Merge release-20200323.0-226-g93dd471 (automated)

2 files changed, 5 insertions, 46 deletions

diff --git a/pkg/sentry/syscalls/linux/vfs2/epoll.go b/pkg/sentry/syscalls/linux/vfs2/epoll.go
index 5a938cee2..34c90ae3e 100755
--- a/pkg/sentry/syscalls/linux/vfs2/epoll.go
+++ b/pkg/sentry/syscalls/linux/vfs2/epoll.go
@@ -28,6 +28,8 @@ import (
 	"gvisor.dev/gvisor/pkg/waiter"
 )
 
+var sizeofEpollEvent = (*linux.EpollEvent)(nil).SizeBytes()
+
 // EpollCreate1 implements Linux syscall epoll_create1(2).
 func EpollCreate1(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
 	flags := args[0].Int()
@@ -124,7 +126,7 @@ func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys
 	maxEvents := int(args[2].Int())
 	timeout := int(args[3].Int())
 
-	const _EP_MAX_EVENTS = math.MaxInt32 / sizeofEpollEvent // Linux: fs/eventpoll.c:EP_MAX_EVENTS
+	var _EP_MAX_EVENTS = math.MaxInt32 / sizeofEpollEvent // Linux: fs/eventpoll.c:EP_MAX_EVENTS
 	if maxEvents <= 0 || maxEvents > _EP_MAX_EVENTS {
 		return 0, nil, syserror.EINVAL
 	}
@@ -157,7 +159,8 @@ func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys
 		maxEvents -= n
 		if n != 0 {
 			// Copy what we read out.
-			copiedEvents, err := copyOutEvents(t, eventsAddr, events[:n])
+			copiedBytes, err := linux.CopyEpollEventSliceOut(t, eventsAddr, events[:n])
+			copiedEvents := copiedBytes / sizeofEpollEvent // rounded down
 			eventsAddr += usermem.Addr(copiedEvents * sizeofEpollEvent)
 			total += copiedEvents
 			if err != nil {
diff --git a/pkg/sentry/syscalls/linux/vfs2/epoll_unsafe.go b/pkg/sentry/syscalls/linux/vfs2/epoll_unsafe.go
deleted file mode 100755
index 825f325bf..000000000
--- a/pkg/sentry/syscalls/linux/vfs2/epoll_unsafe.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// 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 vfs2
-
-import (
-	"reflect"
-	"runtime"
-	"unsafe"
-
-	"gvisor.dev/gvisor/pkg/abi/linux"
-	"gvisor.dev/gvisor/pkg/gohacks"
-	"gvisor.dev/gvisor/pkg/sentry/kernel"
-	"gvisor.dev/gvisor/pkg/usermem"
-)
-
-const sizeofEpollEvent = int(unsafe.Sizeof(linux.EpollEvent{}))
-
-func copyOutEvents(t *kernel.Task, addr usermem.Addr, events []linux.EpollEvent) (int, error) {
-	if len(events) == 0 {
-		return 0, nil
-	}
-	// Cast events to a byte slice for copying.
-	var eventBytes []byte
-	eventBytesHdr := (*reflect.SliceHeader)(unsafe.Pointer(&eventBytes))
-	eventBytesHdr.Data = uintptr(gohacks.Noescape(unsafe.Pointer(&events[0])))
-	eventBytesHdr.Len = len(events) * sizeofEpollEvent
-	eventBytesHdr.Cap = len(events) * sizeofEpollEvent
-	copiedBytes, err := t.CopyOutBytes(addr, eventBytes)
-	runtime.KeepAlive(events)
-	copiedEvents := copiedBytes / sizeofEpollEvent // rounded down
-	return copiedEvents, err
-}