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-rw-r--r--pkg/sentry/fsimpl/mqfs/BUILD2
-rw-r--r--pkg/sentry/fsimpl/mqfs/mqfs.go4
-rw-r--r--pkg/sentry/fsimpl/mqfs/registry.go121
-rw-r--r--pkg/sentry/kernel/BUILD1
-rw-r--r--pkg/sentry/kernel/ipc_namespace.go25
-rw-r--r--pkg/sentry/kernel/mq/BUILD1
-rw-r--r--pkg/sentry/kernel/mq/mq.go51
7 files changed, 202 insertions, 3 deletions
diff --git a/pkg/sentry/fsimpl/mqfs/BUILD b/pkg/sentry/fsimpl/mqfs/BUILD
index 6b22ffabd..6892c6c25 100644
--- a/pkg/sentry/fsimpl/mqfs/BUILD
+++ b/pkg/sentry/fsimpl/mqfs/BUILD
@@ -20,6 +20,7 @@ go_library(
"mqfs.go",
"root.go",
"queue.go",
+ "registry.go",
"root_inode_refs.go",
],
visibility = ["//pkg/sentry:internal"],
@@ -32,6 +33,7 @@ go_library(
"//pkg/sentry/kernel/auth",
"//pkg/sentry/kernel/mq",
"//pkg/sentry/vfs",
+ "//pkg/sync",
"//pkg/usermem",
"//pkg/waiter",
],
diff --git a/pkg/sentry/fsimpl/mqfs/mqfs.go b/pkg/sentry/fsimpl/mqfs/mqfs.go
index 18bc66134..a92012deb 100644
--- a/pkg/sentry/fsimpl/mqfs/mqfs.go
+++ b/pkg/sentry/fsimpl/mqfs/mqfs.go
@@ -28,7 +28,7 @@ import (
)
const (
- fsName = "mqueue"
+ Name = "mqueue"
defaultMaxCachedDentries = uint64(1000)
)
@@ -39,7 +39,7 @@ type FilesystemType struct{}
// Name implements vfs.FilesystemType.Name.
func (FilesystemType) Name() string {
- return fsName
+ return Name
}
// Release implements vfs.FilesystemType.Release.
diff --git a/pkg/sentry/fsimpl/mqfs/registry.go b/pkg/sentry/fsimpl/mqfs/registry.go
new file mode 100644
index 000000000..3875b39ee
--- /dev/null
+++ b/pkg/sentry/fsimpl/mqfs/registry.go
@@ -0,0 +1,121 @@
+// 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 mqfs
+
+import (
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/context"
+ "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs"
+ "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+ "gvisor.dev/gvisor/pkg/sentry/kernel/mq"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+ "gvisor.dev/gvisor/pkg/sync"
+)
+
+// RegistryImpl implements mq.RegistryImpl. It implements the interface using
+// the message queue filesystem, and is provided to mq.Registry at
+// initialization.
+//
+// +stateify savable
+type RegistryImpl struct {
+ // mu protects all fields below.
+ mu sync.Mutex
+
+ // root is the root dentry of the mq filesystem. Its main usage is to
+ // retreive the root inode, which we use to add, remove, and lookup message
+ // queues.
+ //
+ // We hold a reference on root and release when the registry is destroyed.
+ root *kernfs.Dentry
+
+ // fs is the filesystem backing this registry, used mainly to initialize
+ // new inodes.
+ fs *filesystem
+
+ // mount is the mount point used for this filesystem.
+ mount *vfs.Mount
+}
+
+// NewRegistryImpl returns a new, initialized RegistryImpl, and takes a
+// reference on root.
+func NewRegistryImpl(root *kernfs.Dentry, fs *filesystem) *RegistryImpl {
+ root.IncRef()
+ return &RegistryImpl{
+ root: root,
+ fs: fs,
+ }
+}
+
+// Lookup implements mq.RegistryImpl.Lookup.
+func (r *RegistryImpl) Lookup(ctx context.Context, name string) *mq.Queue {
+ r.mu.Lock()
+ defer r.mu.Unlock()
+
+ inode, err := r.lookup(ctx, name)
+ if err != nil {
+ return nil
+ }
+ return inode.(*queueInode).queue
+}
+
+// New implements mq.RegistryImpl.New.
+func (r *RegistryImpl) New(ctx context.Context, name string, q *mq.Queue, perm linux.FileMode) (*vfs.FileDescription, error) {
+ r.mu.Lock()
+ defer r.mu.Unlock()
+
+ root := r.root.Inode().(*rootInode)
+ qInode := r.fs.newQueueInode(ctx, auth.CredentialsFromContext(ctx), q, perm).(*queueInode)
+ err := root.Insert(name, qInode)
+ if err != nil {
+ return nil, err
+ }
+
+ fd := &queueFD{queue: q}
+ err = fd.Init(r.mount, r.root, qInode.data, &qInode.locks, 0 /* flags */)
+ if err != nil {
+ return nil, err
+ }
+ return fd.VFSFileDescription(), nil
+}
+
+// Unlink implements mq.RegistryImpl.Unlink.
+func (r *RegistryImpl) Unlink(ctx context.Context, name string) error {
+ r.mu.Lock()
+ defer r.mu.Unlock()
+
+ root := r.root.Inode().(*rootInode)
+ inode, err := r.lookup(ctx, name)
+ if err != nil {
+ return err
+ }
+ return root.Unlink(ctx, name, inode)
+}
+
+// lookup retreives a kernfs.Inode using a name.
+//
+// Precondition: r.mu must be held.
+func (r *RegistryImpl) lookup(ctx context.Context, name string) (kernfs.Inode, error) {
+ inode := r.root.Inode().(*rootInode)
+ lookup, err := inode.Lookup(ctx, name)
+ if err != nil {
+ return nil, err
+ }
+ return lookup, nil
+}
+
+// Destroy implements mq.RegistryImpl.Destroy.
+func (r *RegistryImpl) Destroy(ctx context.Context) {
+ r.root.DecRef(ctx)
+}
diff --git a/pkg/sentry/kernel/BUILD b/pkg/sentry/kernel/BUILD
index c0f13bf52..e91338da7 100644
--- a/pkg/sentry/kernel/BUILD
+++ b/pkg/sentry/kernel/BUILD
@@ -257,6 +257,7 @@ go_library(
"//pkg/sentry/kernel/auth",
"//pkg/sentry/kernel/epoll",
"//pkg/sentry/kernel/futex",
+ "//pkg/sentry/kernel/mq",
"//pkg/sentry/kernel/msgqueue",
"//pkg/sentry/kernel/sched",
"//pkg/sentry/kernel/semaphore",
diff --git a/pkg/sentry/kernel/ipc_namespace.go b/pkg/sentry/kernel/ipc_namespace.go
index 0b101b1bb..aa9c3fb31 100644
--- a/pkg/sentry/kernel/ipc_namespace.go
+++ b/pkg/sentry/kernel/ipc_namespace.go
@@ -17,6 +17,7 @@ package kernel
import (
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+ "gvisor.dev/gvisor/pkg/sentry/kernel/mq"
"gvisor.dev/gvisor/pkg/sentry/kernel/msgqueue"
"gvisor.dev/gvisor/pkg/sentry/kernel/semaphore"
"gvisor.dev/gvisor/pkg/sentry/kernel/shm"
@@ -31,9 +32,17 @@ type IPCNamespace struct {
// User namespace which owns this IPC namespace. Immutable.
userNS *auth.UserNamespace
+ // System V utilities.
queues *msgqueue.Registry
semaphores *semaphore.Registry
shms *shm.Registry
+
+ // posixQueues is a POSIX message queue registry.
+ //
+ // posixQueues is somewhat equivelant to Linux's ipc_namespace.mq_mnt.
+ // Unlike SysV utilities, mq.Registry is not map-based, but is backed by
+ // a virtual filesystem.
+ posixQueues *mq.Registry
}
// NewIPCNamespace creates a new IPC namespace.
@@ -63,10 +72,26 @@ func (i *IPCNamespace) ShmRegistry() *shm.Registry {
return i.shms
}
+// SetPosixQueues sets value of posixQueues if the value is currently nil,
+// otherwise returns without doing anything.
+func (i *IPCNamespace) SetPosixQueues(r *mq.Registry) {
+ if i.posixQueues == nil {
+ i.posixQueues = r
+ }
+}
+
+// PosixQueues returns the posix message queue registry for this namespace.
+func (i *IPCNamespace) PosixQueues() *mq.Registry {
+ return i.posixQueues
+}
+
// DecRef implements refsvfs2.RefCounter.DecRef.
func (i *IPCNamespace) DecRef(ctx context.Context) {
i.IPCNamespaceRefs.DecRef(func() {
i.shms.Release(ctx)
+ if i.posixQueues != nil {
+ i.posixQueues.Destroy(ctx)
+ }
})
}
diff --git a/pkg/sentry/kernel/mq/BUILD b/pkg/sentry/kernel/mq/BUILD
index b4e17b582..7b00b8346 100644
--- a/pkg/sentry/kernel/mq/BUILD
+++ b/pkg/sentry/kernel/mq/BUILD
@@ -26,6 +26,7 @@ go_library(
"//pkg/abi/linux",
"//pkg/context",
"//pkg/sentry/fs",
+ "//pkg/sentry/vfs",
"//pkg/sync",
"//pkg/waiter",
],
diff --git a/pkg/sentry/kernel/mq/mq.go b/pkg/sentry/kernel/mq/mq.go
index 29a46e8a9..be46f78c8 100644
--- a/pkg/sentry/kernel/mq/mq.go
+++ b/pkg/sentry/kernel/mq/mq.go
@@ -22,6 +22,7 @@ import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/sentry/fs"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
"gvisor.dev/gvisor/pkg/sync"
"gvisor.dev/gvisor/pkg/waiter"
)
@@ -30,6 +31,54 @@ const (
maxPriority = linux.MQ_PRIO_MAX - 1 // Highest possible message priority.
)
+// Registry is a POSIX message queue registry.
+//
+// Unlike SysV utilities, Registry is not map-based. It uses a provided
+// RegistryImpl backed by a virtual filesystem to implement registry operations.
+//
+// +stateify savable
+type Registry struct {
+ // impl is an implementation of several message queue utilities needed by
+ // the registry. impl should be provided by mqfs.
+ impl RegistryImpl
+}
+
+// RegistryImpl defines utilities needed by a Registry to provide actual
+// registry implementation. It works mainly as an abstraction layer used by
+// Registry to avoid dealing directly with the filesystem. RegistryImpl should
+// be implemented by mqfs and provided to Registry at initialization.
+type RegistryImpl interface {
+ // Lookup returns the queue with the given name, nil if non exists.
+ Lookup(context.Context, string) *Queue
+
+ // New creates a new inode and file description using the given queue,
+ // inserts the inode into the filesystem tree with the given name, and
+ // returns the file description. An error is returned if creation fails, or
+ // if the name already exists.
+ New(context.Context, string, *Queue, linux.FileMode) (*vfs.FileDescription, error)
+
+ // Unlink removes the queue with given name from the registry, and returns
+ // an error if the name doesn't exist.
+ Unlink(context.Context, string) error
+
+ // Destroy destroys the registry.
+ Destroy(context.Context)
+}
+
+// NewRegistry returns a new, initialized message queue registry. NewRegistry
+// should be called when a new message queue filesystem is created, once per
+// IPCNamespace.
+func NewRegistry(impl RegistryImpl) *Registry {
+ return &Registry{
+ impl: impl,
+ }
+}
+
+// Destroy destroys the registry and releases all held references.
+func (r *Registry) Destroy(ctx context.Context) {
+ r.impl.Destroy(ctx)
+}
+
// Queue represents a POSIX message queue.
//
// +stateify savable
@@ -103,7 +152,7 @@ type Subscriber struct {
}
// Generate implements vfs.DynamicBytesSource.Generate. Queue is used as a
-// dynamic bytes source for mqfs's queueInode.
+// DynamicBytesSource for mqfs's queueInode.
func (q *Queue) Generate(ctx context.Context, buf *bytes.Buffer) error {
q.mu.Lock()
defer q.mu.Unlock()
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 20:52:54 +0000