From e8a158e4f5096e5200dc47c8d5d5148770ace234 Mon Sep 17 00:00:00 2001
From: zengLingbiao <zeng.lingbiao@xydigit.com>
Date: Sun, 2 Aug 2026 07:25:32 +0800
Subject: [PATCH] fix(signal): cancel unread body when declared archive length
 exceeds cap (#117665)

---
 .../signal/src/install-signal-cli.test.ts     | 19 +++++++++++++++++++
 extensions/signal/src/install-signal-cli.ts   |  1 +
 2 files changed, 20 insertions(+)

diff --git a/extensions/signal/src/install-signal-cli.test.ts b/extensions/signal/src/install-signal-cli.test.ts
index 5521f84f2725..00a2292eacd7 100644
--- a/extensions/signal/src/install-signal-cli.test.ts
+++ b/extensions/signal/src/install-signal-cli.test.ts
@@ -291,6 +291,25 @@ describe("downloadToFile", () => {
     expect(cancel).toHaveBeenCalledOnce();
   });
 
+  it("cancels the response body when the declared length exceeds the download cap", async () => {
+    const response = new Response("archive", {
+      status: 200,
+      headers: { "content-length": "12" },
+    });
+    const cancel = vi.spyOn(response.body!, "cancel").mockRejectedValueOnce(new Error("closed"));
+    fetchWithSsrFGuardMock.mockResolvedValue({ response, release: vi.fn() });
+
+    await withTempFile(async (filePath) => {
+      await expect(
+        downloadToFile("https://example.com/signal-cli.tgz", filePath, 5, 8),
+      ).rejects.toThrow("declared 12");
+
+      await expectPathMissing(filePath);
+    });
+
+    expect(cancel).toHaveBeenCalledOnce();
+  });
+
   it("downloads through the SSRF guard with an explicit timeout", async () => {
     const fetchResult = okDownloadResponse("archive");
     fetchWithSsrFGuardMock.mockResolvedValue(fetchResult);
diff --git a/extensions/signal/src/install-signal-cli.ts b/extensions/signal/src/install-signal-cli.ts
index 26ecf050a536..07fc5d7404a9 100644
--- a/extensions/signal/src/install-signal-cli.ts
+++ b/extensions/signal/src/install-signal-cli.ts
@@ -194,6 +194,7 @@ export async function downloadToFile(
         ? Number(trimmedLength)
         : Number.NaN;
       if (Number.isFinite(declaredLength) && declaredLength > maxBytes) {
+        await cancelUnusedResponseBody(response);
         throw new Error(
           `signal-cli archive exceeds the ${maxBytes}-byte download cap (declared ${declaredLength}).`,
         );