diff options
| -rw-r--r-- | pkg/flipcall/BUILD | 1 | ||||
| -rw-r--r-- | pkg/flipcall/flipcall.go | 2 | ||||
| -rw-r--r-- | pkg/flipcall/packet_window_mmap.go | 25 |
3 files changed, 27 insertions, 1 deletions
diff --git a/pkg/flipcall/BUILD b/pkg/flipcall/BUILD index 9c5ad500b..aa8e4e1f3 100644 --- a/pkg/flipcall/BUILD +++ b/pkg/flipcall/BUILD @@ -11,6 +11,7 @@ go_library( "futex_linux.go", "io.go", "packet_window_allocator.go", + "packet_window_mmap.go", ], visibility = ["//visibility:public"], deps = [ diff --git a/pkg/flipcall/flipcall.go b/pkg/flipcall/flipcall.go index 3cdb576e1..ec742c091 100644 --- a/pkg/flipcall/flipcall.go +++ b/pkg/flipcall/flipcall.go @@ -95,7 +95,7 @@ func (ep *Endpoint) Init(side EndpointSide, pwd PacketWindowDescriptor, opts ... if pwd.Length > math.MaxUint32 { return fmt.Errorf("packet window size (%d) exceeds maximum (%d)", pwd.Length, math.MaxUint32) } - m, _, e := syscall.RawSyscall6(syscall.SYS_MMAP, 0, uintptr(pwd.Length), syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED, uintptr(pwd.FD), uintptr(pwd.Offset)) + m, e := packetWindowMmap(pwd) if e != 0 { return fmt.Errorf("failed to mmap packet window: %v", e) } diff --git a/pkg/flipcall/packet_window_mmap.go b/pkg/flipcall/packet_window_mmap.go new file mode 100644 index 000000000..869183b11 --- /dev/null +++ b/pkg/flipcall/packet_window_mmap.go @@ -0,0 +1,25 @@ +// Copyright 2020 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 flipcall + +import ( + "syscall" +) + +// Return a memory mapping of the pwd in memory that can be shared outside the sandbox. +func packetWindowMmap(pwd PacketWindowDescriptor) (uintptr, syscall.Errno) { + m, _, err := syscall.RawSyscall6(syscall.SYS_MMAP, 0, uintptr(pwd.Length), syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED, uintptr(pwd.FD), uintptr(pwd.Offset)) + return m, err +} |