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-rw-r--r--pkg/sentry/kernel/task_block.go2
-rw-r--r--pkg/sentry/socket/netstack/netstack.go176
-rw-r--r--pkg/sentry/socket/netstack/netstack_vfs2.go10
-rw-r--r--pkg/tcpip/adapters/gonet/gonet.go67
-rw-r--r--pkg/tcpip/tcpip.go28
-rw-r--r--pkg/tcpip/transport/icmp/endpoint.go7
-rw-r--r--pkg/tcpip/transport/packet/endpoint.go2
-rw-r--r--pkg/tcpip/transport/raw/endpoint.go6
-rw-r--r--pkg/tcpip/transport/tcp/endpoint.go13
-rw-r--r--pkg/tcpip/transport/udp/endpoint.go6
-rw-r--r--pkg/usermem/usermem.go20
11 files changed, 133 insertions, 204 deletions
diff --git a/pkg/sentry/kernel/task_block.go b/pkg/sentry/kernel/task_block.go
index 9419f2e95..ecbe8f920 100644
--- a/pkg/sentry/kernel/task_block.go
+++ b/pkg/sentry/kernel/task_block.go
@@ -69,7 +69,7 @@ func (t *Task) BlockWithTimeout(C chan struct{}, haveTimeout bool, timeout time.
// syserror.ErrInterrupted if t is interrupted.
//
// Preconditions: The caller must be running on the task goroutine.
-func (t *Task) BlockWithDeadline(C chan struct{}, haveDeadline bool, deadline ktime.Time) error {
+func (t *Task) BlockWithDeadline(C <-chan struct{}, haveDeadline bool, deadline ktime.Time) error {
if !haveDeadline {
return t.block(C, nil)
}
diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index 4c9d335c0..65111154b 100644
--- a/pkg/sentry/socket/netstack/netstack.go
+++ b/pkg/sentry/socket/netstack/netstack.go
@@ -19,7 +19,7 @@
// be used to expose certain endpoints to the sentry while leaving others out,
// for example, TCP endpoints and Unix-domain endpoints.
//
-// Lock ordering: netstack => mm: ioSequencePayload copies user memory inside
+// Lock ordering: netstack => mm: ioSequenceReadWriter copies user memory inside
// tcpip.Endpoint.Write(). Netstack is allowed to (and does) hold locks during
// this operation.
package netstack
@@ -55,7 +55,6 @@ import (
"gvisor.dev/gvisor/pkg/syserr"
"gvisor.dev/gvisor/pkg/syserror"
"gvisor.dev/gvisor/pkg/tcpip"
- "gvisor.dev/gvisor/pkg/tcpip/buffer"
"gvisor.dev/gvisor/pkg/tcpip/header"
"gvisor.dev/gvisor/pkg/tcpip/stack"
"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
@@ -440,45 +439,10 @@ func (s *SocketOperations) WriteTo(ctx context.Context, _ *fs.File, dst io.Write
return int64(res.Count), nil
}
-// ioSequencePayload implements tcpip.Payload.
-//
-// t copies user memory bytes on demand based on the requested size.
-type ioSequencePayload struct {
- ctx context.Context
- src usermem.IOSequence
-}
-
-// FullPayload implements tcpip.Payloader.FullPayload
-func (i *ioSequencePayload) FullPayload() ([]byte, *tcpip.Error) {
- return i.Payload(int(i.src.NumBytes()))
-}
-
-// Payload implements tcpip.Payloader.Payload.
-func (i *ioSequencePayload) Payload(size int) ([]byte, *tcpip.Error) {
- if max := int(i.src.NumBytes()); size > max {
- size = max
- }
- v := buffer.NewView(size)
- if _, err := i.src.CopyIn(i.ctx, v); err != nil {
- // EOF can be returned only if src is a file and this means it
- // is in a splice syscall and the error has to be ignored.
- if err == io.EOF {
- return v, nil
- }
- return nil, tcpip.ErrBadAddress
- }
- return v, nil
-}
-
-// DropFirst drops the first n bytes from underlying src.
-func (i *ioSequencePayload) DropFirst(n int) {
- i.src = i.src.DropFirst(int(n))
-}
-
// Write implements fs.FileOperations.Write.
func (s *SocketOperations) Write(ctx context.Context, _ *fs.File, src usermem.IOSequence, _ int64) (int64, error) {
- f := &ioSequencePayload{ctx: ctx, src: src}
- n, err := s.Endpoint.Write(f, tcpip.WriteOptions{})
+ r := src.Reader(ctx)
+ n, err := s.Endpoint.Write(r, tcpip.WriteOptions{})
if err == tcpip.ErrWouldBlock {
return 0, syserror.ErrWouldBlock
}
@@ -486,69 +450,40 @@ func (s *SocketOperations) Write(ctx context.Context, _ *fs.File, src usermem.IO
return 0, syserr.TranslateNetstackError(err).ToError()
}
- if int64(n) < src.NumBytes() {
- return int64(n), syserror.ErrWouldBlock
+ if n < src.NumBytes() {
+ return n, syserror.ErrWouldBlock
}
- return int64(n), nil
+ return n, nil
}
-// readerPayload implements tcpip.Payloader.
-//
-// It allocates a view and reads from a reader on-demand, based on available
-// capacity in the endpoint.
-type readerPayload struct {
- ctx context.Context
- r io.Reader
- count int64
- err error
-}
+var _ tcpip.Payloader = (*limitedPayloader)(nil)
-// FullPayload implements tcpip.Payloader.FullPayload.
-func (r *readerPayload) FullPayload() ([]byte, *tcpip.Error) {
- return r.Payload(int(r.count))
+type limitedPayloader struct {
+ io.LimitedReader
}
-// Payload implements tcpip.Payloader.Payload.
-func (r *readerPayload) Payload(size int) ([]byte, *tcpip.Error) {
- if size > int(r.count) {
- size = int(r.count)
- }
- v := buffer.NewView(size)
- n, err := r.r.Read(v)
- if n > 0 {
- // We ignore the error here. It may re-occur on subsequent
- // reads, but for now we can enqueue some amount of data.
- r.count -= int64(n)
- return v[:n], nil
- }
- if err == syserror.ErrWouldBlock {
- return nil, tcpip.ErrWouldBlock
- } else if err != nil {
- r.err = err // Save for propation.
- return nil, tcpip.ErrBadAddress
- }
-
- // There is no data and no error. Return an error, which will propagate
- // r.err, which will be nil. This is the desired result: (0, nil).
- return nil, tcpip.ErrBadAddress
+func (l limitedPayloader) Len() int {
+ return int(l.N)
}
// ReadFrom implements fs.FileOperations.ReadFrom.
func (s *SocketOperations) ReadFrom(ctx context.Context, _ *fs.File, r io.Reader, count int64) (int64, error) {
- f := &readerPayload{ctx: ctx, r: r, count: count}
- n, err := s.Endpoint.Write(f, tcpip.WriteOptions{
+ f := limitedPayloader{
+ LimitedReader: io.LimitedReader{
+ R: r,
+ N: count,
+ },
+ }
+ n, err := s.Endpoint.Write(&f, tcpip.WriteOptions{
// Reads may be destructive but should be very fast,
// so we can't release the lock while copying data.
Atomic: true,
})
- if err == tcpip.ErrWouldBlock {
- return n, syserror.ErrWouldBlock
- } else if err != nil {
- return int64(n), f.err // Propagate error.
+ if err == tcpip.ErrBadBuffer {
+ err = nil
}
-
- return int64(n), nil
+ return n, syserr.TranslateNetstackError(err).ToError()
}
// Readiness returns a mask of ready events for socket s.
@@ -2836,45 +2771,46 @@ func (s *socketOpsCommon) SendMsg(t *kernel.Task, src usermem.IOSequence, to []b
EndOfRecord: flags&linux.MSG_EOR != 0,
}
- v := &ioSequencePayload{t, src}
- n, err := s.Endpoint.Write(v, opts)
- dontWait := flags&linux.MSG_DONTWAIT != 0
- if err == nil && (n >= v.src.NumBytes() || dontWait) {
- // Complete write.
- return int(n), nil
- }
- if err != nil && (err != tcpip.ErrWouldBlock || dontWait) {
- return int(n), syserr.TranslateNetstackError(err)
- }
-
- // We'll have to block. Register for notification and keep trying to
- // send all the data.
- e, ch := waiter.NewChannelEntry(nil)
- s.EventRegister(&e, waiter.EventOut)
- defer s.EventUnregister(&e)
-
- v.DropFirst(int(n))
- total := n
+ r := src.Reader(t)
+ var (
+ total int64
+ entry waiter.Entry
+ ch <-chan struct{}
+ )
for {
- n, err = s.Endpoint.Write(v, opts)
- v.DropFirst(int(n))
+ n, err := s.Endpoint.Write(r, opts)
total += n
-
- if err != nil && err != tcpip.ErrWouldBlock && total == 0 {
- return 0, syserr.TranslateNetstackError(err)
- }
-
- if err == nil && v.src.NumBytes() == 0 || err != nil && err != tcpip.ErrWouldBlock {
- return int(total), nil
+ if flags&linux.MSG_DONTWAIT != 0 {
+ return int(total), syserr.TranslateNetstackError(err)
}
-
- if err := t.BlockWithDeadline(ch, haveDeadline, deadline); err != nil {
- if err == syserror.ETIMEDOUT {
- return int(total), syserr.ErrTryAgain
+ switch err {
+ case nil:
+ if total == src.NumBytes() {
+ break
+ }
+ fallthrough
+ case tcpip.ErrWouldBlock:
+ if ch == nil {
+ // We'll have to block. Register for notification and keep trying to
+ // send all the data.
+ entry, ch = waiter.NewChannelEntry(nil)
+ s.EventRegister(&entry, waiter.EventOut)
+ defer s.EventUnregister(&entry)
+ } else {
+ // Don't wait immediately after registration in case more data
+ // became available between when we last checked and when we setup
+ // the notification.
+ if err := t.BlockWithDeadline(ch, haveDeadline, deadline); err != nil {
+ if err == syserror.ETIMEDOUT {
+ return int(total), syserr.ErrTryAgain
+ }
+ // handleIOError will consume errors from t.Block if needed.
+ return int(total), syserr.FromError(err)
+ }
}
- // handleIOError will consume errors from t.Block if needed.
- return int(total), syserr.FromError(err)
+ continue
}
+ return int(total), syserr.TranslateNetstackError(err)
}
}
diff --git a/pkg/sentry/socket/netstack/netstack_vfs2.go b/pkg/sentry/socket/netstack/netstack_vfs2.go
index 9600a64e1..3bbdf552e 100644
--- a/pkg/sentry/socket/netstack/netstack_vfs2.go
+++ b/pkg/sentry/socket/netstack/netstack_vfs2.go
@@ -128,8 +128,8 @@ func (s *SocketVFS2) Write(ctx context.Context, src usermem.IOSequence, opts vfs
return 0, syserror.EOPNOTSUPP
}
- f := &ioSequencePayload{ctx: ctx, src: src}
- n, err := s.Endpoint.Write(f, tcpip.WriteOptions{})
+ r := src.Reader(ctx)
+ n, err := s.Endpoint.Write(r, tcpip.WriteOptions{})
if err == tcpip.ErrWouldBlock {
return 0, syserror.ErrWouldBlock
}
@@ -137,11 +137,11 @@ func (s *SocketVFS2) Write(ctx context.Context, src usermem.IOSequence, opts vfs
return 0, syserr.TranslateNetstackError(err).ToError()
}
- if int64(n) < src.NumBytes() {
- return int64(n), syserror.ErrWouldBlock
+ if n < src.NumBytes() {
+ return n, syserror.ErrWouldBlock
}
- return int64(n), nil
+ return n, nil
}
// Accept implements the linux syscall accept(2) for sockets backed by
diff --git a/pkg/tcpip/adapters/gonet/gonet.go b/pkg/tcpip/adapters/gonet/gonet.go
index fdeec12d3..7c7495c30 100644
--- a/pkg/tcpip/adapters/gonet/gonet.go
+++ b/pkg/tcpip/adapters/gonet/gonet.go
@@ -16,6 +16,7 @@
package gonet
import (
+ "bytes"
"context"
"errors"
"io"
@@ -354,8 +355,6 @@ func (c *TCPConn) Write(b []byte) (int, error) {
default:
}
- v := buffer.NewViewFromBytes(b)
-
// We must handle two soft failure conditions simultaneously:
// 1. Write may write nothing and return tcpip.ErrWouldBlock.
// If this happens, we need to register for notifications if we have
@@ -368,22 +367,23 @@ func (c *TCPConn) Write(b []byte) (int, error) {
// There is no guarantee that all of the condition #1s will occur before
// all of the condition #2s or visa-versa.
var (
- err *tcpip.Error
- nbytes int
- reg bool
- notifyCh chan struct{}
+ r bytes.Reader
+ nbytes int
+ entry waiter.Entry
+ ch <-chan struct{}
)
- for nbytes < len(b) && (err == tcpip.ErrWouldBlock || err == nil) {
- if err == tcpip.ErrWouldBlock {
- if !reg {
- // Only register once.
- reg = true
-
- // Create wait queue entry that notifies a channel.
- var waitEntry waiter.Entry
- waitEntry, notifyCh = waiter.NewChannelEntry(nil)
- c.wq.EventRegister(&waitEntry, waiter.EventOut)
- defer c.wq.EventUnregister(&waitEntry)
+ for nbytes != len(b) {
+ r.Reset(b[nbytes:])
+ n, err := c.ep.Write(&r, tcpip.WriteOptions{})
+ nbytes += int(n)
+ switch err {
+ case nil:
+ case tcpip.ErrWouldBlock:
+ if ch == nil {
+ entry, ch = waiter.NewChannelEntry(nil)
+
+ c.wq.EventRegister(&entry, waiter.EventOut)
+ defer c.wq.EventUnregister(&entry)
} else {
// Don't wait immediately after registration in case more data
// became available between when we last checked and when we setup
@@ -391,22 +391,15 @@ func (c *TCPConn) Write(b []byte) (int, error) {
select {
case <-deadline:
return nbytes, c.newOpError("write", &timeoutError{})
- case <-notifyCh:
+ case <-ch:
+ continue
}
}
+ default:
+ return nbytes, c.newOpError("write", errors.New(err.String()))
}
-
- var n int64
- n, err = c.ep.Write(tcpip.SlicePayload(v), tcpip.WriteOptions{})
- nbytes += int(n)
- v.TrimFront(int(n))
- }
-
- if err == nil {
- return nbytes, nil
}
-
- return nbytes, c.newOpError("write", errors.New(err.String()))
+ return nbytes, nil
}
// Close implements net.Conn.Close.
@@ -644,16 +637,18 @@ func (c *UDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
}
// If we're being called by Write, there is no addr
- wopts := tcpip.WriteOptions{}
+ writeOptions := tcpip.WriteOptions{}
if addr != nil {
ua := addr.(*net.UDPAddr)
- wopts.To = &tcpip.FullAddress{Addr: tcpip.Address(ua.IP), Port: uint16(ua.Port)}
+ writeOptions.To = &tcpip.FullAddress{
+ Addr: tcpip.Address(ua.IP),
+ Port: uint16(ua.Port),
+ }
}
- v := buffer.NewView(len(b))
- copy(v, b)
-
- n, err := c.ep.Write(tcpip.SlicePayload(v), wopts)
+ var r bytes.Reader
+ r.Reset(b)
+ n, err := c.ep.Write(&r, writeOptions)
if err == tcpip.ErrWouldBlock {
// Create wait queue entry that notifies a channel.
waitEntry, notifyCh := waiter.NewChannelEntry(nil)
@@ -666,7 +661,7 @@ func (c *UDPConn) WriteTo(b []byte, addr net.Addr) (int, error) {
case <-notifyCh:
}
- n, err = c.ep.Write(tcpip.SlicePayload(v), wopts)
+ n, err = c.ep.Write(&r, writeOptions)
if err != tcpip.ErrWouldBlock {
break
}
diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go
index 4f59e4ff7..fe01029ad 100644
--- a/pkg/tcpip/tcpip.go
+++ b/pkg/tcpip/tcpip.go
@@ -29,6 +29,7 @@
package tcpip
import (
+ "bytes"
"errors"
"fmt"
"io"
@@ -471,30 +472,15 @@ type FullAddress struct {
// This interface allows the endpoint to request the amount of data it needs
// based on internal buffers without exposing them.
type Payloader interface {
- // FullPayload returns all available bytes.
- FullPayload() ([]byte, *Error)
+ io.Reader
- // Payload returns a slice containing at most size bytes.
- Payload(size int) ([]byte, *Error)
+ // Len returns the number of bytes of the unread portion of the
+ // Reader.
+ Len() int
}
-// SlicePayload implements Payloader for slices.
-//
-// This is typically used for tests.
-type SlicePayload []byte
-
-// FullPayload implements Payloader.FullPayload.
-func (s SlicePayload) FullPayload() ([]byte, *Error) {
- return s, nil
-}
-
-// Payload implements Payloader.Payload.
-func (s SlicePayload) Payload(size int) ([]byte, *Error) {
- if size > len(s) {
- size = len(s)
- }
- return s[:size], nil
-}
+var _ Payloader = (*bytes.Buffer)(nil)
+var _ Payloader = (*bytes.Reader)(nil)
var _ io.Writer = (*SliceWriter)(nil)
diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index 256e19296..af00ed548 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -313,11 +313,12 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, *tc
route = r
}
- v, err := p.FullPayload()
- if err != nil {
- return 0, err
+ v := make([]byte, p.Len())
+ if _, err := io.ReadFull(p, v); err != nil {
+ return 0, tcpip.ErrBadBuffer
}
+ var err *tcpip.Error
switch e.NetProto {
case header.IPv4ProtocolNumber:
err = send4(route, e.ID.LocalPort, v, e.ttl, e.owner)
diff --git a/pkg/tcpip/transport/packet/endpoint.go b/pkg/tcpip/transport/packet/endpoint.go
index c0d6fb442..6fd116a98 100644
--- a/pkg/tcpip/transport/packet/endpoint.go
+++ b/pkg/tcpip/transport/packet/endpoint.go
@@ -207,7 +207,7 @@ func (ep *endpoint) Read(dst io.Writer, opts tcpip.ReadOptions) (tcpip.ReadResul
return res, nil
}
-func (*endpoint) Write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, *tcpip.Error) {
+func (*endpoint) Write(tcpip.Payloader, tcpip.WriteOptions) (int64, *tcpip.Error) {
// TODO(gvisor.dev/issue/173): Implement.
return 0, tcpip.ErrInvalidOptionValue
}
diff --git a/pkg/tcpip/transport/raw/endpoint.go b/pkg/tcpip/transport/raw/endpoint.go
index ae743f75e..2dacf5a64 100644
--- a/pkg/tcpip/transport/raw/endpoint.go
+++ b/pkg/tcpip/transport/raw/endpoint.go
@@ -280,9 +280,9 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, *tc
return 0, tcpip.ErrInvalidEndpointState
}
- payloadBytes, err := p.FullPayload()
- if err != nil {
- return 0, err
+ payloadBytes := make([]byte, p.Len())
+ if _, err := io.ReadFull(p, payloadBytes); err != nil {
+ return 0, tcpip.ErrBadBuffer
}
// If this is an unassociated socket and callee provided a nonzero
diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go
index ea509ac73..8d27d43c2 100644
--- a/pkg/tcpip/transport/tcp/endpoint.go
+++ b/pkg/tcpip/transport/tcp/endpoint.go
@@ -1534,14 +1534,19 @@ func (e *endpoint) Write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, *tc
}
// Fetch data.
- v, perr := p.Payload(avail)
- if perr != nil || len(v) == 0 {
- // Note that perr may be nil if len(v) == 0.
+ if l := p.Len(); l < avail {
+ avail = l
+ }
+ if avail == 0 {
+ return 0, nil
+ }
+ v := make([]byte, avail)
+ if _, err := io.ReadFull(p, v); err != nil {
if opts.Atomic {
e.sndBufMu.Unlock()
e.UnlockUser()
}
- return 0, perr
+ return 0, tcpip.ErrBadBuffer
}
if !opts.Atomic {
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index 9f9b3d510..8544fcb08 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -514,9 +514,9 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, *tc
return 0, tcpip.ErrBroadcastDisabled
}
- v, err := p.FullPayload()
- if err != nil {
- return 0, err
+ v := make([]byte, p.Len())
+ if _, err := io.ReadFull(p, v); err != nil {
+ return 0, tcpip.ErrBadBuffer
}
if len(v) > header.UDPMaximumPacketSize {
// Payload can't possibly fit in a packet.
diff --git a/pkg/usermem/usermem.go b/pkg/usermem/usermem.go
index 79db8895b..dc2571154 100644
--- a/pkg/usermem/usermem.go
+++ b/pkg/usermem/usermem.go
@@ -517,28 +517,29 @@ func (s IOSequence) CopyInTo(ctx context.Context, dst safemem.Writer) (int64, er
// Reader returns an io.Reader that reads from s. Reads beyond the end of s
// return io.EOF. The preconditions that apply to s.CopyIn also apply to the
// returned io.Reader.Read.
-func (s IOSequence) Reader(ctx context.Context) io.Reader {
- return &ioSequenceReadWriter{ctx, s}
+func (s IOSequence) Reader(ctx context.Context) *IOSequenceReadWriter {
+ return &IOSequenceReadWriter{ctx, s}
}
// Writer returns an io.Writer that writes to s. Writes beyond the end of s
// return ErrEndOfIOSequence. The preconditions that apply to s.CopyOut also
// apply to the returned io.Writer.Write.
-func (s IOSequence) Writer(ctx context.Context) io.Writer {
- return &ioSequenceReadWriter{ctx, s}
+func (s IOSequence) Writer(ctx context.Context) *IOSequenceReadWriter {
+ return &IOSequenceReadWriter{ctx, s}
}
// ErrEndOfIOSequence is returned by IOSequence.Writer().Write() when
// attempting to write beyond the end of the IOSequence.
var ErrEndOfIOSequence = errors.New("write beyond end of IOSequence")
-type ioSequenceReadWriter struct {
+// IOSequenceReadWriter implements io.Reader and io.Writer for an IOSequence.
+type IOSequenceReadWriter struct {
ctx context.Context
s IOSequence
}
// Read implements io.Reader.Read.
-func (rw *ioSequenceReadWriter) Read(dst []byte) (int, error) {
+func (rw *IOSequenceReadWriter) Read(dst []byte) (int, error) {
n, err := rw.s.CopyIn(rw.ctx, dst)
rw.s = rw.s.DropFirst(n)
if err == nil && rw.s.NumBytes() == 0 {
@@ -547,8 +548,13 @@ func (rw *ioSequenceReadWriter) Read(dst []byte) (int, error) {
return n, err
}
+// Len implements tcpip.Payloader.
+func (rw *IOSequenceReadWriter) Len() int {
+ return int(rw.s.NumBytes())
+}
+
// Write implements io.Writer.Write.
-func (rw *ioSequenceReadWriter) Write(src []byte) (int, error) {
+func (rw *IOSequenceReadWriter) Write(src []byte) (int, error) {
n, err := rw.s.CopyOut(rw.ctx, src)
rw.s = rw.s.DropFirst(n)
if err == nil && n < len(src) {
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-08 15:15:41 +0000