80 lines
2.9 KiB
Go
80 lines
2.9 KiB
Go
// Copyright 2018 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 host
|
|
|
|
import (
|
|
"fmt"
|
|
"syscall"
|
|
|
|
"gvisor.dev/gvisor/pkg/sentry/context"
|
|
"gvisor.dev/gvisor/pkg/sentry/device"
|
|
"gvisor.dev/gvisor/pkg/sentry/fs"
|
|
)
|
|
|
|
// beforeSave is invoked by stateify.
|
|
func (i *inodeFileState) beforeSave() {
|
|
if !i.queue.IsEmpty() {
|
|
panic("event queue must be empty")
|
|
}
|
|
if !i.descriptor.donated && i.sattr.Type == fs.RegularFile {
|
|
uattr, err := i.unstableAttr(context.Background())
|
|
if err != nil {
|
|
panic(fs.ErrSaveRejection{fmt.Errorf("failed to get unstable atttribute of %s: %v", i.mops.inodeMappings[i.sattr.InodeID], err)})
|
|
}
|
|
i.savedUAttr = &uattr
|
|
}
|
|
}
|
|
|
|
// afterLoad is invoked by stateify.
|
|
func (i *inodeFileState) afterLoad() {
|
|
// Initialize the descriptor value.
|
|
if err := i.descriptor.initAfterLoad(i.mops, i.sattr.InodeID, &i.queue); err != nil {
|
|
panic(fmt.Sprintf("failed to load value of descriptor: %v", err))
|
|
}
|
|
|
|
// Remap the inode number.
|
|
var s syscall.Stat_t
|
|
if err := syscall.Fstat(i.FD(), &s); err != nil {
|
|
panic(fs.ErrCorruption{fmt.Errorf("failed to get metadata for fd %d: %v", i.FD(), err)})
|
|
}
|
|
key := device.MultiDeviceKey{
|
|
Device: s.Dev,
|
|
Inode: s.Ino,
|
|
}
|
|
if !hostFileDevice.Load(key, i.sattr.InodeID) {
|
|
// This means there was a conflict at s.Dev and s.Ino with
|
|
// another inode mapping: two files that were unique on the
|
|
// saved filesystem are no longer unique on this filesystem.
|
|
// Since this violates the contract that filesystems cannot
|
|
// change across save and restore, error out.
|
|
panic(fs.ErrCorruption{fmt.Errorf("host %s conflict in host device mappings: %s", key, hostFileDevice)})
|
|
}
|
|
|
|
if !i.descriptor.donated && i.sattr.Type == fs.RegularFile {
|
|
env, ok := fs.CurrentRestoreEnvironment()
|
|
if !ok {
|
|
panic("missing restore environment")
|
|
}
|
|
uattr := unstableAttr(i.mops, &s)
|
|
if env.ValidateFileSize && uattr.Size != i.savedUAttr.Size {
|
|
panic(fs.ErrCorruption{fmt.Errorf("file size has changed for %s: previously %d, now %d", i.mops.inodeMappings[i.sattr.InodeID], i.savedUAttr.Size, uattr.Size)})
|
|
}
|
|
if env.ValidateFileTimestamp && uattr.ModificationTime != i.savedUAttr.ModificationTime {
|
|
panic(fs.ErrCorruption{fmt.Errorf("file modification time has changed for %s: previously %v, now %v", i.mops.inodeMappings[i.sattr.InodeID], i.savedUAttr.ModificationTime, uattr.ModificationTime)})
|
|
}
|
|
i.savedUAttr = nil
|
|
}
|
|
}
|