update dependencies

1 files changed, 230 insertions, 175 deletions

diff --git a/vendor/golang.org/x/sys/unix/syscall_linux.go b/vendor/golang.org/x/sys/unix/syscall_linux.go
index 41b91fd..ecb0f27 100644
--- a/vendor/golang.org/x/sys/unix/syscall_linux.go
+++ b/vendor/golang.org/x/sys/unix/syscall_linux.go
@@ -13,8 +13,8 @@ package unix
 
 import (
 	"encoding/binary"
-	"runtime"
 	"syscall"
+	"time"
 	"unsafe"
 )
 
@@ -38,6 +38,13 @@ func Creat(path string, mode uint32) (fd int, err error) {
 	return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode)
 }
 
+func EpollCreate(size int) (fd int, err error) {
+	if size <= 0 {
+		return -1, EINVAL
+	}
+	return EpollCreate1(0)
+}
+
 //sys	FanotifyInit(flags uint, event_f_flags uint) (fd int, err error)
 //sys	fanotifyMark(fd int, flags uint, mask uint64, dirFd int, pathname *byte) (err error)
 
@@ -66,11 +73,22 @@ func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) {
 	return fchmodat(dirfd, path, mode)
 }
 
-//sys	ioctl(fd int, req uint, arg uintptr) (err error)
+func InotifyInit() (fd int, err error) {
+	return InotifyInit1(0)
+}
 
-// ioctl itself should not be exposed directly, but additional get/set
-// functions for specific types are permissible.
-// These are defined in ioctl.go and ioctl_linux.go.
+//sys	ioctl(fd int, req uint, arg uintptr) (err error) = SYS_IOCTL
+//sys	ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) = SYS_IOCTL
+
+// ioctl itself should not be exposed directly, but additional get/set functions
+// for specific types are permissible. These are defined in ioctl.go and
+// ioctl_linux.go.
+//
+// The third argument to ioctl is often a pointer but sometimes an integer.
+// Callers should use ioctlPtr when the third argument is a pointer and ioctl
+// when the third argument is an integer.
+//
+// TODO: some existing code incorrectly uses ioctl when it should use ioctlPtr.
 
 //sys	Linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)
 
@@ -102,6 +120,25 @@ func Openat2(dirfd int, path string, how *OpenHow) (fd int, err error) {
 	return openat2(dirfd, path, how, SizeofOpenHow)
 }
 
+func Pipe(p []int) error {
+	return Pipe2(p, 0)
+}
+
+//sysnb	pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) error {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err := pipe2(&pp, flags)
+	if err == nil {
+		p[0] = int(pp[0])
+		p[1] = int(pp[1])
+	}
+	return err
+}
+
 //sys	ppoll(fds *PollFd, nfds int, timeout *Timespec, sigmask *Sigset_t) (n int, err error)
 
 func Ppoll(fds []PollFd, timeout *Timespec, sigmask *Sigset_t) (n int, err error) {
@@ -111,6 +148,15 @@ func Ppoll(fds []PollFd, timeout *Timespec, sigmask *Sigset_t) (n int, err error
 	return ppoll(&fds[0], len(fds), timeout, sigmask)
 }
 
+func Poll(fds []PollFd, timeout int) (n int, err error) {
+	var ts *Timespec
+	if timeout >= 0 {
+		ts = new(Timespec)
+		*ts = NsecToTimespec(int64(timeout) * 1e6)
+	}
+	return Ppoll(fds, ts, nil)
+}
+
 //sys	Readlinkat(dirfd int, path string, buf []byte) (n int, err error)
 
 func Readlink(path string, buf []byte) (n int, err error) {
@@ -161,27 +207,7 @@ func Utimes(path string, tv []Timeval) error {
 //sys	utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)
 
 func UtimesNano(path string, ts []Timespec) error {
-	if ts == nil {
-		err := utimensat(AT_FDCWD, path, nil, 0)
-		if err != ENOSYS {
-			return err
-		}
-		return utimes(path, nil)
-	}
-	if len(ts) != 2 {
-		return EINVAL
-	}
-	err := utimensat(AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
-	if err != ENOSYS {
-		return err
-	}
-	// If the utimensat syscall isn't available (utimensat was added to Linux
-	// in 2.6.22, Released, 8 July 2007) then fall back to utimes
-	var tv [2]Timeval
-	for i := 0; i < 2; i++ {
-		tv[i] = NsecToTimeval(TimespecToNsec(ts[i]))
-	}
-	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
+	return UtimesNanoAt(AT_FDCWD, path, ts, 0)
 }
 
 func UtimesNanoAt(dirfd int, path string, ts []Timespec, flags int) error {
@@ -224,6 +250,13 @@ func Getwd() (wd string, err error) {
 	if n < 1 || n > len(buf) || buf[n-1] != 0 {
 		return "", EINVAL
 	}
+	// In some cases, Linux can return a path that starts with the
+	// "(unreachable)" prefix, which can potentially be a valid relative
+	// path. To work around that, return ENOENT if path is not absolute.
+	if buf[0] != '/' {
+		return "", ENOENT
+	}
+
 	return string(buf[0 : n-1]), nil
 }
 
@@ -333,6 +366,8 @@ func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int,
 	return
 }
 
+//sys	Waitid(idType int, id int, info *Siginfo, options int, rusage *Rusage) (err error)
+
 func Mkfifo(path string, mode uint32) error {
 	return Mknod(path, mode|S_IFIFO, 0)
 }
@@ -349,9 +384,7 @@ func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
 	p[0] = byte(sa.Port >> 8)
 	p[1] = byte(sa.Port)
-	for i := 0; i < len(sa.Addr); i++ {
-		sa.raw.Addr[i] = sa.Addr[i]
-	}
+	sa.raw.Addr = sa.Addr
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil
 }
 
@@ -364,9 +397,7 @@ func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	p[0] = byte(sa.Port >> 8)
 	p[1] = byte(sa.Port)
 	sa.raw.Scope_id = sa.ZoneId
-	for i := 0; i < len(sa.Addr); i++ {
-		sa.raw.Addr[i] = sa.Addr[i]
-	}
+	sa.raw.Addr = sa.Addr
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil
 }
 
@@ -415,9 +446,7 @@ func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	sa.raw.Hatype = sa.Hatype
 	sa.raw.Pkttype = sa.Pkttype
 	sa.raw.Halen = sa.Halen
-	for i := 0; i < len(sa.Addr); i++ {
-		sa.raw.Addr[i] = sa.Addr[i]
-	}
+	sa.raw.Addr = sa.Addr
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil
 }
 
@@ -483,24 +512,24 @@ func (sa *SockaddrL2) sockaddr() (unsafe.Pointer, _Socklen, error) {
 //
 // Server example:
 //
-//      fd, _ := Socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM)
-//      _ = unix.Bind(fd, &unix.SockaddrRFCOMM{
-//      	Channel: 1,
-//      	Addr:    [6]uint8{0, 0, 0, 0, 0, 0}, // BDADDR_ANY or 00:00:00:00:00:00
-//      })
-//      _ = Listen(fd, 1)
-//      nfd, sa, _ := Accept(fd)
-//      fmt.Printf("conn addr=%v fd=%d", sa.(*unix.SockaddrRFCOMM).Addr, nfd)
-//      Read(nfd, buf)
+//	fd, _ := Socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM)
+//	_ = unix.Bind(fd, &unix.SockaddrRFCOMM{
+//		Channel: 1,
+//		Addr:    [6]uint8{0, 0, 0, 0, 0, 0}, // BDADDR_ANY or 00:00:00:00:00:00
+//	})
+//	_ = Listen(fd, 1)
+//	nfd, sa, _ := Accept(fd)
+//	fmt.Printf("conn addr=%v fd=%d", sa.(*unix.SockaddrRFCOMM).Addr, nfd)
+//	Read(nfd, buf)
 //
 // Client example:
 //
-//      fd, _ := Socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM)
-//      _ = Connect(fd, &SockaddrRFCOMM{
-//      	Channel: 1,
-//      	Addr:    [6]byte{0x11, 0x22, 0x33, 0xaa, 0xbb, 0xcc}, // CC:BB:AA:33:22:11
-//      })
-//      Write(fd, []byte(`hello`))
+//	fd, _ := Socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM)
+//	_ = Connect(fd, &SockaddrRFCOMM{
+//		Channel: 1,
+//		Addr:    [6]byte{0x11, 0x22, 0x33, 0xaa, 0xbb, 0xcc}, // CC:BB:AA:33:22:11
+//	})
+//	Write(fd, []byte(`hello`))
 type SockaddrRFCOMM struct {
 	// Addr represents a bluetooth address, byte ordering is little-endian.
 	Addr [6]uint8
@@ -527,12 +556,12 @@ func (sa *SockaddrRFCOMM) sockaddr() (unsafe.Pointer, _Socklen, error) {
 // The SockaddrCAN struct must be bound to the socket file descriptor
 // using Bind before the CAN socket can be used.
 //
-//      // Read one raw CAN frame
-//      fd, _ := Socket(AF_CAN, SOCK_RAW, CAN_RAW)
-//      addr := &SockaddrCAN{Ifindex: index}
-//      Bind(fd, addr)
-//      frame := make([]byte, 16)
-//      Read(fd, frame)
+//	// Read one raw CAN frame
+//	fd, _ := Socket(AF_CAN, SOCK_RAW, CAN_RAW)
+//	addr := &SockaddrCAN{Ifindex: index}
+//	Bind(fd, addr)
+//	frame := make([]byte, 16)
+//	Read(fd, frame)
 //
 // The full SocketCAN documentation can be found in the linux kernel
 // archives at: https://www.kernel.org/doc/Documentation/networking/can.txt
@@ -603,13 +632,13 @@ func (sa *SockaddrCANJ1939) sockaddr() (unsafe.Pointer, _Socklen, error) {
 // Here is an example of using an AF_ALG socket with SHA1 hashing.
 // The initial socket setup process is as follows:
 //
-//      // Open a socket to perform SHA1 hashing.
-//      fd, _ := unix.Socket(unix.AF_ALG, unix.SOCK_SEQPACKET, 0)
-//      addr := &unix.SockaddrALG{Type: "hash", Name: "sha1"}
-//      unix.Bind(fd, addr)
-//      // Note: unix.Accept does not work at this time; must invoke accept()
-//      // manually using unix.Syscall.
-//      hashfd, _, _ := unix.Syscall(unix.SYS_ACCEPT, uintptr(fd), 0, 0)
+//	// Open a socket to perform SHA1 hashing.
+//	fd, _ := unix.Socket(unix.AF_ALG, unix.SOCK_SEQPACKET, 0)
+//	addr := &unix.SockaddrALG{Type: "hash", Name: "sha1"}
+//	unix.Bind(fd, addr)
+//	// Note: unix.Accept does not work at this time; must invoke accept()
+//	// manually using unix.Syscall.
+//	hashfd, _, _ := unix.Syscall(unix.SYS_ACCEPT, uintptr(fd), 0, 0)
 //
 // Once a file descriptor has been returned from Accept, it may be used to
 // perform SHA1 hashing. The descriptor is not safe for concurrent use, but
@@ -618,39 +647,39 @@ func (sa *SockaddrCANJ1939) sockaddr() (unsafe.Pointer, _Socklen, error) {
 // When hashing a small byte slice or string, a single Write and Read may
 // be used:
 //
-//      // Assume hashfd is already configured using the setup process.
-//      hash := os.NewFile(hashfd, "sha1")
-//      // Hash an input string and read the results. Each Write discards
-//      // previous hash state. Read always reads the current state.
-//      b := make([]byte, 20)
-//      for i := 0; i < 2; i++ {
-//          io.WriteString(hash, "Hello, world.")
-//          hash.Read(b)
-//          fmt.Println(hex.EncodeToString(b))
-//      }
-//      // Output:
-//      // 2ae01472317d1935a84797ec1983ae243fc6aa28
-//      // 2ae01472317d1935a84797ec1983ae243fc6aa28
+//	// Assume hashfd is already configured using the setup process.
+//	hash := os.NewFile(hashfd, "sha1")
+//	// Hash an input string and read the results. Each Write discards
+//	// previous hash state. Read always reads the current state.
+//	b := make([]byte, 20)
+//	for i := 0; i < 2; i++ {
+//	    io.WriteString(hash, "Hello, world.")
+//	    hash.Read(b)
+//	    fmt.Println(hex.EncodeToString(b))
+//	}
+//	// Output:
+//	// 2ae01472317d1935a84797ec1983ae243fc6aa28
+//	// 2ae01472317d1935a84797ec1983ae243fc6aa28
 //
 // For hashing larger byte slices, or byte streams such as those read from
 // a file or socket, use Sendto with MSG_MORE to instruct the kernel to update
 // the hash digest instead of creating a new one for a given chunk and finalizing it.
 //
-//      // Assume hashfd and addr are already configured using the setup process.
-//      hash := os.NewFile(hashfd, "sha1")
-//      // Hash the contents of a file.
-//      f, _ := os.Open("/tmp/linux-4.10-rc7.tar.xz")
-//      b := make([]byte, 4096)
-//      for {
-//          n, err := f.Read(b)
-//          if err == io.EOF {
-//              break
-//          }
-//          unix.Sendto(hashfd, b[:n], unix.MSG_MORE, addr)
-//      }
-//      hash.Read(b)
-//      fmt.Println(hex.EncodeToString(b))
-//      // Output: 85cdcad0c06eef66f805ecce353bec9accbeecc5
+//	// Assume hashfd and addr are already configured using the setup process.
+//	hash := os.NewFile(hashfd, "sha1")
+//	// Hash the contents of a file.
+//	f, _ := os.Open("/tmp/linux-4.10-rc7.tar.xz")
+//	b := make([]byte, 4096)
+//	for {
+//	    n, err := f.Read(b)
+//	    if err == io.EOF {
+//	        break
+//	    }
+//	    unix.Sendto(hashfd, b[:n], unix.MSG_MORE, addr)
+//	}
+//	hash.Read(b)
+//	fmt.Println(hex.EncodeToString(b))
+//	// Output: 85cdcad0c06eef66f805ecce353bec9accbeecc5
 //
 // For more information, see: http://www.chronox.de/crypto-API/crypto/userspace-if.html.
 type SockaddrALG struct {
@@ -832,12 +861,10 @@ func (sa *SockaddrTIPC) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	if sa.Addr == nil {
 		return nil, 0, EINVAL
 	}
-
 	sa.raw.Family = AF_TIPC
 	sa.raw.Scope = int8(sa.Scope)
 	sa.raw.Addrtype = sa.Addr.tipcAddrtype()
 	sa.raw.Addr = sa.Addr.tipcAddr()
-
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrTIPC, nil
 }
 
@@ -851,9 +878,7 @@ type SockaddrL2TPIP struct {
 func (sa *SockaddrL2TPIP) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	sa.raw.Family = AF_INET
 	sa.raw.Conn_id = sa.ConnId
-	for i := 0; i < len(sa.Addr); i++ {
-		sa.raw.Addr[i] = sa.Addr[i]
-	}
+	sa.raw.Addr = sa.Addr
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrL2TPIP, nil
 }
 
@@ -869,9 +894,7 @@ func (sa *SockaddrL2TPIP6) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	sa.raw.Family = AF_INET6
 	sa.raw.Conn_id = sa.ConnId
 	sa.raw.Scope_id = sa.ZoneId
-	for i := 0; i < len(sa.Addr); i++ {
-		sa.raw.Addr[i] = sa.Addr[i]
-	}
+	sa.raw.Addr = sa.Addr
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrL2TPIP6, nil
 }
 
@@ -967,9 +990,7 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 		sa.Hatype = pp.Hatype
 		sa.Pkttype = pp.Pkttype
 		sa.Halen = pp.Halen
-		for i := 0; i < len(sa.Addr); i++ {
-			sa.Addr[i] = pp.Addr[i]
-		}
+		sa.Addr = pp.Addr
 		return sa, nil
 
 	case AF_UNIX:
@@ -1008,18 +1029,14 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 			pp := (*RawSockaddrL2TPIP)(unsafe.Pointer(rsa))
 			sa := new(SockaddrL2TPIP)
 			sa.ConnId = pp.Conn_id
-			for i := 0; i < len(sa.Addr); i++ {
-				sa.Addr[i] = pp.Addr[i]
-			}
+			sa.Addr = pp.Addr
 			return sa, nil
 		default:
 			pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
 			sa := new(SockaddrInet4)
 			p := (*[2]byte)(unsafe.Pointer(&pp.Port))
 			sa.Port = int(p[0])<<8 + int(p[1])
-			for i := 0; i < len(sa.Addr); i++ {
-				sa.Addr[i] = pp.Addr[i]
-			}
+			sa.Addr = pp.Addr
 			return sa, nil
 		}
 
@@ -1035,9 +1052,7 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 			sa := new(SockaddrL2TPIP6)
 			sa.ConnId = pp.Conn_id
 			sa.ZoneId = pp.Scope_id
-			for i := 0; i < len(sa.Addr); i++ {
-				sa.Addr[i] = pp.Addr[i]
-			}
+			sa.Addr = pp.Addr
 			return sa, nil
 		default:
 			pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
@@ -1045,9 +1060,7 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 			p := (*[2]byte)(unsafe.Pointer(&pp.Port))
 			sa.Port = int(p[0])<<8 + int(p[1])
 			sa.ZoneId = pp.Scope_id
-			for i := 0; i < len(sa.Addr); i++ {
-				sa.Addr[i] = pp.Addr[i]
-			}
+			sa.Addr = pp.Addr
 			return sa, nil
 		}
 
@@ -1222,11 +1235,7 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 func Accept(fd int) (nfd int, sa Sockaddr, err error) {
 	var rsa RawSockaddrAny
 	var len _Socklen = SizeofSockaddrAny
-	// Try accept4 first for Android, then try accept for kernel older than 2.6.28
 	nfd, err = accept4(fd, &rsa, &len, 0)
-	if err == ENOSYS {
-		nfd, err = accept(fd, &rsa, &len)
-	}
 	if err != nil {
 		return
 	}
@@ -1348,6 +1357,13 @@ func SetsockoptTpacketReq3(fd, level, opt int, tp *TpacketReq3) error {
 	return setsockopt(fd, level, opt, unsafe.Pointer(tp), unsafe.Sizeof(*tp))
 }
 
+func SetsockoptTCPRepairOpt(fd, level, opt int, o []TCPRepairOpt) (err error) {
+	if len(o) == 0 {
+		return EINVAL
+	}
+	return setsockopt(fd, level, opt, unsafe.Pointer(&o[0]), uintptr(SizeofTCPRepairOpt*len(o)))
+}
+
 // Keyctl Commands (http://man7.org/linux/man-pages/man2/keyctl.2.html)
 
 // KeyctlInt calls keyctl commands in which each argument is an int.
@@ -1483,19 +1499,13 @@ func KeyctlRestrictKeyring(ringid int, keyType string, restriction string) error
 //sys	keyctlRestrictKeyringByType(cmd int, arg2 int, keyType string, restriction string) (err error) = SYS_KEYCTL
 //sys	keyctlRestrictKeyring(cmd int, arg2 int) (err error) = SYS_KEYCTL
 
-func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
+func recvmsgRaw(fd int, iov []Iovec, oob []byte, flags int, rsa *RawSockaddrAny) (n, oobn int, recvflags int, err error) {
 	var msg Msghdr
-	var rsa RawSockaddrAny
-	msg.Name = (*byte)(unsafe.Pointer(&rsa))
+	msg.Name = (*byte)(unsafe.Pointer(rsa))
 	msg.Namelen = uint32(SizeofSockaddrAny)
-	var iov Iovec
-	if len(p) > 0 {
-		iov.Base = &p[0]
-		iov.SetLen(len(p))
-	}
 	var dummy byte
 	if len(oob) > 0 {
-		if len(p) == 0 {
+		if emptyIovecs(iov) {
 			var sockType int
 			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
 			if err != nil {
@@ -1503,53 +1513,36 @@ func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from
 			}
 			// receive at least one normal byte
 			if sockType != SOCK_DGRAM {
-				iov.Base = &dummy
-				iov.SetLen(1)
+				var iova [1]Iovec
+				iova[0].Base = &dummy
+				iova[0].SetLen(1)
+				iov = iova[:]
 			}
 		}
 		msg.Control = &oob[0]
 		msg.SetControllen(len(oob))
 	}
-	msg.Iov = &iov
-	msg.Iovlen = 1
+	if len(iov) > 0 {
+		msg.Iov = &iov[0]
+		msg.SetIovlen(len(iov))
+	}
 	if n, err = recvmsg(fd, &msg, flags); err != nil {
 		return
 	}
 	oobn = int(msg.Controllen)
 	recvflags = int(msg.Flags)
-	// source address is only specified if the socket is unconnected
-	if rsa.Addr.Family != AF_UNSPEC {
-		from, err = anyToSockaddr(fd, &rsa)
-	}
-	return
-}
-
-func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
-	_, err = SendmsgN(fd, p, oob, to, flags)
 	return
 }
 
-func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
-	var ptr unsafe.Pointer
-	var salen _Socklen
-	if to != nil {
-		var err error
-		ptr, salen, err = to.sockaddr()
-		if err != nil {
-			return 0, err
-		}
-	}
+func sendmsgN(fd int, iov []Iovec, oob []byte, ptr unsafe.Pointer, salen _Socklen, flags int) (n int, err error) {
 	var msg Msghdr
 	msg.Name = (*byte)(ptr)
 	msg.Namelen = uint32(salen)
-	var iov Iovec
-	if len(p) > 0 {
-		iov.Base = &p[0]
-		iov.SetLen(len(p))
-	}
 	var dummy byte
+	var empty bool
 	if len(oob) > 0 {
-		if len(p) == 0 {
+		empty = emptyIovecs(iov)
+		if empty {
 			var sockType int
 			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
 			if err != nil {
@@ -1557,19 +1550,22 @@ func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error)
 			}
 			// send at least one normal byte
 			if sockType != SOCK_DGRAM {
-				iov.Base = &dummy
-				iov.SetLen(1)
+				var iova [1]Iovec
+				iova[0].Base = &dummy
+				iova[0].SetLen(1)
 			}
 		}
 		msg.Control = &oob[0]
 		msg.SetControllen(len(oob))
 	}
-	msg.Iov = &iov
-	msg.Iovlen = 1
+	if len(iov) > 0 {
+		msg.Iov = &iov[0]
+		msg.SetIovlen(len(iov))
+	}
 	if n, err = sendmsg(fd, &msg, flags); err != nil {
 		return 0, err
 	}
-	if len(oob) > 0 && len(p) == 0 {
+	if len(oob) > 0 && empty {
 		n = 0
 	}
 	return n, nil
@@ -1771,6 +1767,16 @@ func Mount(source string, target string, fstype string, flags uintptr, data stri
 	return mount(source, target, fstype, flags, datap)
 }
 
+//sys	mountSetattr(dirfd int, pathname string, flags uint, attr *MountAttr, size uintptr) (err error) = SYS_MOUNT_SETATTR
+
+// MountSetattr is a wrapper for mount_setattr(2).
+// https://man7.org/linux/man-pages/man2/mount_setattr.2.html
+//
+// Requires kernel >= 5.12.
+func MountSetattr(dirfd int, pathname string, flags uint, attr *MountAttr) error {
+	return mountSetattr(dirfd, pathname, flags, attr, unsafe.Sizeof(*attr))
+}
+
 func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
 	if raceenabled {
 		raceReleaseMerge(unsafe.Pointer(&ioSync))
@@ -1802,11 +1808,7 @@ func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err e
 //sys	Dup(oldfd int) (fd int, err error)
 
 func Dup2(oldfd, newfd int) error {
-	// Android O and newer blocks dup2; riscv and arm64 don't implement dup2.
-	if runtime.GOOS == "android" || runtime.GOARCH == "riscv64" || runtime.GOARCH == "arm64" {
-		return Dup3(oldfd, newfd, 0)
-	}
-	return dup2(oldfd, newfd)
+	return Dup3(oldfd, newfd, 0)
 }
 
 //sys	Dup3(oldfd int, newfd int, flags int) (err error)
@@ -1826,6 +1828,9 @@ func Dup2(oldfd, newfd int) error {
 //sys	Fremovexattr(fd int, attr string) (err error)
 //sys	Fsetxattr(fd int, attr string, dest []byte, flags int) (err error)
 //sys	Fsync(fd int) (err error)
+//sys	Fsmount(fd int, flags int, mountAttrs int) (fsfd int, err error)
+//sys	Fsopen(fsName string, flags int) (fd int, err error)
+//sys	Fspick(dirfd int, pathName string, flags int) (fd int, err error)
 //sys	Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
 //sysnb	Getpgid(pid int) (pgid int, err error)
 
@@ -1856,10 +1861,12 @@ func Getpgrp() (pid int) {
 //sys	MemfdCreate(name string, flags int) (fd int, err error)
 //sys	Mkdirat(dirfd int, path string, mode uint32) (err error)
 //sys	Mknodat(dirfd int, path string, mode uint32, dev int) (err error)
+//sys	MoveMount(fromDirfd int, fromPathName string, toDirfd int, toPathName string, flags int) (err error)
 //sys	Nanosleep(time *Timespec, leftover *Timespec) (err error)
+//sys	OpenTree(dfd int, fileName string, flags uint) (r int, err error)
 //sys	PerfEventOpen(attr *PerfEventAttr, pid int, cpu int, groupFd int, flags int) (fd int, err error)
 //sys	PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT
-//sysnb	prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64
+//sysnb	Prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64
 //sys	Prctl(option int, arg2 uintptr, arg3 uintptr, arg4 uintptr, arg5 uintptr) (err error)
 //sys	Pselect(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *Sigset_t) (n int, err error) = SYS_PSELECT6
 //sys	read(fd int, p []byte) (n int, err error)
@@ -2181,7 +2188,7 @@ func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 			gid = Getgid()
 		}
 
-		if uint32(gid) == st.Gid || isGroupMember(gid) {
+		if uint32(gid) == st.Gid || isGroupMember(int(st.Gid)) {
 			fmode = (st.Mode >> 3) & 7
 		} else {
 			fmode = st.Mode & 7
@@ -2294,11 +2301,65 @@ type RemoteIovec struct {
 //sys	ProcessVMReadv(pid int, localIov []Iovec, remoteIov []RemoteIovec, flags uint) (n int, err error) = SYS_PROCESS_VM_READV
 //sys	ProcessVMWritev(pid int, localIov []Iovec, remoteIov []RemoteIovec, flags uint) (n int, err error) = SYS_PROCESS_VM_WRITEV
 
+//sys	PidfdOpen(pid int, flags int) (fd int, err error) = SYS_PIDFD_OPEN
+//sys	PidfdGetfd(pidfd int, targetfd int, flags int) (fd int, err error) = SYS_PIDFD_GETFD
+//sys	PidfdSendSignal(pidfd int, sig Signal, info *Siginfo, flags int) (err error) = SYS_PIDFD_SEND_SIGNAL
+
+//sys	shmat(id int, addr uintptr, flag int) (ret uintptr, err error)
+//sys	shmctl(id int, cmd int, buf *SysvShmDesc) (result int, err error)
+//sys	shmdt(addr uintptr) (err error)
+//sys	shmget(key int, size int, flag int) (id int, err error)
+
+//sys	getitimer(which int, currValue *Itimerval) (err error)
+//sys	setitimer(which int, newValue *Itimerval, oldValue *Itimerval) (err error)
+
+// MakeItimerval creates an Itimerval from interval and value durations.
+func MakeItimerval(interval, value time.Duration) Itimerval {
+	return Itimerval{
+		Interval: NsecToTimeval(interval.Nanoseconds()),
+		Value:    NsecToTimeval(value.Nanoseconds()),
+	}
+}
+
+// A value which may be passed to the which parameter for Getitimer and
+// Setitimer.
+type ItimerWhich int
+
+// Possible which values for Getitimer and Setitimer.
+const (
+	ItimerReal    ItimerWhich = ITIMER_REAL
+	ItimerVirtual ItimerWhich = ITIMER_VIRTUAL
+	ItimerProf    ItimerWhich = ITIMER_PROF
+)
+
+// Getitimer wraps getitimer(2) to return the current value of the timer
+// specified by which.
+func Getitimer(which ItimerWhich) (Itimerval, error) {
+	var it Itimerval
+	if err := getitimer(int(which), &it); err != nil {
+		return Itimerval{}, err
+	}
+
+	return it, nil
+}
+
+// Setitimer wraps setitimer(2) to arm or disarm the timer specified by which.
+// It returns the previous value of the timer.
+//
+// If the Itimerval argument is the zero value, the timer will be disarmed.
+func Setitimer(which ItimerWhich, it Itimerval) (Itimerval, error) {
+	var prev Itimerval
+	if err := setitimer(int(which), &it, &prev); err != nil {
+		return Itimerval{}, err
+	}
+
+	return prev, nil
+}
+
 /*
  * Unimplemented
  */
 // AfsSyscall
-// Alarm
 // ArchPrctl
 // Brk
 // ClockNanosleep
@@ -2314,7 +2375,6 @@ type RemoteIovec struct {
 // GetMempolicy
 // GetRobustList
 // GetThreadArea
-// Getitimer
 // Getpmsg
 // IoCancel
 // IoDestroy
@@ -2375,10 +2435,6 @@ type RemoteIovec struct {
 // SetRobustList
 // SetThreadArea
 // SetTidAddress
-// Shmat
-// Shmctl
-// Shmdt
-// Shmget
 // Sigaltstack
 // Swapoff
 // Swapon
@@ -2396,5 +2452,4 @@ type RemoteIovec struct {
 // Vfork
 // Vhangup
 // Vserver
-// Waitid
 // _Sysctl