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Diffstat (limited to 'pkg/sentry/kernel/msgqueue/msgqueue.go')
-rw-r--r--pkg/sentry/kernel/msgqueue/msgqueue.go109
1 files changed, 109 insertions, 0 deletions
diff --git a/pkg/sentry/kernel/msgqueue/msgqueue.go b/pkg/sentry/kernel/msgqueue/msgqueue.go
index fab396d7c..7c459d076 100644
--- a/pkg/sentry/kernel/msgqueue/msgqueue.go
+++ b/pkg/sentry/kernel/msgqueue/msgqueue.go
@@ -206,6 +206,48 @@ func (r *Registry) FindByID(id ipc.ID) (*Queue, error) {
return mech.(*Queue), nil
}
+// IPCInfo reports global parameters for message queues. See msgctl(IPC_INFO).
+func (r *Registry) IPCInfo(ctx context.Context) *linux.MsgInfo {
+ return &linux.MsgInfo{
+ MsgPool: linux.MSGPOOL,
+ MsgMap: linux.MSGMAP,
+ MsgMax: linux.MSGMAX,
+ MsgMnb: linux.MSGMNB,
+ MsgMni: linux.MSGMNI,
+ MsgSsz: linux.MSGSSZ,
+ MsgTql: linux.MSGTQL,
+ MsgSeg: linux.MSGSEG,
+ }
+}
+
+// MsgInfo reports global parameters for message queues. See msgctl(MSG_INFO).
+func (r *Registry) MsgInfo(ctx context.Context) *linux.MsgInfo {
+ r.mu.Lock()
+ defer r.mu.Unlock()
+
+ var messages, bytes uint64
+ r.reg.ForAllObjects(
+ func(o ipc.Mechanism) {
+ q := o.(*Queue)
+ q.mu.Lock()
+ messages += q.messageCount
+ bytes += q.byteCount
+ q.mu.Unlock()
+ },
+ )
+
+ return &linux.MsgInfo{
+ MsgPool: int32(r.reg.ObjectCount()),
+ MsgMap: int32(messages),
+ MsgTql: int32(bytes),
+ MsgMax: linux.MSGMAX,
+ MsgMnb: linux.MSGMNB,
+ MsgMni: linux.MSGMNI,
+ MsgSsz: linux.MSGSSZ,
+ MsgSeg: linux.MSGSEG,
+ }
+}
+
// Send appends a message to the message queue, and returns an error if sending
// fails. See msgsnd(2).
func (q *Queue) Send(ctx context.Context, m Message, b Blocker, wait bool, pid int32) error {
@@ -465,6 +507,73 @@ func (q *Queue) msgAtIndex(mType int64) *Message {
return msg
}
+// Set modifies some values of the queue. See msgctl(IPC_SET).
+func (q *Queue) Set(ctx context.Context, ds *linux.MsqidDS) error {
+ q.mu.Lock()
+ defer q.mu.Unlock()
+
+ creds := auth.CredentialsFromContext(ctx)
+ if ds.MsgQbytes > maxQueueBytes && !creds.HasCapabilityIn(linux.CAP_SYS_RESOURCE, q.obj.UserNS) {
+ // "An attempt (IPC_SET) was made to increase msg_qbytes beyond the
+ // system parameter MSGMNB, but the caller is not privileged (Linux:
+ // does not have the CAP_SYS_RESOURCE capability)."
+ return linuxerr.EPERM
+ }
+
+ if err := q.obj.Set(ctx, &ds.MsgPerm); err != nil {
+ return err
+ }
+
+ q.maxBytes = ds.MsgQbytes
+ q.changeTime = ktime.NowFromContext(ctx)
+ return nil
+}
+
+// Stat returns a MsqidDS object filled with information about the queue. See
+// msgctl(IPC_STAT) and msgctl(MSG_STAT).
+func (q *Queue) Stat(ctx context.Context) (*linux.MsqidDS, error) {
+ return q.stat(ctx, fs.PermMask{Read: true})
+}
+
+// StatAny is similar to Queue.Stat, but doesn't require read permission. See
+// msgctl(MSG_STAT_ANY).
+func (q *Queue) StatAny(ctx context.Context) (*linux.MsqidDS, error) {
+ return q.stat(ctx, fs.PermMask{})
+}
+
+// stat returns a MsqidDS object filled with information about the queue. An
+// error is returned if the user doesn't have the specified permissions.
+func (q *Queue) stat(ctx context.Context, mask fs.PermMask) (*linux.MsqidDS, error) {
+ q.mu.Lock()
+ defer q.mu.Unlock()
+
+ creds := auth.CredentialsFromContext(ctx)
+ if !q.obj.CheckPermissions(creds, mask) {
+ // "The caller must have read permission on the message queue."
+ return nil, linuxerr.EACCES
+ }
+
+ return &linux.MsqidDS{
+ MsgPerm: linux.IPCPerm{
+ Key: uint32(q.obj.Key),
+ UID: uint32(creds.UserNamespace.MapFromKUID(q.obj.Owner.UID)),
+ GID: uint32(creds.UserNamespace.MapFromKGID(q.obj.Owner.GID)),
+ CUID: uint32(creds.UserNamespace.MapFromKUID(q.obj.Creator.UID)),
+ CGID: uint32(creds.UserNamespace.MapFromKGID(q.obj.Creator.GID)),
+ Mode: uint16(q.obj.Perms.LinuxMode()),
+ Seq: 0, // IPC sequences not supported.
+ },
+ MsgStime: q.sendTime.TimeT(),
+ MsgRtime: q.receiveTime.TimeT(),
+ MsgCtime: q.changeTime.TimeT(),
+ MsgCbytes: q.byteCount,
+ MsgQnum: q.messageCount,
+ MsgQbytes: q.maxBytes,
+ MsgLspid: q.sendPID,
+ MsgLrpid: q.receivePID,
+ }, nil
+}
+
// Lock implements ipc.Mechanism.Lock.
func (q *Queue) Lock() {
q.mu.Lock()