From 62db1fad2cb7d2249720e157aa79c84b7531a2e9 Mon Sep 17 00:00:00 2001 From: Jamie Liu Date: Thu, 12 Nov 2020 18:20:30 -0800 Subject: Fix misuses of kernel.Task as context.Context. kernel.Task can only be used as context.Context by that Task's task goroutine. This is violated in at least two places: - In any case where one thread accesses the /proc/[tid] of any other thread, passing the kernel.Task for [tid] as the context.Context is incorrect. - Task.rebuildTraceContext() may be called by Kernel.RebuildTraceContexts() outside the scope of any task goroutine. Fix these (as well as a data race on Task.traceContext discovered during the course of finding the latter). PiperOrigin-RevId: 342174404 --- pkg/sentry/kernel/task_log.go | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'pkg/sentry/kernel/task_log.go') diff --git a/pkg/sentry/kernel/task_log.go b/pkg/sentry/kernel/task_log.go index 7591eaace..c70e5e6ce 100644 --- a/pkg/sentry/kernel/task_log.go +++ b/pkg/sentry/kernel/task_log.go @@ -19,6 +19,7 @@ import ( "runtime/trace" "sort" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/usermem" ) @@ -215,7 +216,7 @@ func (t *Task) rebuildTraceContext(tid ThreadID) { // arbitrarily large (in general it won't be, especially for cases // where we're collecting a brief profile), so using the TID is a // reasonable compromise in this case. - t.traceContext, t.traceTask = trace.NewTask(t, fmt.Sprintf("tid:%d", tid)) + t.traceContext, t.traceTask = trace.NewTask(context.Background(), fmt.Sprintf("tid:%d", tid)) } // traceCloneEvent is called when a new task is spawned. -- cgit v1.2.3