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https://github.com/netbirdio/gvisor.git
synced 2026-05-22 17:12:49 -07:00
Ayush RanjanandgVisor bot
9e66f710de
Our devtmpfs implementation uses the same tmpfs filesystem instance for all devtmpfs mounts in the sandbox. This would mean that devices mounted in a container are visible and accessible to all other containers in the sandbox. With GPU/TPU, the contents of devtmpfs can be different for different containers within the same sandbox. So it is important to not share the same devtmpfs contents. It is better to drop support for devtmpfs, than to implement it incorrectly. Instead, this change introduces a new dummy filesystem type named `dev`. This filesystem can not be mounted or listed by the application. This filesystem creates a new tmpfs instance on GetFilesystem() and populates it with all the device files. PiperOrigin-RevId: 578969556
46 lines
1.5 KiB
Go
46 lines
1.5 KiB
Go
// Copyright 2020 The gVisor Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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// Package memdev implements "mem" character devices, as implemented in Linux
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// by drivers/char/mem.c and drivers/char/random.c.
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package memdev
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import (
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"gvisor.dev/gvisor/pkg/abi/linux"
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"gvisor.dev/gvisor/pkg/sentry/vfs"
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)
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// Register registers all devices implemented by this package in vfsObj.
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func Register(vfsObj *vfs.VirtualFilesystem) error {
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for minor, spec := range map[uint32]struct {
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dev vfs.Device
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pathname string
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}{
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nullDevMinor: {nullDevice{}, "null"},
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zeroDevMinor: {zeroDevice{}, "zero"},
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fullDevMinor: {fullDevice{}, "full"},
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randomDevMinor: {randomDevice{}, "random"},
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urandomDevMinor: {randomDevice{}, "urandom"},
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} {
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if err := vfsObj.RegisterDevice(vfs.CharDevice, linux.MEM_MAJOR, minor, spec.dev, &vfs.RegisterDeviceOptions{
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GroupName: "mem",
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Pathname: spec.pathname,
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FilePerms: 0666,
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}); err != nil {
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return err
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}
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}
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return nil
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}
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