6 files changed, 31 insertions, 7 deletions
diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD
index e91338da7..6ff3deb97 100644
--- a/pkg/sentry/kernel/BUILD
+++ b/pkg/sentry/kernel/BUILD
@@ -216,6 +216,7 @@ go_library(
     visibility = ["//:sandbox"],
     deps = [
         ":uncaught_signal_go_proto",
+        "//pkg/sentry/kernel/ipc",
         "//pkg/abi",
         "//pkg/abi/linux",
         "//pkg/abi/linux/errno",
diff --git a/pkg/sentry/kernel/context.go b/pkg/sentry/kernel/context.go
index a8596410f..7e11c6580 100644
--- a/pkg/sentry/kernel/context.go
+++ b/pkg/sentry/kernel/context.go
@@ -16,6 +16,7 @@ package kernel
 
 import (
 	"gvisor.dev/gvisor/pkg/context"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/ipc"
 )
 
 // contextID is the kernel package's type for context.Context.Value keys.
@@ -37,9 +38,6 @@ const (
 
 	// CtxUTSNamespace is a Context.Value key for a UTSNamespace.
 	CtxUTSNamespace
-
-	// CtxIPCNamespace is a Context.Value key for a IPCNamespace.
-	CtxIPCNamespace
 )
 
 // ContextCanTrace returns true if ctx is permitted to trace t, in the same sense
@@ -82,7 +80,7 @@ func UTSNamespaceFromContext(ctx context.Context) *UTSNamespace {
 // or nil if there is no such IPC namespace. It takes a reference on the
 // namespace.
 func IPCNamespaceFromContext(ctx context.Context) *IPCNamespace {
-	if v := ctx.Value(CtxIPCNamespace); v != nil {
+	if v := ctx.Value(ipc.CtxIPCNamespace); v != nil {
 		return v.(*IPCNamespace)
 	}
 	return nil
diff --git a/pkg/sentry/kernel/ipc/BUILD b/pkg/sentry/kernel/ipc/BUILD
index e42a94e15..a5cbb2b51 100644
--- a/pkg/sentry/kernel/ipc/BUILD
+++ b/pkg/sentry/kernel/ipc/BUILD
@@ -7,6 +7,7 @@ go_library(
     srcs = [
         "object.go",
         "registry.go",
+        "ns.go",
     ],
     visibility = ["//pkg/sentry:internal"],
     deps = [
diff --git a/pkg/sentry/kernel/ipc/ns.go b/pkg/sentry/kernel/ipc/ns.go
new file mode 100644
index 000000000..220c9eafb
--- /dev/null
+++ b/pkg/sentry/kernel/ipc/ns.go
@@ -0,0 +1,22 @@
+// Copyright 2021 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ipc
+
+type contextID int
+
+// CtxIPCNamespace is the context.Value key used to retreive an IPC namespace.
+// We define it here because it's needed in several packages, and is not
+// possible to use otherwise without causing a circular depenedency.
+const CtxIPCNamespace contextID = iota
diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index df5160b67..6ce3625d4 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -59,6 +59,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/epoll"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/futex"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/ipc"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/sched"
 	ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time"
 	"gvisor.dev/gvisor/pkg/sentry/limits"
@@ -861,7 +862,7 @@ func (ctx *createProcessContext) Value(key interface{}) interface{} {
 		return ctx.args.PIDNamespace
 	case CtxUTSNamespace:
 		return ctx.args.UTSNamespace
-	case CtxIPCNamespace:
+	case ipc.CtxIPCNamespace:
 		ipcns := ctx.args.IPCNamespace
 		ipcns.IncRef()
 		return ipcns
@@ -1689,7 +1690,7 @@ func (ctx supervisorContext) Value(key interface{}) interface{} {
 		return ctx.k.tasks.Root
 	case CtxUTSNamespace:
 		return ctx.k.rootUTSNamespace
-	case CtxIPCNamespace:
+	case ipc.CtxIPCNamespace:
 		ipcns := ctx.k.rootIPCNamespace
 		ipcns.IncRef()
 		return ipcns
diff --git a/pkg/sentry/kernel/task_context.go b/pkg/sentry/kernel/task_context.go
index c82d9e82b..cb9bcd7c0 100644
--- a/pkg/sentry/kernel/task_context.go
+++ b/pkg/sentry/kernel/task_context.go
@@ -23,6 +23,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/fs"
 	"gvisor.dev/gvisor/pkg/sentry/inet"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/ipc"
 	ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time"
 	"gvisor.dev/gvisor/pkg/sentry/limits"
 	"gvisor.dev/gvisor/pkg/sentry/pgalloc"
@@ -73,7 +74,7 @@ func (t *Task) contextValue(key interface{}, isTaskGoroutine bool) interface{} {
 			defer t.mu.Unlock()
 		}
 		return t.utsns
-	case CtxIPCNamespace:
+	case ipc.CtxIPCNamespace:
 		if !isTaskGoroutine {
 			t.mu.Lock()
 			defer t.mu.Unlock()