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/abi/linux/epoll.go

@@ -0,0 +1,58 @@
+// 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.
+
+package linux
+
+// Event masks.
+const (
+	EPOLLIN     = 0x1
+	EPOLLPRI    = 0x2
+	EPOLLOUT    = 0x4
+	EPOLLERR    = 0x8
+	EPOLLHUP    = 0x10
+	EPOLLRDNORM = 0x40
+	EPOLLRDBAND = 0x80
+	EPOLLWRNORM = 0x100
+	EPOLLWRBAND = 0x200
+	EPOLLMSG    = 0x400
+	EPOLLRDHUP  = 0x2000
+)
+
+// Per-file descriptor flags.
+const (
+	EPOLLEXCLUSIVE = 1 << 28
+	EPOLLWAKEUP    = 1 << 29
+	EPOLLONESHOT   = 1 << 30
+	EPOLLET        = 1 << 31
+
+	// EP_PRIVATE_BITS is fs/eventpoll.c:EP_PRIVATE_BITS, the set of all bits
+	// in an epoll event mask that correspond to flags rather than I/O events.
+	EP_PRIVATE_BITS = EPOLLEXCLUSIVE | EPOLLWAKEUP | EPOLLONESHOT | EPOLLET
+)
+
+// Operation flags.
+const (
+	EPOLL_CLOEXEC  = 0x80000
+	EPOLL_NONBLOCK = 0x800
+)
+
+// Control operations.
+const (
+	EPOLL_CTL_ADD = 0x1
+	EPOLL_CTL_DEL = 0x2
+	EPOLL_CTL_MOD = 0x3
+)
+
+// SizeOfEpollEvent is the size of EpollEvent struct.
+var SizeOfEpollEvent = (*EpollEvent)(nil).SizeBytes()