fix(runtime): bound run_command with ctx + 2-minute per-command timeout#63
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execRunCommand built its child process with shellexec.Command — no
context. cmd.CombinedOutput() then blocked until the child exited
regardless of parent cancellation. A small model that asked the runtime
to run a slow or runaway command (e.g. `go test ./... -run TestSlow`
against a test it just wrote with an infinite loop) would pin the
iteration goroutine for the full 5-minute outer budget — and on a
single-GPU Ollama config (concurrency: 1) every other story in the
wave queued behind it.
- Thread ctx from Execute → executeTool → execRunCommand. File ops
(read/write/edit) stay context-free; they're fast.
- Wrap with context.WithTimeout(ctx, runCommandTimeout). 2 minutes is a
comfortable ceiling for `go build ./...` / `go test ./...` on a
modest repo. A hung child now receives SIGKILL via Go's os/exec
context handling.
- On DeadlineExceeded, return actionable text to the model
("command timed out after 2m0s — split into smaller commands or
fix the slow path") instead of a generic exec error so the agent can
self-correct.
- Test files updated to pass context.Background() — the existing test
surface is unchanged in intent, just receives ctx.
- New test TestExecRunCommand_CancelledContextKillsCommand asserts a
pre-cancelled ctx surfaces as IsError without blocking.
Surfaced by the 2026-06-11 security audit (SEC-H1).
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Summary
execRunCommandbuilt its child process withshellexec.Command— no context.cmd.CombinedOutput()then blocked until the child exited regardless of parent cancellation. A small model that asked the runtime to run a slow or runaway command (e.g.go test ./... -run TestSlowagainst a test it just wrote with an infinite loop) would pin the iteration goroutine for the full 5-minute outer budget. On a single-GPU Ollama config (concurrency: 1) every other story in the wave queued behind it.Changes
ctxfromExecute→executeTool→execRunCommand. File ops (read/write/edit) stay context-free — they're fast.context.WithTimeout(ctx, runCommandTimeout). 2 minutes ceiling — comfortable forgo build ./.../go test ./...on a modest repo.os/execcontext handling.DeadlineExceeded, return actionable text to the model ("command timed out after 2m0s — split into smaller commands or fix the slow path") so the agent can self-correct.Test plan
TestExecRunCommand_CancelledContextKillsCommandasserts a pre-cancelledctxsurfaces asIsErrorwithout blocking.context.Background()for the existing surface.go build ./...,go vet ./...,go test ./... -count=1 -timeout 240sall green locally.Audit traceability
Security finding SEC-H1 (2026-06-11 sweep).