Implement stubs for msgget(2) and msgctl(IPC_RMID).

Add support for msgget, and msgctl(IPC_RMID), and enable msgqueue
syscall tests.

Updates #135

5 files changed, 71 insertions, 17 deletions

diff --git a/pkg/sentry/kernel/msgqueue/msgqueue.go b/pkg/sentry/kernel/msgqueue/msgqueue.go
index 5f7f35cd3..3ce926950 100644
--- a/pkg/sentry/kernel/msgqueue/msgqueue.go
+++ b/pkg/sentry/kernel/msgqueue/msgqueue.go
@@ -213,3 +213,8 @@ func (q *Queue) Destroy() {
 	q.senders.Notify(waiter.EventOut)
 	q.receivers.Notify(waiter.EventIn)
 }
+
+// ID returns queue's ID.
+func (q *Queue) ID() ipc.ID {
+	return q.obj.ID
+}
diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD
index 7941b2be9..ccccce6a9 100644
--- a/pkg/sentry/syscalls/linux/BUILD
+++ b/pkg/sentry/syscalls/linux/BUILD
@@ -25,6 +25,7 @@ go_library(
         "sys_mempolicy.go",
         "sys_mmap.go",
         "sys_mount.go",
+        "sys_msgqueue.go",
         "sys_pipe.go",
         "sys_poll.go",
         "sys_prctl.go",
diff --git a/pkg/sentry/syscalls/linux/linux64.go b/pkg/sentry/syscalls/linux/linux64.go
index f1cb5a2c8..6f44d767b 100644
--- a/pkg/sentry/syscalls/linux/linux64.go
+++ b/pkg/sentry/syscalls/linux/linux64.go
@@ -121,10 +121,10 @@ var AMD64 = &kernel.SyscallTable{
 		65:  syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil),
 		66:  syscalls.Supported("semctl", Semctl),
 		67:  syscalls.Supported("shmdt", Shmdt),
-		68:  syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
-		69:  syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
-		70:  syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
-		71:  syscalls.ErrorWithEvent("msgctl", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
+		68:  syscalls.Supported("msgget", Msgget),
+		69:  syscalls.ErrorWithEvent("msgsnd", linuxerr.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
+		70:  syscalls.ErrorWithEvent("msgrcv", linuxerr.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
+		71:  syscalls.PartiallySupported("msgctl", Msgctl, "Only supports IPC_RMID option.", []string{"gvisor.dev/issue/135"}),
 		72:  syscalls.PartiallySupported("fcntl", Fcntl, "Not all options are supported.", nil),
 		73:  syscalls.PartiallySupported("flock", Flock, "Locks are held within the sandbox only.", nil),
 		74:  syscalls.PartiallySupported("fsync", Fsync, "Full data flush is not guaranteed at this time.", nil),
@@ -616,10 +616,10 @@ var ARM64 = &kernel.SyscallTable{
 		183: syscalls.ErrorWithEvent("mq_timedreceive", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921)
 		184: syscalls.ErrorWithEvent("mq_notify", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}),       // TODO(b/29354921)
 		185: syscalls.ErrorWithEvent("mq_getsetattr", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}),   // TODO(b/29354921)
-		186: syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}),          // TODO(b/29354921)
-		187: syscalls.ErrorWithEvent("msgctl", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}),          // TODO(b/29354921)
-		188: syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}),          // TODO(b/29354921)
-		189: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}),          // TODO(b/29354921)
+		186: syscalls.Supported("msgget", Msgget),
+		187: syscalls.PartiallySupported("msgctl", Msgctl, "Only supports IPC_RMID option.", []string{"gvisor.dev/issue/135"}),
+		188: syscalls.ErrorWithEvent("msgrcv", linuxerr.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
+		189: syscalls.ErrorWithEvent("msgsnd", linuxerr.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921)
 		190: syscalls.Supported("semget", Semget),
 		191: syscalls.Supported("semctl", Semctl),
 		192: syscalls.Supported("semtimedop", Semtimedop),
diff --git a/pkg/sentry/syscalls/linux/sys_msgqueue.go b/pkg/sentry/syscalls/linux/sys_msgqueue.go
new file mode 100644
index 000000000..3476e218d
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_msgqueue.go
@@ -0,0 +1,57 @@
+// 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 linux
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/errors/linuxerr"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/ipc"
+)
+
+// Msgget implements msgget(2).
+func Msgget(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+	key := ipc.Key(args[0].Int())
+	flag := args[1].Int()
+
+	private := key == linux.IPC_PRIVATE
+	create := flag&linux.IPC_CREAT == linux.IPC_CREAT
+	exclusive := flag&linux.IPC_EXCL == linux.IPC_EXCL
+	mode := linux.FileMode(flag & 0777)
+
+	r := t.IPCNamespace().MsgqueueRegistry()
+	queue, err := r.FindOrCreate(t, key, mode, private, create, exclusive)
+	if err != nil {
+		return 0, nil, err
+	}
+	return uintptr(queue.ID()), nil, nil
+}
+
+// Msgctl implements msgctl(2).
+func Msgctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+	id := ipc.ID(args[0].Int())
+	cmd := args[1].Int()
+
+	creds := auth.CredentialsFromContext(t)
+
+	switch cmd {
+	case linux.IPC_RMID:
+		return 0, nil, t.IPCNamespace().MsgqueueRegistry().Remove(id, creds)
+	default:
+		return 0, nil, linuxerr.EINVAL
+	}
+}
diff --git a/test/syscalls/linux/msgqueue.cc b/test/syscalls/linux/msgqueue.cc
index ba61bba34..2409de7e8 100644
--- a/test/syscalls/linux/msgqueue.cc
+++ b/test/syscalls/linux/msgqueue.cc
@@ -48,9 +48,6 @@ class Queue {
 
 // Test simple creation and retrieval for msgget(2).
 TEST(MsgqueueTest, MsgGet) {
-  // Don't run test until syscall is implemented.
-  GTEST_SKIP();
-
   const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile());
   const key_t key = ftok(keyfile.path().c_str(), 1);
   ASSERT_THAT(key, SyscallSucceeds());
@@ -62,9 +59,6 @@ TEST(MsgqueueTest, MsgGet) {
 
 // Test simple failure scenarios for msgget(2).
 TEST(MsgqueueTest, MsgGetFail) {
-  // Don't run test until syscall is implemented.
-  GTEST_SKIP();
-
   const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile());
   const key_t key = ftok(keyfile.path().c_str(), 1);
   ASSERT_THAT(key, SyscallSucceeds());
@@ -79,9 +73,6 @@ TEST(MsgqueueTest, MsgGetFail) {
 
 // Test using msgget(2) with IPC_PRIVATE option.
 TEST(MsgqueueTest, MsgGetIpcPrivate) {
-  // Don't run test until syscall is implemented.
-  GTEST_SKIP();
-
   Queue queue1(msgget(IPC_PRIVATE, 0));
   ASSERT_THAT(queue1.get(), SyscallSucceeds());