diff options
Diffstat (limited to 'pkg/sentry/syscalls')
-rw-r--r-- | pkg/sentry/syscalls/epoll.go | 3 | ||||
-rw-r--r-- | pkg/sentry/syscalls/linux/sys_epoll.go | 27 | ||||
-rwxr-xr-x | pkg/sentry/syscalls/linux/vfs2/epoll.go | 7 | ||||
-rwxr-xr-x | pkg/sentry/syscalls/linux/vfs2/epoll_unsafe.go | 44 |
4 files changed, 9 insertions, 72 deletions
diff --git a/pkg/sentry/syscalls/epoll.go b/pkg/sentry/syscalls/epoll.go index 87dcad18b..d9fb808c0 100644 --- a/pkg/sentry/syscalls/epoll.go +++ b/pkg/sentry/syscalls/epoll.go @@ -17,6 +17,7 @@ package syscalls import ( "time" + "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/epoll" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" @@ -118,7 +119,7 @@ func RemoveEpoll(t *kernel.Task, epfd int32, fd int32) error { } // WaitEpoll implements the epoll_wait(2) linux syscall. -func WaitEpoll(t *kernel.Task, fd int32, max int, timeout int) ([]epoll.Event, error) { +func WaitEpoll(t *kernel.Task, fd int32, max int, timeout int) ([]linux.EpollEvent, error) { // Get epoll from the file descriptor. epollfile := t.GetFile(fd) if epollfile == nil { diff --git a/pkg/sentry/syscalls/linux/sys_epoll.go b/pkg/sentry/syscalls/linux/sys_epoll.go index 3ab93fbde..51bf205cf 100644 --- a/pkg/sentry/syscalls/linux/sys_epoll.go +++ b/pkg/sentry/syscalls/linux/sys_epoll.go @@ -21,7 +21,6 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/epoll" "gvisor.dev/gvisor/pkg/sentry/syscalls" "gvisor.dev/gvisor/pkg/syserror" - "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) @@ -72,7 +71,7 @@ func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc var data [2]int32 if op != linux.EPOLL_CTL_DEL { var e linux.EpollEvent - if _, err := t.CopyIn(eventAddr, &e); err != nil { + if _, err := e.CopyIn(t, eventAddr); err != nil { return 0, nil, err } @@ -105,28 +104,6 @@ func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc } } -// copyOutEvents copies epoll events from the kernel to user memory. -func copyOutEvents(t *kernel.Task, addr usermem.Addr, e []epoll.Event) error { - const itemLen = 12 - buffLen := len(e) * itemLen - if _, ok := addr.AddLength(uint64(buffLen)); !ok { - return syserror.EFAULT - } - - b := t.CopyScratchBuffer(buffLen) - for i := range e { - usermem.ByteOrder.PutUint32(b[i*itemLen:], e[i].Events) - usermem.ByteOrder.PutUint32(b[i*itemLen+4:], uint32(e[i].Data[0])) - usermem.ByteOrder.PutUint32(b[i*itemLen+8:], uint32(e[i].Data[1])) - } - - if _, err := t.CopyOutBytes(addr, b); err != nil { - return err - } - - return nil -} - // EpollWait implements the epoll_wait(2) linux syscall. func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { epfd := args[0].Int() @@ -140,7 +117,7 @@ func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys } if len(r) != 0 { - if err := copyOutEvents(t, eventsAddr, r); err != nil { + if _, err := linux.CopyEpollEventSliceOut(t, eventsAddr, r); err != nil { return 0, nil, err } } 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 -} |