snapshot: sagernet/gvisor v0.0.0-20250811.0-sing-box-mod.1

Содержимое пина, зафиксированного в go.mod sing-box-lx, одним коммитом
без истории. Полная история SagerNet/gvisor — 1.45 ГБ и клонируется в
каждой CI-джобе; наша дельта — одна вставка в одну функцию, история для
неё не нужна.

Module path github.com/sagernet/gvisor сохранён намеренно: на него
опирается replace-директива суперпроекта.

Патч поверх — отдельным коммитом, чтобы дельта читалась одним git show
и переносилась на новый пин копированием.

SPECS/TASKS/048-GVISOR_HANDSHAKE_NIL_CRASH

pkg/rawfile/blockingpoll_amd64.s

@@ -0,0 +1,41 @@
+// Copyright 2018 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.
+
+#include "textflag.h"
+
+// BlockingPoll makes the ppoll() syscall while calling the version of
+// entersyscall that relinquishes the P so that other Gs can run. This is meant
+// to be called in cases when the syscall is expected to block.
+//
+// func BlockingPoll(fds *PollEvent, nfds int, timeout *syscall.Timespec) (n int, err syscall.Errno)
+TEXT ·BlockingPoll(SB),NOSPLIT|NOFRAME,$0-40
+	CALL	·callEntersyscallblock(SB)
+	MOVQ	fds+0(FP), DI
+	MOVQ	nfds+8(FP), SI
+	MOVQ	timeout+16(FP), DX
+	MOVQ	$0x0, R10  // sigmask parameter which isn't used here
+	MOVQ	$0x10f, AX // SYS_PPOLL
+	SYSCALL
+	CMPQ	AX, $0xfffffffffffff002
+	JLS	ok
+	MOVQ	$-1, ret+24(FP)
+	NEGQ	AX
+	MOVQ	AX, ret1+32(FP)
+	CALL	·callExitsyscall(SB)
+	RET
+ok:
+	MOVQ	AX, ret+24(FP)
+	MOVQ	$0, ret1+32(FP)
+	CALL	·callExitsyscall(SB)
+	RET

pkg/rawfile/blockingpoll_arm64.s

@@ -0,0 +1,42 @@
+// Copyright 2018 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.
+
+#include "textflag.h"
+
+// BlockingPoll makes the ppoll() syscall while calling the version of
+// entersyscall that relinquishes the P so that other Gs can run. This is meant
+// to be called in cases when the syscall is expected to block.
+//
+// func BlockingPoll(fds *PollEvent, nfds int, timeout *syscall.Timespec) (n int, err syscall.Errno)
+TEXT ·BlockingPoll(SB),NOSPLIT,$0-40
+	BL	·callEntersyscallblock(SB)
+	MOVD	fds+0(FP), R0
+	MOVD	nfds+8(FP), R1
+	MOVD	timeout+16(FP), R2
+	MOVD	$0x0, R3  // sigmask parameter which isn't used here
+	MOVD	$0x49, R8 // SYS_PPOLL
+	SVC
+	CMP	$0xfffffffffffff002, R0
+	BLS	ok
+	MOVD	$-1, R1
+	MOVD	R1, ret+24(FP)
+	NEG	R0, R0
+	MOVD	R0, ret1+32(FP)
+	BL	·callExitsyscall(SB)
+	RET
+ok:
+	MOVD	R0, ret+24(FP)
+	MOVD	$0, ret1+32(FP)
+	BL	·callExitsyscall(SB)
+	RET

pkg/rawfile/blockingpoll_noyield_unsafe.go

@@ -0,0 +1,33 @@
+// Copyright 2018 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.
+
+//go:build linux && !amd64 && !arm64
+// +build linux,!amd64,!arm64
+
+package rawfile
+
+import (
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+// BlockingPoll is just a stub function that forwards to the ppoll() system call
+// on non-amd64 and non-arm64 platforms.
+func BlockingPoll(fds *PollEvent, nfds int, timeout *unix.Timespec) (int, unix.Errno) {
+	n, _, e := unix.Syscall6(unix.SYS_PPOLL, uintptr(unsafe.Pointer(fds)),
+		uintptr(nfds), uintptr(unsafe.Pointer(timeout)), 0, 0, 0)
+
+	return int(n), e
+}

pkg/rawfile/blockingpoll_yield_unsafe.go

@@ -0,0 +1,69 @@
+// Copyright 2018 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.
+
+//go:build ((linux && amd64) || (linux && arm64)) && go1.18
+// +build linux,amd64 linux,arm64
+// +build go1.18
+
+// //go:linkname directives type-checked by checklinkname. Any other
+// non-linkname assumptions outside the Go 1 compatibility guarantee should
+// have an accompanied vet check or version guard build tag.
+
+package rawfile
+
+import (
+	_ "unsafe" // for go:linkname
+
+	"golang.org/x/sys/unix"
+)
+
+// BlockingPoll on amd64/arm64 makes the ppoll() syscall while calling the
+// version of entersyscall that relinquishes the P so that other Gs can
+// run. This is meant to be called in cases when the syscall is expected to
+// block. On non amd64/arm64 platforms it just forwards to the ppoll() system
+// call.
+//
+//go:noescape
+func BlockingPoll(fds *PollEvent, nfds int, timeout *unix.Timespec) (int, unix.Errno)
+
+// Use go:linkname to call into the runtime. As of Go 1.13 this has to
+// be done from Go code so that we make an ABIInternal call to an
+// ABIInternal function; see https://golang.org/issue/27539.
+
+// We need to call both entersyscallblock and exitsyscall this way so
+// that the runtime's check on the stack pointer lines up.
+
+// Note that calling an unexported function in the runtime package is
+// unsafe and this hack is likely to break in future Go releases.
+
+//go:linkname entersyscallblock runtime.entersyscallblock
+func entersyscallblock()
+
+//go:linkname exitsyscall runtime.exitsyscall
+func exitsyscall()
+
+// These forwarding functions must be nosplit because 1) we must
+// disallow preemption between entersyscallblock and exitsyscall, and
+// 2) we have an untyped assembly frame on the stack which can not be
+// grown or moved.
+
+//go:nosplit
+func callEntersyscallblock() {
+	entersyscallblock()
+}
+
+//go:nosplit
+func callExitsyscall() {
+	exitsyscall()
+}

pkg/rawfile/rawfile_unsafe.go

@@ -0,0 +1,233 @@
+// Copyright 2018 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.
+
+//go:build linux
+// +build linux
+
+// Package rawfile contains utilities for using raw host files on Linux hosts.
+package rawfile
+
+import (
+	"reflect"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+// SizeofIovec is the size of a unix.Iovec in bytes.
+const SizeofIovec = unsafe.Sizeof(unix.Iovec{})
+
+// MaxIovs is UIO_MAXIOV, the maximum number of iovecs that may be passed to a
+// host system call in a single array.
+const MaxIovs = 1024
+
+// IovecFromBytes returns a unix.Iovec representing bs.
+//
+// Preconditions: len(bs) > 0.
+func IovecFromBytes(bs []byte) unix.Iovec {
+	iov := unix.Iovec{
+		Base: &bs[0],
+	}
+	iov.SetLen(len(bs))
+	return iov
+}
+
+func bytesFromIovec(iov unix.Iovec) (bs []byte) {
+	sh := (*reflect.SliceHeader)(unsafe.Pointer(&bs))
+	sh.Data = uintptr(unsafe.Pointer(iov.Base))
+	sh.Len = int(iov.Len)
+	sh.Cap = int(iov.Len)
+	return
+}
+
+// AppendIovecFromBytes returns append(iovs, IovecFromBytes(bs)). If len(bs) ==
+// 0, AppendIovecFromBytes returns iovs without modification. If len(iovs) >=
+// max, AppendIovecFromBytes replaces the final iovec in iovs with one that
+// also includes the contents of bs. Note that this implies that
+// AppendIovecFromBytes is only usable when the returned iovec slice is used as
+// the source of a write.
+func AppendIovecFromBytes(iovs []unix.Iovec, bs []byte, max int) []unix.Iovec {
+	if len(bs) == 0 {
+		return iovs
+	}
+	if len(iovs) < max {
+		return append(iovs, IovecFromBytes(bs))
+	}
+	iovs[len(iovs)-1] = IovecFromBytes(append(bytesFromIovec(iovs[len(iovs)-1]), bs...))
+	return iovs
+}
+
+// MMsgHdr represents the mmsg_hdr structure required by recvmmsg() on linux.
+type MMsgHdr struct {
+	Msg unix.Msghdr
+	Len uint32
+	_   [4]byte
+}
+
+// SizeofMMsgHdr is the size of a MMsgHdr in bytes.
+const SizeofMMsgHdr = unsafe.Sizeof(MMsgHdr{})
+
+// GetMTU determines the MTU of a network interface device.
+func GetMTU(name string) (uint32, error) {
+	fd, err := unix.Socket(unix.AF_UNIX, unix.SOCK_DGRAM, 0)
+	if err != nil {
+		return 0, err
+	}
+
+	defer unix.Close(fd)
+
+	var ifreq struct {
+		name [16]byte
+		mtu  int32
+		_    [20]byte
+	}
+
+	copy(ifreq.name[:], name)
+	_, _, errno := unix.Syscall(unix.SYS_IOCTL, uintptr(fd), unix.SIOCGIFMTU, uintptr(unsafe.Pointer(&ifreq)))
+	if errno != 0 {
+		return 0, errno
+	}
+
+	return uint32(ifreq.mtu), nil
+}
+
+// NonBlockingWrite writes the given buffer to a file descriptor. It fails if
+// partial data is written.
+func NonBlockingWrite(fd int, buf []byte) unix.Errno {
+	var ptr unsafe.Pointer
+	if len(buf) > 0 {
+		ptr = unsafe.Pointer(&buf[0])
+	}
+
+	_, _, e := unix.RawSyscall(unix.SYS_WRITE, uintptr(fd), uintptr(ptr), uintptr(len(buf)))
+	return e
+}
+
+// NonBlockingWriteIovec writes iovec to a file descriptor in a single unix.
+// It fails if partial data is written.
+func NonBlockingWriteIovec(fd int, iovec []unix.Iovec) unix.Errno {
+	iovecLen := uintptr(len(iovec))
+	_, _, e := unix.RawSyscall(unix.SYS_WRITEV, uintptr(fd), uintptr(unsafe.Pointer(&iovec[0])), iovecLen)
+	return e
+}
+
+// NonBlockingSendMMsg sends multiple messages on a socket.
+func NonBlockingSendMMsg(fd int, msgHdrs []MMsgHdr) (int, unix.Errno) {
+	n, _, e := unix.RawSyscall6(unix.SYS_SENDMMSG, uintptr(fd), uintptr(unsafe.Pointer(&msgHdrs[0])), uintptr(len(msgHdrs)), unix.MSG_DONTWAIT, 0, 0)
+	return int(n), e
+}
+
+// PollEvent represents the pollfd structure passed to a poll() system call.
+type PollEvent struct {
+	FD      int32
+	Events  int16
+	Revents int16
+}
+
+// BlockingRead reads from a file descriptor that is set up as non-blocking.
+// If no data is available, it will block in a poll() syscall  until the file
+// descriptor becomes readable.
+func BlockingRead(fd int, b []byte) (int, unix.Errno) {
+	for {
+		n, _, e := unix.RawSyscall(unix.SYS_READ, uintptr(fd), uintptr(unsafe.Pointer(&b[0])), uintptr(len(b)))
+		if e == 0 {
+			return int(n), 0
+		}
+
+		event := PollEvent{
+			FD:     int32(fd),
+			Events: 1, // POLLIN
+		}
+
+		_, e = BlockingPoll(&event, 1, nil)
+		if e != 0 && e != unix.EINTR {
+			return 0, e
+		}
+	}
+}
+
+// BlockingReadvUntilStopped reads from a file descriptor that is set up as
+// non-blocking and stores the data in a list of iovecs buffers. If no data is
+// available, it will block in a poll() syscall until the file descriptor
+// becomes readable or stop is signalled (efd becomes readable). Returns -1 in
+// the latter case.
+func BlockingReadvUntilStopped(efd int, fd int, iovecs []unix.Iovec) (int, unix.Errno) {
+	for {
+		n, _, e := unix.RawSyscall(unix.SYS_READV, uintptr(fd), uintptr(unsafe.Pointer(&iovecs[0])), uintptr(len(iovecs)))
+		if e == 0 {
+			return int(n), 0
+		}
+		if e != 0 && e != unix.EWOULDBLOCK {
+			return 0, e
+		}
+		stopped, e := BlockingPollUntilStopped(efd, fd, unix.POLLIN)
+		if stopped {
+			return -1, e
+		}
+		if e != 0 && e != unix.EINTR {
+			return 0, e
+		}
+	}
+}
+
+// BlockingRecvMMsgUntilStopped reads from a file descriptor that is set up as
+// non-blocking and stores the received messages in a slice of MMsgHdr
+// structures. If no data is available, it will block in a poll() syscall until
+// the file descriptor becomes readable or stop is signalled (efd becomes
+// readable). Returns -1 in the latter case.
+func BlockingRecvMMsgUntilStopped(efd int, fd int, msgHdrs []MMsgHdr) (int, unix.Errno) {
+	for {
+		n, _, e := unix.RawSyscall6(unix.SYS_RECVMMSG, uintptr(fd), uintptr(unsafe.Pointer(&msgHdrs[0])), uintptr(len(msgHdrs)), unix.MSG_DONTWAIT, 0, 0)
+		if e == 0 {
+			return int(n), e
+		}
+
+		if e != 0 && e != unix.EWOULDBLOCK {
+			return 0, e
+		}
+
+		stopped, e := BlockingPollUntilStopped(efd, fd, unix.POLLIN)
+		if stopped {
+			return -1, e
+		}
+		if e != 0 && e != unix.EINTR {
+			return 0, e
+		}
+	}
+}
+
+// BlockingPollUntilStopped polls for events on fd or until a stop is signalled
+// on the event fd efd. Returns true if stopped, i.e., efd has event POLLIN.
+func BlockingPollUntilStopped(efd int, fd int, events int16) (bool, unix.Errno) {
+	pevents := [...]PollEvent{
+		{
+			FD:     int32(efd),
+			Events: unix.POLLIN,
+		},
+		{
+			FD:     int32(fd),
+			Events: events,
+		},
+	}
+	_, _, errno := unix.Syscall6(unix.SYS_PPOLL, uintptr(unsafe.Pointer(&pevents[0])), uintptr(len(pevents)), 0, 0, 0, 0)
+	if errno != 0 {
+		return pevents[0].Revents&unix.POLLIN != 0, errno
+	}
+
+	if pevents[1].Revents&unix.POLLHUP != 0 || pevents[1].Revents&unix.POLLERR != 0 {
+		errno = unix.ECONNRESET
+	}
+
+	return pevents[0].Revents&unix.POLLIN != 0, errno
+}

pkg/rawfile/rawfile_unsafe_state_autogen.go

@@ -0,0 +1,11 @@
+// automatically generated by stateify.
+
+//go:build linux && !amd64 && !arm64 && ((linux && amd64) || (linux && arm64)) && go1.18 && linux
+// +build linux
+// +build !amd64
+// +build !arm64
+// +build linux,amd64 linux,arm64
+// +build go1.18
+// +build linux
+
+package rawfile