summaryrefslogtreecommitdiffhomepage
path: root/pkg/sentry/fsimpl/host
diff options
context:
space:
mode:
Diffstat (limited to 'pkg/sentry/fsimpl/host')
-rw-r--r--pkg/sentry/fsimpl/host/BUILD79
-rw-r--r--pkg/sentry/fsimpl/host/connected_endpoint_refs.go132
-rw-r--r--pkg/sentry/fsimpl/host/host_state_autogen.go274
-rw-r--r--pkg/sentry/fsimpl/host/host_unsafe_state_autogen.go3
-rw-r--r--pkg/sentry/fsimpl/host/inode_refs.go132
5 files changed, 541 insertions, 79 deletions
diff --git a/pkg/sentry/fsimpl/host/BUILD b/pkg/sentry/fsimpl/host/BUILD
deleted file mode 100644
index 4ae9d6d5e..000000000
--- a/pkg/sentry/fsimpl/host/BUILD
+++ /dev/null
@@ -1,79 +0,0 @@
-load("//tools:defs.bzl", "go_library")
-load("//tools/go_generics:defs.bzl", "go_template_instance")
-
-licenses(["notice"])
-
-go_template_instance(
- name = "inode_refs",
- out = "inode_refs.go",
- package = "host",
- prefix = "inode",
- template = "//pkg/refsvfs2:refs_template",
- types = {
- "T": "inode",
- },
-)
-
-go_template_instance(
- name = "connected_endpoint_refs",
- out = "connected_endpoint_refs.go",
- package = "host",
- prefix = "ConnectedEndpoint",
- template = "//pkg/refsvfs2:refs_template",
- types = {
- "T": "ConnectedEndpoint",
- },
-)
-
-go_library(
- name = "host",
- srcs = [
- "connected_endpoint_refs.go",
- "control.go",
- "host.go",
- "inode_refs.go",
- "ioctl_unsafe.go",
- "save_restore.go",
- "socket.go",
- "socket_iovec.go",
- "socket_unsafe.go",
- "tty.go",
- "util.go",
- "util_unsafe.go",
- ],
- visibility = ["//pkg/sentry:internal"],
- deps = [
- "//pkg/abi/linux",
- "//pkg/context",
- "//pkg/fdnotifier",
- "//pkg/fspath",
- "//pkg/iovec",
- "//pkg/log",
- "//pkg/marshal/primitive",
- "//pkg/refs",
- "//pkg/refsvfs2",
- "//pkg/safemem",
- "//pkg/sentry/arch",
- "//pkg/sentry/fs/fsutil",
- "//pkg/sentry/fs/lock",
- "//pkg/sentry/fsimpl/kernfs",
- "//pkg/sentry/hostfd",
- "//pkg/sentry/kernel",
- "//pkg/sentry/kernel/auth",
- "//pkg/sentry/memmap",
- "//pkg/sentry/socket/control",
- "//pkg/sentry/socket/unix",
- "//pkg/sentry/socket/unix/transport",
- "//pkg/sentry/unimpl",
- "//pkg/sentry/uniqueid",
- "//pkg/sentry/vfs",
- "//pkg/sync",
- "//pkg/syserr",
- "//pkg/syserror",
- "//pkg/tcpip",
- "//pkg/unet",
- "//pkg/usermem",
- "//pkg/waiter",
- "@org_golang_x_sys//unix:go_default_library",
- ],
-)
diff --git a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
new file mode 100644
index 000000000..d784166ae
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
@@ -0,0 +1,132 @@
+package host
+
+import (
+ "fmt"
+ "sync/atomic"
+
+ "gvisor.dev/gvisor/pkg/refsvfs2"
+)
+
+// enableLogging indicates whether reference-related events should be logged (with
+// stack traces). This is false by default and should only be set to true for
+// debugging purposes, as it can generate an extremely large amount of output
+// and drastically degrade performance.
+const ConnectedEndpointenableLogging = false
+
+// obj is used to customize logging. Note that we use a pointer to T so that
+// we do not copy the entire object when passed as a format parameter.
+var ConnectedEndpointobj *ConnectedEndpoint
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// +stateify savable
+type ConnectedEndpointRefs struct {
+ // refCount is composed of two fields:
+ //
+ // [32-bit speculative references]:[32-bit real references]
+ //
+ // Speculative references are used for TryIncRef, to avoid a CompareAndSwap
+ // loop. See IncRef, DecRef and TryIncRef for details of how these fields are
+ // used.
+ refCount int64
+}
+
+// InitRefs initializes r with one reference and, if enabled, activates leak
+// checking.
+func (r *ConnectedEndpointRefs) InitRefs() {
+ atomic.StoreInt64(&r.refCount, 1)
+ refsvfs2.Register(r)
+}
+
+// RefType implements refsvfs2.CheckedObject.RefType.
+func (r *ConnectedEndpointRefs) RefType() string {
+ return fmt.Sprintf("%T", ConnectedEndpointobj)[1:]
+}
+
+// LeakMessage implements refsvfs2.CheckedObject.LeakMessage.
+func (r *ConnectedEndpointRefs) LeakMessage() string {
+ return fmt.Sprintf("[%s %p] reference count of %d instead of 0", r.RefType(), r, r.ReadRefs())
+}
+
+// LogRefs implements refsvfs2.CheckedObject.LogRefs.
+func (r *ConnectedEndpointRefs) LogRefs() bool {
+ return ConnectedEndpointenableLogging
+}
+
+// ReadRefs returns the current number of references. The returned count is
+// inherently racy and is unsafe to use without external synchronization.
+func (r *ConnectedEndpointRefs) ReadRefs() int64 {
+ return atomic.LoadInt64(&r.refCount)
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *ConnectedEndpointRefs) IncRef() {
+ v := atomic.AddInt64(&r.refCount, 1)
+ if ConnectedEndpointenableLogging {
+ refsvfs2.LogIncRef(r, v)
+ }
+ if v <= 1 {
+ panic(fmt.Sprintf("Incrementing non-positive count %p on %s", r, r.RefType()))
+ }
+}
+
+// TryIncRef implements refs.RefCounter.TryIncRef.
+//
+// To do this safely without a loop, a speculative reference is first acquired
+// on the object. This allows multiple concurrent TryIncRef calls to distinguish
+// other TryIncRef calls from genuine references held.
+//
+//go:nosplit
+func (r *ConnectedEndpointRefs) TryIncRef() bool {
+ const speculativeRef = 1 << 32
+ if v := atomic.AddInt64(&r.refCount, speculativeRef); int32(v) == 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ v := atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ if ConnectedEndpointenableLogging {
+ refsvfs2.LogTryIncRef(r, v)
+ }
+ return true
+}
+
+// DecRef implements refs.RefCounter.DecRef.
+//
+// Note that speculative references are counted here. Since they were added
+// prior to real references reaching zero, they will successfully convert to
+// real references. In other words, we see speculative references only in the
+// following case:
+//
+// A: TryIncRef [speculative increase => sees non-negative references]
+// B: DecRef [real decrease]
+// A: TryIncRef [transform speculative to real]
+//
+//go:nosplit
+func (r *ConnectedEndpointRefs) DecRef(destroy func()) {
+ v := atomic.AddInt64(&r.refCount, -1)
+ if ConnectedEndpointenableLogging {
+ refsvfs2.LogDecRef(r, v)
+ }
+ switch {
+ case v < 0:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %s", r, r.RefType()))
+
+ case v == 0:
+ refsvfs2.Unregister(r)
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
+
+func (r *ConnectedEndpointRefs) afterLoad() {
+ if r.ReadRefs() > 0 {
+ refsvfs2.Register(r)
+ }
+}
diff --git a/pkg/sentry/fsimpl/host/host_state_autogen.go b/pkg/sentry/fsimpl/host/host_state_autogen.go
new file mode 100644
index 000000000..705f8010a
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/host_state_autogen.go
@@ -0,0 +1,274 @@
+// automatically generated by stateify.
+
+package host
+
+import (
+ "gvisor.dev/gvisor/pkg/state"
+)
+
+func (r *ConnectedEndpointRefs) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.ConnectedEndpointRefs"
+}
+
+func (r *ConnectedEndpointRefs) StateFields() []string {
+ return []string{
+ "refCount",
+ }
+}
+
+func (r *ConnectedEndpointRefs) beforeSave() {}
+
+func (r *ConnectedEndpointRefs) StateSave(stateSinkObject state.Sink) {
+ r.beforeSave()
+ stateSinkObject.Save(0, &r.refCount)
+}
+
+func (r *ConnectedEndpointRefs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &r.refCount)
+ stateSourceObject.AfterLoad(r.afterLoad)
+}
+
+func (i *inode) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.inode"
+}
+
+func (i *inode) StateFields() []string {
+ return []string{
+ "InodeNoStatFS",
+ "InodeNotDirectory",
+ "InodeNotSymlink",
+ "CachedMappable",
+ "InodeTemporary",
+ "locks",
+ "inodeRefs",
+ "hostFD",
+ "ino",
+ "ftype",
+ "mayBlock",
+ "seekable",
+ "isTTY",
+ "savable",
+ "queue",
+ "haveBuf",
+ "buf",
+ }
+}
+
+func (i *inode) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.InodeNoStatFS)
+ stateSinkObject.Save(1, &i.InodeNotDirectory)
+ stateSinkObject.Save(2, &i.InodeNotSymlink)
+ stateSinkObject.Save(3, &i.CachedMappable)
+ stateSinkObject.Save(4, &i.InodeTemporary)
+ stateSinkObject.Save(5, &i.locks)
+ stateSinkObject.Save(6, &i.inodeRefs)
+ stateSinkObject.Save(7, &i.hostFD)
+ stateSinkObject.Save(8, &i.ino)
+ stateSinkObject.Save(9, &i.ftype)
+ stateSinkObject.Save(10, &i.mayBlock)
+ stateSinkObject.Save(11, &i.seekable)
+ stateSinkObject.Save(12, &i.isTTY)
+ stateSinkObject.Save(13, &i.savable)
+ stateSinkObject.Save(14, &i.queue)
+ stateSinkObject.Save(15, &i.haveBuf)
+ stateSinkObject.Save(16, &i.buf)
+}
+
+func (i *inode) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.InodeNoStatFS)
+ stateSourceObject.Load(1, &i.InodeNotDirectory)
+ stateSourceObject.Load(2, &i.InodeNotSymlink)
+ stateSourceObject.Load(3, &i.CachedMappable)
+ stateSourceObject.Load(4, &i.InodeTemporary)
+ stateSourceObject.Load(5, &i.locks)
+ stateSourceObject.Load(6, &i.inodeRefs)
+ stateSourceObject.Load(7, &i.hostFD)
+ stateSourceObject.Load(8, &i.ino)
+ stateSourceObject.Load(9, &i.ftype)
+ stateSourceObject.Load(10, &i.mayBlock)
+ stateSourceObject.Load(11, &i.seekable)
+ stateSourceObject.Load(12, &i.isTTY)
+ stateSourceObject.Load(13, &i.savable)
+ stateSourceObject.Load(14, &i.queue)
+ stateSourceObject.Load(15, &i.haveBuf)
+ stateSourceObject.Load(16, &i.buf)
+ stateSourceObject.AfterLoad(i.afterLoad)
+}
+
+func (f *filesystemType) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.filesystemType"
+}
+
+func (f *filesystemType) StateFields() []string {
+ return []string{}
+}
+
+func (f *filesystemType) beforeSave() {}
+
+func (f *filesystemType) StateSave(stateSinkObject state.Sink) {
+ f.beforeSave()
+}
+
+func (f *filesystemType) afterLoad() {}
+
+func (f *filesystemType) StateLoad(stateSourceObject state.Source) {
+}
+
+func (fs *filesystem) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.filesystem"
+}
+
+func (fs *filesystem) StateFields() []string {
+ return []string{
+ "Filesystem",
+ "devMinor",
+ }
+}
+
+func (fs *filesystem) beforeSave() {}
+
+func (fs *filesystem) StateSave(stateSinkObject state.Sink) {
+ fs.beforeSave()
+ stateSinkObject.Save(0, &fs.Filesystem)
+ stateSinkObject.Save(1, &fs.devMinor)
+}
+
+func (fs *filesystem) afterLoad() {}
+
+func (fs *filesystem) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &fs.Filesystem)
+ stateSourceObject.Load(1, &fs.devMinor)
+}
+
+func (f *fileDescription) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.fileDescription"
+}
+
+func (f *fileDescription) StateFields() []string {
+ return []string{
+ "vfsfd",
+ "FileDescriptionDefaultImpl",
+ "LockFD",
+ "inode",
+ "offset",
+ }
+}
+
+func (f *fileDescription) beforeSave() {}
+
+func (f *fileDescription) StateSave(stateSinkObject state.Sink) {
+ f.beforeSave()
+ stateSinkObject.Save(0, &f.vfsfd)
+ stateSinkObject.Save(1, &f.FileDescriptionDefaultImpl)
+ stateSinkObject.Save(2, &f.LockFD)
+ stateSinkObject.Save(3, &f.inode)
+ stateSinkObject.Save(4, &f.offset)
+}
+
+func (f *fileDescription) afterLoad() {}
+
+func (f *fileDescription) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &f.vfsfd)
+ stateSourceObject.Load(1, &f.FileDescriptionDefaultImpl)
+ stateSourceObject.Load(2, &f.LockFD)
+ stateSourceObject.Load(3, &f.inode)
+ stateSourceObject.Load(4, &f.offset)
+}
+
+func (r *inodeRefs) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.inodeRefs"
+}
+
+func (r *inodeRefs) StateFields() []string {
+ return []string{
+ "refCount",
+ }
+}
+
+func (r *inodeRefs) beforeSave() {}
+
+func (r *inodeRefs) StateSave(stateSinkObject state.Sink) {
+ r.beforeSave()
+ stateSinkObject.Save(0, &r.refCount)
+}
+
+func (r *inodeRefs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &r.refCount)
+ stateSourceObject.AfterLoad(r.afterLoad)
+}
+
+func (c *ConnectedEndpoint) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.ConnectedEndpoint"
+}
+
+func (c *ConnectedEndpoint) StateFields() []string {
+ return []string{
+ "ConnectedEndpointRefs",
+ "fd",
+ "addr",
+ "stype",
+ }
+}
+
+func (c *ConnectedEndpoint) beforeSave() {}
+
+func (c *ConnectedEndpoint) StateSave(stateSinkObject state.Sink) {
+ c.beforeSave()
+ stateSinkObject.Save(0, &c.ConnectedEndpointRefs)
+ stateSinkObject.Save(1, &c.fd)
+ stateSinkObject.Save(2, &c.addr)
+ stateSinkObject.Save(3, &c.stype)
+}
+
+func (c *ConnectedEndpoint) afterLoad() {}
+
+func (c *ConnectedEndpoint) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &c.ConnectedEndpointRefs)
+ stateSourceObject.Load(1, &c.fd)
+ stateSourceObject.Load(2, &c.addr)
+ stateSourceObject.Load(3, &c.stype)
+}
+
+func (t *TTYFileDescription) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.TTYFileDescription"
+}
+
+func (t *TTYFileDescription) StateFields() []string {
+ return []string{
+ "fileDescription",
+ "session",
+ "fgProcessGroup",
+ "termios",
+ }
+}
+
+func (t *TTYFileDescription) beforeSave() {}
+
+func (t *TTYFileDescription) StateSave(stateSinkObject state.Sink) {
+ t.beforeSave()
+ stateSinkObject.Save(0, &t.fileDescription)
+ stateSinkObject.Save(1, &t.session)
+ stateSinkObject.Save(2, &t.fgProcessGroup)
+ stateSinkObject.Save(3, &t.termios)
+}
+
+func (t *TTYFileDescription) afterLoad() {}
+
+func (t *TTYFileDescription) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &t.fileDescription)
+ stateSourceObject.Load(1, &t.session)
+ stateSourceObject.Load(2, &t.fgProcessGroup)
+ stateSourceObject.Load(3, &t.termios)
+}
+
+func init() {
+ state.Register((*ConnectedEndpointRefs)(nil))
+ state.Register((*inode)(nil))
+ state.Register((*filesystemType)(nil))
+ state.Register((*filesystem)(nil))
+ state.Register((*fileDescription)(nil))
+ state.Register((*inodeRefs)(nil))
+ state.Register((*ConnectedEndpoint)(nil))
+ state.Register((*TTYFileDescription)(nil))
+}
diff --git a/pkg/sentry/fsimpl/host/host_unsafe_state_autogen.go b/pkg/sentry/fsimpl/host/host_unsafe_state_autogen.go
new file mode 100644
index 000000000..b2d8c661f
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/host_unsafe_state_autogen.go
@@ -0,0 +1,3 @@
+// automatically generated by stateify.
+
+package host
diff --git a/pkg/sentry/fsimpl/host/inode_refs.go b/pkg/sentry/fsimpl/host/inode_refs.go
new file mode 100644
index 000000000..8862c4a5e
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/inode_refs.go
@@ -0,0 +1,132 @@
+package host
+
+import (
+ "fmt"
+ "sync/atomic"
+
+ "gvisor.dev/gvisor/pkg/refsvfs2"
+)
+
+// enableLogging indicates whether reference-related events should be logged (with
+// stack traces). This is false by default and should only be set to true for
+// debugging purposes, as it can generate an extremely large amount of output
+// and drastically degrade performance.
+const inodeenableLogging = false
+
+// obj is used to customize logging. Note that we use a pointer to T so that
+// we do not copy the entire object when passed as a format parameter.
+var inodeobj *inode
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// +stateify savable
+type inodeRefs struct {
+ // refCount is composed of two fields:
+ //
+ // [32-bit speculative references]:[32-bit real references]
+ //
+ // Speculative references are used for TryIncRef, to avoid a CompareAndSwap
+ // loop. See IncRef, DecRef and TryIncRef for details of how these fields are
+ // used.
+ refCount int64
+}
+
+// InitRefs initializes r with one reference and, if enabled, activates leak
+// checking.
+func (r *inodeRefs) InitRefs() {
+ atomic.StoreInt64(&r.refCount, 1)
+ refsvfs2.Register(r)
+}
+
+// RefType implements refsvfs2.CheckedObject.RefType.
+func (r *inodeRefs) RefType() string {
+ return fmt.Sprintf("%T", inodeobj)[1:]
+}
+
+// LeakMessage implements refsvfs2.CheckedObject.LeakMessage.
+func (r *inodeRefs) LeakMessage() string {
+ return fmt.Sprintf("[%s %p] reference count of %d instead of 0", r.RefType(), r, r.ReadRefs())
+}
+
+// LogRefs implements refsvfs2.CheckedObject.LogRefs.
+func (r *inodeRefs) LogRefs() bool {
+ return inodeenableLogging
+}
+
+// ReadRefs returns the current number of references. The returned count is
+// inherently racy and is unsafe to use without external synchronization.
+func (r *inodeRefs) ReadRefs() int64 {
+ return atomic.LoadInt64(&r.refCount)
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *inodeRefs) IncRef() {
+ v := atomic.AddInt64(&r.refCount, 1)
+ if inodeenableLogging {
+ refsvfs2.LogIncRef(r, v)
+ }
+ if v <= 1 {
+ panic(fmt.Sprintf("Incrementing non-positive count %p on %s", r, r.RefType()))
+ }
+}
+
+// TryIncRef implements refs.RefCounter.TryIncRef.
+//
+// To do this safely without a loop, a speculative reference is first acquired
+// on the object. This allows multiple concurrent TryIncRef calls to distinguish
+// other TryIncRef calls from genuine references held.
+//
+//go:nosplit
+func (r *inodeRefs) TryIncRef() bool {
+ const speculativeRef = 1 << 32
+ if v := atomic.AddInt64(&r.refCount, speculativeRef); int32(v) == 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ v := atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ if inodeenableLogging {
+ refsvfs2.LogTryIncRef(r, v)
+ }
+ return true
+}
+
+// DecRef implements refs.RefCounter.DecRef.
+//
+// Note that speculative references are counted here. Since they were added
+// prior to real references reaching zero, they will successfully convert to
+// real references. In other words, we see speculative references only in the
+// following case:
+//
+// A: TryIncRef [speculative increase => sees non-negative references]
+// B: DecRef [real decrease]
+// A: TryIncRef [transform speculative to real]
+//
+//go:nosplit
+func (r *inodeRefs) DecRef(destroy func()) {
+ v := atomic.AddInt64(&r.refCount, -1)
+ if inodeenableLogging {
+ refsvfs2.LogDecRef(r, v)
+ }
+ switch {
+ case v < 0:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %s", r, r.RefType()))
+
+ case v == 0:
+ refsvfs2.Unregister(r)
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
+
+func (r *inodeRefs) afterLoad() {
+ if r.ReadRefs() > 0 {
+ refsvfs2.Register(r)
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 08:27:58 +0000