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-rw-r--r--pkg/sentry/fsimpl/host/BUILD78
-rw-r--r--pkg/sentry/fsimpl/host/connected_endpoint_refs.go118
-rw-r--r--pkg/sentry/fsimpl/host/host_state_autogen.go303
-rw-r--r--pkg/sentry/fsimpl/host/host_unsafe_state_autogen.go3
-rw-r--r--pkg/sentry/fsimpl/host/inode_refs.go118
5 files changed, 542 insertions, 78 deletions
diff --git a/pkg/sentry/fsimpl/host/BUILD b/pkg/sentry/fsimpl/host/BUILD
deleted file mode 100644
index 56bcf9bdb..000000000
--- a/pkg/sentry/fsimpl/host/BUILD
+++ /dev/null
@@ -1,78 +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/refs_vfs2:refs_template",
- types = {
- "T": "inode",
- },
-)
-
-go_template_instance(
- name = "connected_endpoint_refs",
- out = "connected_endpoint_refs.go",
- package = "host",
- prefix = "ConnectedEndpoint",
- template = "//pkg/refs_vfs2:refs_template",
- types = {
- "T": "ConnectedEndpoint",
- },
-)
-
-go_library(
- name = "host",
- srcs = [
- "connected_endpoint_refs.go",
- "control.go",
- "host.go",
- "inode_refs.go",
- "ioctl_unsafe.go",
- "mmap.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/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..babb3f664
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
@@ -0,0 +1,118 @@
+package host
+
+import (
+ "fmt"
+ "runtime"
+ "sync/atomic"
+
+ "gvisor.dev/gvisor/pkg/log"
+ refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+)
+
+// ownerType 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 ConnectedEndpointownerType *ConnectedEndpoint
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// Note that the number of references is actually refCount + 1 so that a default
+// zero-value Refs object contains one reference.
+//
+// TODO(gvisor.dev/issue/1486): Store stack traces when leak check is enabled in
+// a map with 16-bit hashes, and store the hash in the top 16 bits of refCount.
+// This will allow us to add stack trace information to the leak messages
+// without growing the size of Refs.
+//
+// +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
+}
+
+func (r *ConnectedEndpointRefs) finalize() {
+ var note string
+ switch refs_vfs1.GetLeakMode() {
+ case refs_vfs1.NoLeakChecking:
+ return
+ case refs_vfs1.UninitializedLeakChecking:
+ note = "(Leak checker uninitialized): "
+ }
+ if n := r.ReadRefs(); n != 0 {
+ log.Warningf("%sRefs %p owned by %T garbage collected with ref count of %d (want 0)", note, r, ConnectedEndpointownerType, n)
+ }
+}
+
+// EnableLeakCheck checks for reference leaks when Refs gets garbage collected.
+func (r *ConnectedEndpointRefs) EnableLeakCheck() {
+ if refs_vfs1.GetLeakMode() != refs_vfs1.NoLeakChecking {
+ runtime.SetFinalizer(r, (*ConnectedEndpointRefs).finalize)
+ }
+}
+
+// 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) + 1
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *ConnectedEndpointRefs) IncRef() {
+ if v := atomic.AddInt64(&r.refCount, 1); v <= 0 {
+ panic(fmt.Sprintf("Incrementing non-positive ref count %p owned by %T", r, ConnectedEndpointownerType))
+ }
+}
+
+// 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
+ v := atomic.AddInt64(&r.refCount, speculativeRef)
+ if int32(v) < 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ 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()) {
+ switch v := atomic.AddInt64(&r.refCount, -1); {
+ case v < -1:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %T", r, ConnectedEndpointownerType))
+
+ case v == -1:
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
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..5aaee37c3
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/host_state_autogen.go
@@ -0,0 +1,303 @@
+// 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) afterLoad() {}
+
+func (r *ConnectedEndpointRefs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &r.refCount)
+}
+
+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 (i *inode) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.inode"
+}
+
+func (i *inode) StateFields() []string {
+ return []string{
+ "InodeNoStatFS",
+ "InodeNotDirectory",
+ "InodeNotSymlink",
+ "InodeTemporary",
+ "locks",
+ "inodeRefs",
+ "hostFD",
+ "ino",
+ "isTTY",
+ "seekable",
+ "wouldBlock",
+ "queue",
+ "canMap",
+ "mappings",
+ "pf",
+ }
+}
+
+func (i *inode) beforeSave() {}
+
+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.InodeTemporary)
+ stateSinkObject.Save(4, &i.locks)
+ stateSinkObject.Save(5, &i.inodeRefs)
+ stateSinkObject.Save(6, &i.hostFD)
+ stateSinkObject.Save(7, &i.ino)
+ stateSinkObject.Save(8, &i.isTTY)
+ stateSinkObject.Save(9, &i.seekable)
+ stateSinkObject.Save(10, &i.wouldBlock)
+ stateSinkObject.Save(11, &i.queue)
+ stateSinkObject.Save(12, &i.canMap)
+ stateSinkObject.Save(13, &i.mappings)
+ stateSinkObject.Save(14, &i.pf)
+}
+
+func (i *inode) afterLoad() {}
+
+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.InodeTemporary)
+ stateSourceObject.Load(4, &i.locks)
+ stateSourceObject.Load(5, &i.inodeRefs)
+ stateSourceObject.Load(6, &i.hostFD)
+ stateSourceObject.Load(7, &i.ino)
+ stateSourceObject.Load(8, &i.isTTY)
+ stateSourceObject.Load(9, &i.seekable)
+ stateSourceObject.Load(10, &i.wouldBlock)
+ stateSourceObject.Load(11, &i.queue)
+ stateSourceObject.Load(12, &i.canMap)
+ stateSourceObject.Load(13, &i.mappings)
+ stateSourceObject.Load(14, &i.pf)
+}
+
+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) afterLoad() {}
+
+func (r *inodeRefs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &r.refCount)
+}
+
+func (i *inodePlatformFile) StateTypeName() string {
+ return "pkg/sentry/fsimpl/host.inodePlatformFile"
+}
+
+func (i *inodePlatformFile) StateFields() []string {
+ return []string{
+ "inode",
+ "fdRefs",
+ "fileMapper",
+ }
+}
+
+func (i *inodePlatformFile) beforeSave() {}
+
+func (i *inodePlatformFile) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.inode)
+ stateSinkObject.Save(1, &i.fdRefs)
+ stateSinkObject.Save(2, &i.fileMapper)
+}
+
+func (i *inodePlatformFile) afterLoad() {}
+
+func (i *inodePlatformFile) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.inode)
+ stateSourceObject.Load(1, &i.fdRefs)
+ stateSourceObject.Load(2, &i.fileMapper)
+}
+
+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((*filesystemType)(nil))
+ state.Register((*filesystem)(nil))
+ state.Register((*inode)(nil))
+ state.Register((*fileDescription)(nil))
+ state.Register((*inodeRefs)(nil))
+ state.Register((*inodePlatformFile)(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..17f90ce4a
--- /dev/null
+++ b/pkg/sentry/fsimpl/host/inode_refs.go
@@ -0,0 +1,118 @@
+package host
+
+import (
+ "fmt"
+ "runtime"
+ "sync/atomic"
+
+ "gvisor.dev/gvisor/pkg/log"
+ refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+)
+
+// ownerType 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 inodeownerType *inode
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// Note that the number of references is actually refCount + 1 so that a default
+// zero-value Refs object contains one reference.
+//
+// TODO(gvisor.dev/issue/1486): Store stack traces when leak check is enabled in
+// a map with 16-bit hashes, and store the hash in the top 16 bits of refCount.
+// This will allow us to add stack trace information to the leak messages
+// without growing the size of Refs.
+//
+// +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
+}
+
+func (r *inodeRefs) finalize() {
+ var note string
+ switch refs_vfs1.GetLeakMode() {
+ case refs_vfs1.NoLeakChecking:
+ return
+ case refs_vfs1.UninitializedLeakChecking:
+ note = "(Leak checker uninitialized): "
+ }
+ if n := r.ReadRefs(); n != 0 {
+ log.Warningf("%sRefs %p owned by %T garbage collected with ref count of %d (want 0)", note, r, inodeownerType, n)
+ }
+}
+
+// EnableLeakCheck checks for reference leaks when Refs gets garbage collected.
+func (r *inodeRefs) EnableLeakCheck() {
+ if refs_vfs1.GetLeakMode() != refs_vfs1.NoLeakChecking {
+ runtime.SetFinalizer(r, (*inodeRefs).finalize)
+ }
+}
+
+// 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) + 1
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *inodeRefs) IncRef() {
+ if v := atomic.AddInt64(&r.refCount, 1); v <= 0 {
+ panic(fmt.Sprintf("Incrementing non-positive ref count %p owned by %T", r, inodeownerType))
+ }
+}
+
+// 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
+ v := atomic.AddInt64(&r.refCount, speculativeRef)
+ if int32(v) < 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ 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()) {
+ switch v := atomic.AddInt64(&r.refCount, -1); {
+ case v < -1:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %T", r, inodeownerType))
+
+ case v == -1:
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-17 14:37:50 +0000