBindAddress)}</span>
-                    <small>{t($ => $.settings.network.torrentBindAddressDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentBindAddress}
-                    onChange={(event) => settings.setTorrentBindAddress(event.target.value)}
-                    placeholder="192.0.2.10 or 2001:db8::10"
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentBindAddress)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentDhtListenPort)}</span>
-                    <small>{t($ => $.settings.network.torrentDhtListenPortDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentDhtListenPort}
-                    onChange={(event) => settings.setTorrentDhtListenPort(event.target.value)}
-                    placeholder="6881-6999"
-                    className="app-control settings-port-input text-center"
-                    aria-label={t($ => $.settings.network.torrentDhtListenPort)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentExternalIp)}</span>
-                    <small>{t($ => $.settings.network.torrentExternalIpDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentExternalIp}
-                    onChange={(event) => settings.setTorrentExternalIp(event.target.value)}
-                    placeholder={t($ => $.settings.network.torrentExternalIpPlaceholder)}
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentExternalIp)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentDhtEntryPoint)}</span>
-                    <small>{t($ => $.settings.network.torrentDhtEntryPointDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentDhtEntryPoint}
-                    onChange={(event) => settings.setTorrentDhtEntryPoint(event.target.value)}
-                    placeholder="router.example:6881"
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentDhtEntryPoint)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentDhtEntryPoint6)}</span>
-                    <small>{t($ => $.settings.network.torrentDhtEntryPoint6Description)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentDhtEntryPoint6}
-                    onChange={(event) => settings.setTorrentDhtEntryPoint6(event.target.value)}
-                    placeholder="[2001:db8::1]:6881"
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentDhtEntryPoint6)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentDhtListenAddr6)}</span>
-                    <small>{t($ => $.settings.network.torrentDhtListenAddr6Description)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentDhtListenAddr6}
-                    onChange={(event) => settings.setTorrentDhtListenAddr6(event.target.value)}
-                    placeholder="2001:db8::2"
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentDhtListenAddr6)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentLpdInterface)}</span>
-                    <small>{t($ => $.settings.network.torrentLpdInterfaceDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentLpdInterface}
-                    onChange={(event) => settings.setTorrentLpdInterface(event.target.value)}
-                    placeholder="en0"
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentLpdInterface)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentPeerIdPrefix)}</span>
-                    <small>{t($ => $.settings.network.torrentPeerIdPrefixDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentPeerIdPrefix}
-                    onChange={(event) => settings.setTorrentPeerIdPrefix(event.target.value)}
-                    placeholder="-FL-1-3-1-"
-                    maxLength={20}
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentPeerIdPrefix)}
-                  />
-                </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.torrentPeerAgent)}</span>
-                    <small>{t($ => $.settings.network.torrentPeerAgentDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.torrentPeerAgent}
-                    onChange={(event) => settings.setTorrentPeerAgent(event.target.value)}
-                    placeholder="Firelink/1.3.1"
-                    maxLength={128}
-                    className="app-control settings-network-input"
-                    aria-label={t($ => $.settings.network.torrentPeerAgent)}
-                  />
-                </div>
+                <TorrentNetworkTextInput
+                  field="torrentListenPort"
+                  value={settings.torrentListenPort}
+                  label={t($ => $.settings.network.torrentListenPort)}
+                  description={t($ => $.settings.network.torrentListenPortDescription)}
+                  placeholder="6881-6999"
+                  onCommit={settings.setTorrentListenPort}
+                  onError={showTorrentNetworkInputError}
+                  className="app-control settings-port-input text-center"
+                />
+                <TorrentNetworkTextInput
+                  field="torrentBindAddress"
+                  value={settings.torrentBindAddress}
+                  label={t($ => $.settings.network.torrentBindAddress)}
+                  description={t($ => $.settings.network.torrentBindAddressDescription)}
+                  placeholder="192.0.2.10 or 2001:db8::10"
+                  onCommit={settings.setTorrentBindAddress}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentDhtListenPort"
+                  value={settings.torrentDhtListenPort}
+                  label={t($ => $.settings.network.torrentDhtListenPort)}
+                  description={t($ => $.settings.network.torrentDhtListenPortDescription)}
+                  placeholder="6881-6999"
+                  onCommit={settings.setTorrentDhtListenPort}
+                  onError={showTorrentNetworkInputError}
+                  className="app-control settings-port-input text-center"
+                />
+                <TorrentNetworkTextInput
+                  field="torrentExternalIp"
+                  value={settings.torrentExternalIp}
+                  label={t($ => $.settings.network.torrentExternalIp)}
+                  description={t($ => $.settings.network.torrentExternalIpDescription)}
+                  placeholder={t($ => $.settings.network.torrentExternalIpPlaceholder)}
+                  onCommit={settings.setTorrentExternalIp}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentDhtEntryPoint"
+                  value={settings.torrentDhtEntryPoint}
+                  label={t($ => $.settings.network.torrentDhtEntryPoint)}
+                  description={t($ => $.settings.network.torrentDhtEntryPointDescription)}
+                  placeholder="router.example:6881"
+                  onCommit={settings.setTorrentDhtEntryPoint}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentDhtEntryPoint6"
+                  value={settings.torrentDhtEntryPoint6}
+                  label={t($ => $.settings.network.torrentDhtEntryPoint6)}
+                  description={t($ => $.settings.network.torrentDhtEntryPoint6Description)}
+                  placeholder="[2001:db8::1]:6881"
+                  onCommit={settings.setTorrentDhtEntryPoint6}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentDhtListenAddr6"
+                  value={settings.torrentDhtListenAddr6}
+                  label={t($ => $.settings.network.torrentDhtListenAddr6)}
+                  description={t($ => $.settings.network.torrentDhtListenAddr6Description)}
+                  placeholder="2001:db8::2"
+                  onCommit={settings.setTorrentDhtListenAddr6}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentLpdInterface"
+                  value={settings.torrentLpdInterface}
+                  label={t($ => $.settings.network.torrentLpdInterface)}
+                  description={t($ => $.settings.network.torrentLpdInterfaceDescription)}
+                  placeholder="en0"
+                  onCommit={settings.setTorrentLpdInterface}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentPeerIdPrefix"
+                  value={settings.torrentPeerIdPrefix}
+                  label={t($ => $.settings.network.torrentPeerIdPrefix)}
+                  description={t($ => $.settings.network.torrentPeerIdPrefixDescription)}
+                  placeholder="-FL-1-3-1-"
+                  maxLength={20}
+                  onCommit={settings.setTorrentPeerIdPrefix}
+                  onError={showTorrentNetworkInputError}
+                />
+                <TorrentNetworkTextInput
+                  field="torrentPeerAgent"
+                  value={settings.torrentPeerAgent}
+                  label={t($ => $.settings.network.torrentPeerAgent)}
+                  description={t($ => $.settings.network.torrentPeerAgentDescription)}
+                  placeholder="Firelink/1.3.1"
+                  maxLength={128}
+                  onCommit={settings.setTorrentPeerAgent}
+                  onError={showTorrentNetworkInputError}
+                />
                 <div className="mac-settings-row settings-network-row">
                   <div className="settings-row-label">
                     <span>{t($ => $.settings.network.torrentSeparateSeedSlots)}</span>
@@ -1639,20 +1700,16 @@ runEngineChecks(false);
                     aria-label={t($ => $.settings.network.torrentMaxOpenFiles)}
                   />
                 </div>
-                <div className="mac-settings-row settings-network-row">
-                  <div className="settings-row-label">
-                    <span>{t($ => $.settings.network.aria2DiskCache)}</span>
-                    <small>{t($ => $.settings.network.aria2DiskCacheDescription)}</small>
-                  </div>
-                  <input
-                    type="text"
-                    value={settings.aria2DiskCache}
-                    onChange={(event) => settings.setAria2DiskCache(event.target.value)}
-                    placeholder="16M"
-                    className="app-control settings-network-input text-center"
-                    aria-label={t($ => $.settings.network.aria2DiskCache)}
-                  />
-                </div>
+                <TorrentNetworkTextInput
+                  field="aria2DiskCache"
+                  value={settings.aria2DiskCache}
+                  label={t($ => $.settings.network.aria2DiskCache)}
+                  description={t($ => $.settings.network.aria2DiskCacheDescription)}
+                  placeholder="16M"
+                  onCommit={settings.setAria2DiskCache}
+                  onError={showTorrentNetworkInputError}
+                  className="app-control settings-network-input text-center"
+                />
                 <div className="mac-settings-row settings-network-row">
                   <div className="settings-row-label">
                     <span>{t($ => $.settings.network.torrentOverallUploadLimit)}</span>

src/i18n/catalogs/en.ts

@@ -1009,6 +1009,7 @@ const common = {
       aria2DiskCache: 'Aria2 disk cache',
       aria2DiskCacheDescription: 'Cache size for Aria2, using 0 or a positive value such as 16M. Accepts K/M values up to 1024M and applies after restart.',
       torrentMaxOpenFilesUpdateFailed: 'Could not apply the Torrent open-file limit: {{detail}}',
+      torrentNetworkInputInvalid: 'Could not apply this Torrent network setting: {{detail}}',
       torrentOverallUploadLimit: 'Overall Aria2 upload limit',
       torrentOverallUploadLimitDescription: 'Caps combined Aria2 upload traffic, primarily active Torrent seeding in Firelink. Leave blank for unlimited; the value is applied live and restored when Firelink restarts.',
       torrentOverallUploadLimitInvalid: 'Enter a valid upload limit, such as 512K or 2M.',

src/i18n/catalogs/fa.ts

@@ -1009,6 +1009,7 @@ const fa = {
       aria2DiskCache: 'کش دیسک Aria2',
       aria2DiskCacheDescription: 'اندازهٔ کش Aria2؛ صفر یا مقداری مانند 16M وارد کنید. مقادیر K/M تا 1024M پذیرفته می‌شوند و پس از راه‌اندازی مجدد اعمال می‌شوند.',
       torrentMaxOpenFilesUpdateFailed: 'اعمال محدودیت فایل‌های باز تورنت ممکن نشد: {{detail}}',
+      torrentNetworkInputInvalid: 'اعمال این تنظیم شبکه تورنت ممکن نیست: {{detail}}',
       torrentOverallUploadLimit: 'محدودیت کلی آپلود Aria2',
       torrentOverallUploadLimitDescription: 'سرعت کلی آپلود Aria2 را محدود می‌کند؛ در Firelink این مقدار عمدتاً برای سیدینگ تورنت‌هاست. برای نامحدود بودن خالی بگذارید؛ مقدار جدید زنده اعمال می‌شود و پس از راه‌اندازی مجدد Firelink برمی‌گردد.',
       torrentOverallUploadLimitInvalid: 'یک محدودیت معتبر مثل 512K یا 2M برای آپلود وارد کنید.',

src/i18n/catalogs/he.ts

@@ -1009,6 +1009,7 @@ const he = {
       aria2DiskCache: 'מטמון דיסק של Aria2',
       aria2DiskCacheDescription: 'גודל מטמון Aria2: 0 או ערך כמו 16M. ערכי K/M עד 1024M מתקבלים; חל לאחר הפעלה מחדש.',
       torrentMaxOpenFilesUpdateFailed: 'לא ניתן להחיל את מגבלת הקבצים הפתוחים של Torrent: {{detail}}',
+      torrentNetworkInputInvalid: 'לא ניתן להחיל את הגדרת רשת הטורנט: {{detail}}',
       torrentOverallUploadLimit: 'מגבלת העלאה כוללת של Aria2',
       torrentOverallUploadLimitDescription: 'מגבילה את מהירות ההעלאה המשולבת של Aria2, בעיקר עבור העלאת טורנטים פעילים ב-Firelink. השאר ריק ללא הגבלה; הערך מוחל מיד ומשוחזר לאחר הפעלה מחדש של Firelink.',
       torrentOverallUploadLimitInvalid: 'הזן מגבלת העלאה תקפה, למשל 512K או 2M.',

src/i18n/catalogs/ru.ts

@@ -1009,6 +1009,7 @@ const ru = {
       aria2DiskCache: 'Дисковый кэш Aria2',
       aria2DiskCacheDescription: 'Размер кэша Aria2: 0 или значение вроде 16M. Допустимы K/M до 1024M; применяется после перезапуска.',
       torrentMaxOpenFilesUpdateFailed: 'Не удалось применить лимит открытых файлов Torrent: {{detail}}',
+      torrentNetworkInputInvalid: 'Не удалось применить сетевую настройку Torrent: {{detail}}',
       torrentOverallUploadLimit: 'Общий лимит отдачи Aria2',
       torrentOverallUploadLimitDescription: 'Ограничивает суммарную скорость отдачи Aria2; в Firelink это в основном раздача активных торрентов. Оставьте поле пустым для снятия ограничения; значение применяется сразу и восстанавливается после перезапуска Firelink.',
       torrentOverallUploadLimitInvalid: 'Введите корректный лимит отдачи, например 512K или 2M.',

src/i18n/catalogs/uk.ts

@@ -1009,6 +1009,7 @@ const uk = {
       aria2DiskCache: 'Дисковий кеш Aria2',
       aria2DiskCacheDescription: 'Розмір кешу Aria2: 0 або значення на кшталт 16M. Допустимі K/M до 1024M; застосовується після перезапуску.',
       torrentMaxOpenFilesUpdateFailed: 'Не вдалося застосувати обмеження відкритих файлів Torrent: {{detail}}',
+      torrentNetworkInputInvalid: 'Не вдалося застосувати мережеве налаштування Torrent: {{detail}}',
       torrentOverallUploadLimit: 'Загальне обмеження віддачі Aria2',
       torrentOverallUploadLimitDescription: 'Обмежує сумарну швидкість віддачі Aria2; у Firelink це переважно роздача активних торрентів. Залиште поле порожнім без обмеження; значення застосовується одразу й відновлюється після перезапуску Firelink.',
       torrentOverallUploadLimitInvalid: 'Введіть коректне обмеження віддачі, наприклад 512K або 2M.',

src/i18n/catalogs/zh-CN.ts

@@ -1009,6 +1009,7 @@ const zhCN = {
       aria2DiskCache: 'Aria2 磁盘缓存',
       aria2DiskCacheDescription: 'Aria2 缓存大小：0 或类似 16M 的值。接受最大 1024M 的 K/M 值，重启后生效。',
       torrentMaxOpenFilesUpdateFailed: '无法应用 Torrent 打开文件数限制：{{detail}}',
+      torrentNetworkInputInvalid: '无法应用此 Torrent 网络设置：{{detail}}',
       torrentOverallUploadLimit: 'Aria2 总上传限制',
       torrentOverallUploadLimitDescription: '限制 Aria2 的总上传速度，在 Firelink 中主要用于活动 Torrent 做种。留空表示不限速；新值会立即应用，并在 Firelink 重启后恢复。',
       torrentOverallUploadLimitInvalid: '请输入有效的上传限制，例如 512K 或 2M。',

src/ipc.ts

@@ -144,6 +144,10 @@ type CommandMap = {
   get_supported_media_domains: { args: undefined; result: string[] };
   db_save_settings: { args: { data: string }; result: void };
   db_load_settings: { args: undefined; result: string | null };
+  canonicalize_torrent_network_setting: {
+    args: { field: string; value: string };
+    result: string;
+  };
   db_get_all_downloads: { args: undefined; result: string[] };
   db_replace_downloads: { args: { data: string }; result: void };
   db_commit_download_state: {

src/store/useSettingsStore.test.ts

@@ -133,6 +133,33 @@ describe('Torrent peer discovery preferences', () => {
     });
   });
 
+  it('clears an IPv6 bind address when IPv6 transport is disabled', () => {
+    useSettingsStore.setState({
+      torrentIpv6Enabled: true,
+      torrentBindAddress: '2001:db8::10'
+    });
+
+    useSettingsStore.getState().setTorrentIpv6Enabled(false);
+
+    expect(useSettingsStore.getState()).toMatchObject({
+      torrentIpv6Enabled: false,
+      torrentBindAddress: ''
+    });
+  });
+
+  it('rejects an IPv6 bind address entered after IPv6 transport is disabled', () => {
+    useSettingsStore.setState({
+      torrentIpv6Enabled: false,
+      torrentBindAddress: ''
+    });
+
+    expect(useSettingsStore.getState().setTorrentBindAddress('2001:db8::10')).toBe(false);
+    expect(useSettingsStore.getState().torrentBindAddress).toBe('');
+
+    expect(useSettingsStore.getState().setTorrentBindAddress('192.0.2.10')).toBe(true);
+    expect(useSettingsStore.getState().torrentBindAddress).toBe('192.0.2.10');
+  });
+
   it('matches Aria2 defaults and persists explicit changes', async () => {
     expect(useSettingsStore.getState().torrentEnableDht).toBe(true);
     expect(useSettingsStore.getState().torrentEnableDht6).toBe(false);

src/store/useSettingsStore.ts

@@ -364,7 +364,7 @@ export interface SettingsState {
   setTorrentLpdInterface: (value: string) => void;
   setTorrentPeerIdPrefix: (value: string) => void;
   setTorrentPeerAgent: (value: string) => void;
-  setTorrentBindAddress: (value: string) => void;
+  setTorrentBindAddress: (value: string) => boolean;
   setAria2DiskCache: (value: string) => void;
   setCustomUserAgent: (userAgent: string) => void;
   setAskWhereToSaveEachFile: (ask: boolean) => void;
@@ -612,7 +612,17 @@ export const useSettingsStore = create<SettingsState>()(
       setTorrentLpdInterface: (torrentLpdInterface) => set({ torrentLpdInterface }),
       setTorrentPeerIdPrefix: (torrentPeerIdPrefix) => set({ torrentPeerIdPrefix }),
       setTorrentPeerAgent: (torrentPeerAgent) => set({ torrentPeerAgent }),
-      setTorrentBindAddress: (torrentBindAddress) => set({ torrentBindAddress }),
+      setTorrentBindAddress: (torrentBindAddress) => {
+        let accepted = true;
+        set(state => {
+          if (!state.torrentIpv6Enabled && torrentBindAddress.includes(':')) {
+            accepted = false;
+            return state;
+          }
+          return { torrentBindAddress };
+        });
+        return accepted;
+      },
       setAria2DiskCache: (aria2DiskCache) => set({ aria2DiskCache }),
       setTorrentMaxOpenFiles: (value) => {
         const normalized = normalizeTorrentMaxOpenFiles(value);
@@ -643,7 +653,15 @@ export const useSettingsStore = create<SettingsState>()(
           ? value
           : DEFAULT_TORRENT_MAX_CONCURRENT_SEEDS
       }),
-      setTorrentIpv6Enabled: (torrentIpv6Enabled) => set({ torrentIpv6Enabled }),
+      setTorrentIpv6Enabled: (torrentIpv6Enabled) => set(state => ({
+        torrentIpv6Enabled,
+        // An IPv6 bind address is invalid once IPv6 transport is disabled.
+        // Clear it as part of the same state transition so the next durable
+        // settings save cannot fail on a cross-field contradiction.
+        ...(torrentIpv6Enabled || !state.torrentBindAddress.includes(':')
+          ? {}
+          : { torrentBindAddress: '' })
+      })),
       setCustomUserAgent: (customUserAgent) => set({ customUserAgent }),
       setAskWhereToSaveEachFile: (askWhereToSaveEachFile) => set({ askWhereToSaveEachFile }),
       setPreventsSleepWhileDownloading: (preventsSleepWhileDownloading) => {

src/utils/downloads.ts

@@ -81,7 +81,8 @@ export const MIN_TORRENT_MAX_OPEN_FILES = 1;
 export const MAX_TORRENT_MAX_OPEN_FILES = 4096;
 export const DEFAULT_TORRENT_DHT_MESSAGE_TIMEOUT = 10;
 export const MIN_TORRENT_DHT_MESSAGE_TIMEOUT = 1;
-export const MAX_TORRENT_DHT_MESSAGE_TIMEOUT = 600;
+// Aria2 1.37.0 accepts DHT message timeouts only from 1 through 60 seconds.
+export const MAX_TORRENT_DHT_MESSAGE_TIMEOUT = 60;
 export const DEFAULT_TORRENT_MAX_CONCURRENT_SEEDS = 2;
 export const MIN_TORRENT_MAX_CONCURRENT_SEEDS = 1;
 export const MAX_TORRENT_MAX_CONCURRENT_SEEDS = 64;

src/utils/torrentNetworkInput.test.ts

@@ -0,0 +1,16 @@
+import { describe, expect, it } from 'vitest';
+import { shouldApplyTorrentNetworkInputResult } from './torrentNetworkInput';
+
+describe('Torrent network input request fencing', () => {
+  it('rejects a response from an older request', () => {
+    expect(shouldApplyTorrentNetworkInputResult(1, 2, 4, 4)).toBe(false);
+  });
+
+  it('rejects a response after the user edits the draft', () => {
+    expect(shouldApplyTorrentNetworkInputResult(2, 2, 3, 4)).toBe(false);
+  });
+
+  it('accepts only the current request for the current draft', () => {
+    expect(shouldApplyTorrentNetworkInputResult(3, 3, 5, 5)).toBe(true);
+  });
+});

src/utils/torrentNetworkInput.ts

@@ -0,0 +1,6 @@
+export const shouldApplyTorrentNetworkInputResult = (
+  requestId: number,
+  currentRequestId: number,
+  editRequestId: number,
+  currentEditId: number
+): boolean => requestId === currentRequestId && editRequestId === currentEditId;