From 47b4bc1d4ea61e4b92b9d6a3bb36067e4b06490e Mon Sep 17 00:00:00 2001
From: Dotta <bippadotta@protonmail.com>
Date: Sat, 10 Oct 2026 13:59:39 -0500
Subject: [PATCH] fix: enforce file operation deadlines inside the remote
 process group

Apply GNU timeout after SSH admission deducts queue time. Verify a delayed remote-shaped Python write is killed independently of local SSH termination.

Co-Authored-By: Paperclip <noreply@paperclip.ing>
---
 .../modules/computers/adapters/boat.test.ts   | 30 ++++++++++++++++++-
 server/src/modules/computers/adapters/boat.ts | 16 ++++++++--
 2 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/server/src/modules/computers/adapters/boat.test.ts b/server/src/modules/computers/adapters/boat.test.ts
index 0f1ea78a08..1c1cd506c4 100644
--- a/server/src/modules/computers/adapters/boat.test.ts
+++ b/server/src/modules/computers/adapters/boat.test.ts
@@ -56,12 +56,40 @@ describe("Boat transport validation", () => {
     }));
     try {
       await backend.remote(scoped, { action: "read", path: "AGENTS.md" }, { deadlineMs: 1_120_000 });
-      expect(execute).toHaveBeenCalledWith(expect.objectContaining({ timeoutMs: 30_000 }));
+      expect(execute).toHaveBeenCalledWith(expect.objectContaining({
+        command: "timeout", args: expect.arrayContaining(["--signal=KILL", "30s", "python3"]), timeoutMs: 30_000,
+      }));
       clock = 1_120_000;
       await expect(backend.remote(scoped, { action: "write" }, { deadlineMs: clock })).rejects.toThrow("timed out");
       expect(execute).toHaveBeenCalledOnce();
     } finally { time.mockRestore(); sshFactory.mockReset(); }
   });
+  it("kills the remote Python group at the file deadline, independent of SSH closure", async () => {
+    const temp = realpathSync(mkdtempSync(join(tmpdir(), "boat-file-deadline-")));
+    const lateWrite = join(temp, "late-write");
+    let pid: number | undefined;
+    const scoped = { ...record, id: randomUUID(), providerId: `bx_${randomUUID()}` };
+    const execute = vi.fn(async (input: { command: string; args: string[]; stdin?: string }) => {
+      expect(input.command).toBe("timeout");
+      const args = [...input.args];
+      args[args.length - 1] = `import os,time;print(os.getpid(),flush=True);time.sleep(2);open(${JSON.stringify(lateWrite)},'w').write('late')`;
+      const result = spawnSync(input.command, args, { encoding: "utf8", input: input.stdin });
+      pid = Number(result.stdout.trim());
+      expect(pid).toBeGreaterThan(0);
+      return { exitCode: result.status, stdout: result.stdout, stderr: result.stderr, timedOut: false, signal: result.signal, pid: null, startedAt: "" };
+    });
+    sshFactory.mockReturnValue({ execute });
+    const backend = boatBackend(async () => "fixture", vi.fn(async () => json({ hostKey: "ssh-ed25519 AAAA", sshEndpoint: "fixture.invalid:2222" })));
+    try {
+      await expect(backend.remote(scoped, { action: "read" }, { deadlineMs: Date.now() + 300 })).rejects.toThrow("Computer operation failed");
+      await vi.waitFor(() => expect(() => process.kill(pid!, 0)).toThrow(), { timeout: 2000 });
+      expect(existsSync(lateWrite)).toBe(false);
+      expect(execute).toHaveBeenCalledOnce();
+    } finally {
+      sshFactory.mockReset();
+      rmSync(temp, { recursive: true, force: true });
+    }
+  });
   it("expires only the file waiter while shared SSH initialization remains usable", async () => {
     vi.useFakeTimers();
     const scoped = { ...record, id: randomUUID(), providerId: `bx_${randomUUID()}` };
diff --git a/server/src/modules/computers/adapters/boat.ts b/server/src/modules/computers/adapters/boat.ts
index 0cf1eeddb2..9f35158b06 100644
--- a/server/src/modules/computers/adapters/boat.ts
+++ b/server/src/modules/computers/adapters/boat.ts
@@ -340,7 +340,7 @@ export function boatBackend(
     }
     return pending;
   }
-  async function runner(record: ComputerRecord, options?: { control?: boolean }): Promise<CommandManagedRuntimeRunner> {
+  async function runner(record: ComputerRecord, options?: { control?: boolean; remoteTimeout?: boolean }): Promise<CommandManagedRuntimeRunner> {
     const raw = await rawRunner(record);
     let admission = transportAdmission.get(record.providerId);
     if (!admission) {
@@ -348,7 +348,17 @@ export function boatBackend(
       transportAdmission.set(record.providerId, admission);
     }
     const execute = admission;
-    return { ...raw, execute: (input) => execute(raw, input, options?.control === true) };
+    const bounded = options?.remoteTimeout ? {
+      ...raw,
+      execute: (input: CommandInput) => raw.execute({
+        ...input,
+        // Admission has already deducted queue time. Bound the remote process
+        // group as well as the local SSH child; socket closure is not stop proof.
+        command: "timeout",
+        args: ["--signal=KILL", `${input.timeoutMs! / 1000}s`, input.command, ...(input.args ?? [])],
+      }),
+    } : raw;
+    return { ...raw, execute: (input) => execute(bounded, input, options?.control === true) };
   }
   async function fileTransport(
     record: ComputerRecord,
@@ -356,7 +366,7 @@ export function boatBackend(
     options?: ComputerOperationOptions,
   ) {
     remaining(options, 120_000);
-    const pending = runner(record, { control });
+    const pending = runner(record, { control, remoteTimeout: options?.deadlineMs !== undefined });
     if (options?.deadlineMs === undefined) return pending;
     // Initialization is shared with unrelated owners. Expire this waiter only;
     // the cached promise retains its normal success/eviction behavior.