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-rw-r--r--pkg/sentry/fs/BUILD2
-rw-r--r--pkg/sentry/fs/fdpipe/pipe_opener_test.go1
-rw-r--r--pkg/sentry/fs/flags.go7
-rw-r--r--pkg/sentry/fs/gofer/file_state.go8
-rw-r--r--pkg/sentry/fs/gofer/handles.go5
-rw-r--r--pkg/sentry/fs/gofer/inode.go18
-rw-r--r--pkg/sentry/fs/host/BUILD2
-rw-r--r--pkg/sentry/fs/host/util.go2
-rw-r--r--pkg/sentry/fs/host/util_amd64_unsafe.go41
-rw-r--r--pkg/sentry/fs/host/util_arm64_unsafe.go41
-rw-r--r--pkg/sentry/fs/host/util_unsafe.go19
-rw-r--r--pkg/sentry/fs/inode.go4
-rw-r--r--pkg/sentry/fs/inode_overlay.go4
-rw-r--r--pkg/sentry/fs/overlay.go4
-rw-r--r--pkg/sentry/fs/tty/master.go1
-rw-r--r--pkg/sentry/fs/tty/slave.go1
16 files changed, 128 insertions, 32 deletions
diff --git a/pkg/sentry/fs/BUILD b/pkg/sentry/fs/BUILD
index 378602cc9..c035ffff7 100644
--- a/pkg/sentry/fs/BUILD
+++ b/pkg/sentry/fs/BUILD
@@ -68,9 +68,9 @@ go_library(
"//pkg/sentry/usage",
"//pkg/sentry/usermem",
"//pkg/state",
+ "//pkg/syncutil",
"//pkg/syserror",
"//pkg/waiter",
- "//third_party/gvsync",
],
)
diff --git a/pkg/sentry/fs/fdpipe/pipe_opener_test.go b/pkg/sentry/fs/fdpipe/pipe_opener_test.go
index 8e4d839e1..577445148 100644
--- a/pkg/sentry/fs/fdpipe/pipe_opener_test.go
+++ b/pkg/sentry/fs/fdpipe/pipe_opener_test.go
@@ -25,6 +25,7 @@ import (
"time"
"github.com/google/uuid"
+
"gvisor.dev/gvisor/pkg/fd"
"gvisor.dev/gvisor/pkg/sentry/context"
"gvisor.dev/gvisor/pkg/sentry/context/contexttest"
diff --git a/pkg/sentry/fs/flags.go b/pkg/sentry/fs/flags.go
index 0fab876a9..4338ae1fa 100644
--- a/pkg/sentry/fs/flags.go
+++ b/pkg/sentry/fs/flags.go
@@ -64,6 +64,10 @@ type FileFlags struct {
// NonSeekable indicates that file.offset isn't used.
NonSeekable bool
+
+ // Truncate indicates that the file should be truncated before opened.
+ // This is only applicable if the file is regular.
+ Truncate bool
}
// SettableFileFlags is a subset of FileFlags above that can be changed
@@ -118,6 +122,9 @@ func (f FileFlags) ToLinux() (mask uint) {
if f.LargeFile {
mask |= linux.O_LARGEFILE
}
+ if f.Truncate {
+ mask |= linux.O_TRUNC
+ }
switch {
case f.Read && f.Write:
diff --git a/pkg/sentry/fs/gofer/file_state.go b/pkg/sentry/fs/gofer/file_state.go
index c2fbb4be9..bb8312849 100644
--- a/pkg/sentry/fs/gofer/file_state.go
+++ b/pkg/sentry/fs/gofer/file_state.go
@@ -28,8 +28,14 @@ func (f *fileOperations) afterLoad() {
// Manually load the open handles.
var err error
+
+ // The file may have been opened with Truncate, but we don't
+ // want to re-open it with Truncate or we will lose data.
+ flags := f.flags
+ flags.Truncate = false
+
// TODO(b/38173783): Context is not plumbed to save/restore.
- f.handles, err = f.inodeOperations.fileState.getHandles(context.Background(), f.flags, f.inodeOperations.cachingInodeOps)
+ f.handles, err = f.inodeOperations.fileState.getHandles(context.Background(), flags, f.inodeOperations.cachingInodeOps)
if err != nil {
return fmt.Errorf("failed to re-open handle: %v", err)
}
diff --git a/pkg/sentry/fs/gofer/handles.go b/pkg/sentry/fs/gofer/handles.go
index 39c8ec33d..b86c49b39 100644
--- a/pkg/sentry/fs/gofer/handles.go
+++ b/pkg/sentry/fs/gofer/handles.go
@@ -64,7 +64,7 @@ func (h *handles) DecRef() {
})
}
-func newHandles(ctx context.Context, file contextFile, flags fs.FileFlags) (*handles, error) {
+func newHandles(ctx context.Context, client *p9.Client, file contextFile, flags fs.FileFlags) (*handles, error) {
_, newFile, err := file.walk(ctx, nil)
if err != nil {
return nil, err
@@ -81,6 +81,9 @@ func newHandles(ctx context.Context, file contextFile, flags fs.FileFlags) (*han
default:
panic("impossible fs.FileFlags")
}
+ if flags.Truncate && p9.VersionSupportsOpenTruncateFlag(client.Version()) {
+ p9flags |= p9.OpenTruncate
+ }
hostFile, _, _, err := newFile.open(ctx, p9flags)
if err != nil {
diff --git a/pkg/sentry/fs/gofer/inode.go b/pkg/sentry/fs/gofer/inode.go
index 54a8ceef8..91263ebdc 100644
--- a/pkg/sentry/fs/gofer/inode.go
+++ b/pkg/sentry/fs/gofer/inode.go
@@ -180,7 +180,7 @@ func (i *inodeFileState) setSharedHandlesLocked(flags fs.FileFlags, h *handles)
// given flags.
func (i *inodeFileState) getHandles(ctx context.Context, flags fs.FileFlags, cache *fsutil.CachingInodeOperations) (*handles, error) {
if !i.canShareHandles() {
- return newHandles(ctx, i.file, flags)
+ return newHandles(ctx, i.s.client, i.file, flags)
}
i.handlesMu.Lock()
@@ -201,19 +201,25 @@ func (i *inodeFileState) getHandles(ctx context.Context, flags fs.FileFlags, cac
// whether previously open read handle was recreated. Host mappings must be
// invalidated if so.
func (i *inodeFileState) getHandlesLocked(ctx context.Context, flags fs.FileFlags) (*handles, bool, error) {
- // Do we already have usable shared handles?
- if flags.Write {
+ // Check if we are able to use cached handles.
+ if flags.Truncate && p9.VersionSupportsOpenTruncateFlag(i.s.client.Version()) {
+ // If we are truncating (and the gofer supports it), then we
+ // always need a new handle. Don't return one from the cache.
+ } else if flags.Write {
if i.writeHandles != nil && (i.writeHandlesRW || !flags.Read) {
+ // File is opened for writing, and we have cached write
+ // handles that we can use.
i.writeHandles.IncRef()
return i.writeHandles, false, nil
}
} else if i.readHandles != nil {
+ // File is opened for reading and we have cached handles.
i.readHandles.IncRef()
return i.readHandles, false, nil
}
- // No; get new handles and cache them for future sharing.
- h, err := newHandles(ctx, i.file, flags)
+ // Get new handles and cache them for future sharing.
+ h, err := newHandles(ctx, i.s.client, i.file, flags)
if err != nil {
return nil, false, err
}
@@ -239,7 +245,7 @@ func (i *inodeFileState) recreateReadHandles(ctx context.Context, writer *handle
if !flags.Read {
// Writer can't be used for read, must create a new handle.
var err error
- h, err = newHandles(ctx, i.file, fs.FileFlags{Read: true})
+ h, err = newHandles(ctx, i.s.client, i.file, fs.FileFlags{Read: true})
if err != nil {
return err
}
diff --git a/pkg/sentry/fs/host/BUILD b/pkg/sentry/fs/host/BUILD
index 1cbed07ae..23daeb528 100644
--- a/pkg/sentry/fs/host/BUILD
+++ b/pkg/sentry/fs/host/BUILD
@@ -21,6 +21,8 @@ go_library(
"socket_unsafe.go",
"tty.go",
"util.go",
+ "util_amd64_unsafe.go",
+ "util_arm64_unsafe.go",
"util_unsafe.go",
],
importpath = "gvisor.dev/gvisor/pkg/sentry/fs/host",
diff --git a/pkg/sentry/fs/host/util.go b/pkg/sentry/fs/host/util.go
index bad61a9a1..e37e687c6 100644
--- a/pkg/sentry/fs/host/util.go
+++ b/pkg/sentry/fs/host/util.go
@@ -155,7 +155,7 @@ func unstableAttr(mo *superOperations, s *syscall.Stat_t) fs.UnstableAttr {
AccessTime: ktime.FromUnix(s.Atim.Sec, s.Atim.Nsec),
ModificationTime: ktime.FromUnix(s.Mtim.Sec, s.Mtim.Nsec),
StatusChangeTime: ktime.FromUnix(s.Ctim.Sec, s.Ctim.Nsec),
- Links: s.Nlink,
+ Links: uint64(s.Nlink),
}
}
diff --git a/pkg/sentry/fs/host/util_amd64_unsafe.go b/pkg/sentry/fs/host/util_amd64_unsafe.go
new file mode 100644
index 000000000..66da6e9f5
--- /dev/null
+++ b/pkg/sentry/fs/host/util_amd64_unsafe.go
@@ -0,0 +1,41 @@
+// Copyright 2019 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.
+
+// +build amd64
+
+package host
+
+import (
+ "syscall"
+ "unsafe"
+)
+
+func fstatat(fd int, name string, flags int) (syscall.Stat_t, error) {
+ var stat syscall.Stat_t
+ namePtr, err := syscall.BytePtrFromString(name)
+ if err != nil {
+ return stat, err
+ }
+ _, _, errno := syscall.Syscall6(
+ syscall.SYS_NEWFSTATAT,
+ uintptr(fd),
+ uintptr(unsafe.Pointer(namePtr)),
+ uintptr(unsafe.Pointer(&stat)),
+ uintptr(flags),
+ 0, 0)
+ if errno != 0 {
+ return stat, errno
+ }
+ return stat, nil
+}
diff --git a/pkg/sentry/fs/host/util_arm64_unsafe.go b/pkg/sentry/fs/host/util_arm64_unsafe.go
new file mode 100644
index 000000000..e8cb94aeb
--- /dev/null
+++ b/pkg/sentry/fs/host/util_arm64_unsafe.go
@@ -0,0 +1,41 @@
+// Copyright 2019 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.
+
+// +build arm64
+
+package host
+
+import (
+ "syscall"
+ "unsafe"
+)
+
+func fstatat(fd int, name string, flags int) (syscall.Stat_t, error) {
+ var stat syscall.Stat_t
+ namePtr, err := syscall.BytePtrFromString(name)
+ if err != nil {
+ return stat, err
+ }
+ _, _, errno := syscall.Syscall6(
+ syscall.SYS_FSTATAT,
+ uintptr(fd),
+ uintptr(unsafe.Pointer(namePtr)),
+ uintptr(unsafe.Pointer(&stat)),
+ uintptr(flags),
+ 0, 0)
+ if errno != 0 {
+ return stat, errno
+ }
+ return stat, nil
+}
diff --git a/pkg/sentry/fs/host/util_unsafe.go b/pkg/sentry/fs/host/util_unsafe.go
index 2b76f1065..3ab36b088 100644
--- a/pkg/sentry/fs/host/util_unsafe.go
+++ b/pkg/sentry/fs/host/util_unsafe.go
@@ -116,22 +116,3 @@ func setTimestamps(fd int, ts fs.TimeSpec) error {
}
return nil
}
-
-func fstatat(fd int, name string, flags int) (syscall.Stat_t, error) {
- var stat syscall.Stat_t
- namePtr, err := syscall.BytePtrFromString(name)
- if err != nil {
- return stat, err
- }
- _, _, errno := syscall.Syscall6(
- syscall.SYS_NEWFSTATAT,
- uintptr(fd),
- uintptr(unsafe.Pointer(namePtr)),
- uintptr(unsafe.Pointer(&stat)),
- uintptr(flags),
- 0, 0)
- if errno != 0 {
- return stat, errno
- }
- return stat, nil
-}
diff --git a/pkg/sentry/fs/inode.go b/pkg/sentry/fs/inode.go
index f4ddfa406..2d43dff1d 100644
--- a/pkg/sentry/fs/inode.go
+++ b/pkg/sentry/fs/inode.go
@@ -344,6 +344,10 @@ func (i *Inode) SetTimestamps(ctx context.Context, d *Dirent, ts TimeSpec) error
// Truncate calls i.InodeOperations.Truncate with i as the Inode.
func (i *Inode) Truncate(ctx context.Context, d *Dirent, size int64) error {
+ if IsDir(i.StableAttr) {
+ return syserror.EISDIR
+ }
+
if i.overlay != nil {
return overlayTruncate(ctx, i.overlay, d, size)
}
diff --git a/pkg/sentry/fs/inode_overlay.go b/pkg/sentry/fs/inode_overlay.go
index 5a388dad1..a09147080 100644
--- a/pkg/sentry/fs/inode_overlay.go
+++ b/pkg/sentry/fs/inode_overlay.go
@@ -462,7 +462,9 @@ func overlayBind(ctx context.Context, o *overlayEntry, parent *Dirent, name stri
inode.DecRef()
return nil, err
}
- return NewDirent(ctx, newOverlayInode(ctx, entry, inode.MountSource), name), nil
+ // Use the parent's MountSource, since that corresponds to the overlay,
+ // and not the upper filesystem.
+ return NewDirent(ctx, newOverlayInode(ctx, entry, parent.Inode.MountSource), name), nil
}
func overlayBoundEndpoint(o *overlayEntry, path string) transport.BoundEndpoint {
diff --git a/pkg/sentry/fs/overlay.go b/pkg/sentry/fs/overlay.go
index 1d3ff39e0..25573e986 100644
--- a/pkg/sentry/fs/overlay.go
+++ b/pkg/sentry/fs/overlay.go
@@ -23,8 +23,8 @@ import (
"gvisor.dev/gvisor/pkg/sentry/context"
"gvisor.dev/gvisor/pkg/sentry/memmap"
"gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/syncutil"
"gvisor.dev/gvisor/pkg/syserror"
- "gvisor.dev/gvisor/third_party/gvsync"
)
// The virtual filesystem implements an overlay configuration. For a high-level
@@ -199,7 +199,7 @@ type overlayEntry struct {
upper *Inode
// dirCacheMu protects dirCache.
- dirCacheMu gvsync.DowngradableRWMutex `state:"nosave"`
+ dirCacheMu syncutil.DowngradableRWMutex `state:"nosave"`
// dirCache is cache of DentAttrs from upper and lower Inodes.
dirCache *SortedDentryMap
diff --git a/pkg/sentry/fs/tty/master.go b/pkg/sentry/fs/tty/master.go
index 19b7557d5..bc56be696 100644
--- a/pkg/sentry/fs/tty/master.go
+++ b/pkg/sentry/fs/tty/master.go
@@ -32,6 +32,7 @@ import (
// +stateify savable
type masterInodeOperations struct {
fsutil.SimpleFileInode
+ fsutil.InodeNoopTruncate
// d is the containing dir.
d *dirInodeOperations
diff --git a/pkg/sentry/fs/tty/slave.go b/pkg/sentry/fs/tty/slave.go
index 944c4ada1..4cbea0367 100644
--- a/pkg/sentry/fs/tty/slave.go
+++ b/pkg/sentry/fs/tty/slave.go
@@ -31,6 +31,7 @@ import (
// +stateify savable
type slaveInodeOperations struct {
fsutil.SimpleFileInode
+ fsutil.InodeNoopTruncate
// d is the containing dir.
d *dirInodeOperations
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-27 05:20:24 +0000