TUN-8052: Update go to 1.21.5

Also update golang.org/x/net and google.golang.org/grpc to fix vulnerabilities,
although cloudflared is using them in a way that is not exposed to those risks

vendor/golang.org/x/sys/unix/syscall_linux.go

@@ -61,15 +61,23 @@ func FanotifyMark(fd int, flags uint, mask uint64, dirFd int, pathname string) (
 }
 
 //sys	fchmodat(dirfd int, path string, mode uint32) (err error)
+//sys	fchmodat2(dirfd int, path string, mode uint32, flags int) (err error)
 
-func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) {
-	// Linux fchmodat doesn't support the flags parameter. Mimick glibc's behavior
-	// and check the flags. Otherwise the mode would be applied to the symlink
-	// destination which is not what the user expects.
-	if flags&^AT_SYMLINK_NOFOLLOW != 0 {
-		return EINVAL
-	} else if flags&AT_SYMLINK_NOFOLLOW != 0 {
-		return EOPNOTSUPP
+func Fchmodat(dirfd int, path string, mode uint32, flags int) error {
+	// Linux fchmodat doesn't support the flags parameter, but fchmodat2 does.
+	// Try fchmodat2 if flags are specified.
+	if flags != 0 {
+		err := fchmodat2(dirfd, path, mode, flags)
+		if err == ENOSYS {
+			// fchmodat2 isn't available. If the flags are known to be valid,
+			// return EOPNOTSUPP to indicate that fchmodat doesn't support them.
+			if flags&^(AT_SYMLINK_NOFOLLOW|AT_EMPTY_PATH) != 0 {
+				return EINVAL
+			} else if flags&(AT_SYMLINK_NOFOLLOW|AT_EMPTY_PATH) != 0 {
+				return EOPNOTSUPP
+			}
+		}
+		return err
 	}
 	return fchmodat(dirfd, path, mode)
 }
@@ -417,7 +425,8 @@ func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	if n > 0 {
 		sl += _Socklen(n) + 1
 	}
-	if sa.raw.Path[0] == '@' {
+	if sa.raw.Path[0] == '@' || (sa.raw.Path[0] == 0 && sl > 3) {
+		// Check sl > 3 so we don't change unnamed socket behavior.
 		sa.raw.Path[0] = 0
 		// Don't count trailing NUL for abstract address.
 		sl--
@@ -693,10 +702,10 @@ type SockaddrALG struct {
 
 func (sa *SockaddrALG) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	// Leave room for NUL byte terminator.
-	if len(sa.Type) > 13 {
+	if len(sa.Type) > len(sa.raw.Type)-1 {
 		return nil, 0, EINVAL
 	}
-	if len(sa.Name) > 63 {
+	if len(sa.Name) > len(sa.raw.Name)-1 {
 		return nil, 0, EINVAL
 	}
 
@@ -704,17 +713,8 @@ func (sa *SockaddrALG) sockaddr() (unsafe.Pointer, _Socklen, error) {
 	sa.raw.Feat = sa.Feature
 	sa.raw.Mask = sa.Mask
 
-	typ, err := ByteSliceFromString(sa.Type)
-	if err != nil {
-		return nil, 0, err
-	}
-	name, err := ByteSliceFromString(sa.Name)
-	if err != nil {
-		return nil, 0, err
-	}
-
-	copy(sa.raw.Type[:], typ)
-	copy(sa.raw.Name[:], name)
+	copy(sa.raw.Type[:], sa.Type)
+	copy(sa.raw.Name[:], sa.Name)
 
 	return unsafe.Pointer(&sa.raw), SizeofSockaddrALG, nil
 }
@@ -1310,7 +1310,7 @@ func GetsockoptString(fd, level, opt int) (string, error) {
 			return "", err
 		}
 	}
-	return string(buf[:vallen-1]), nil
+	return ByteSliceToString(buf[:vallen]), nil
 }
 
 func GetsockoptTpacketStats(fd, level, opt int) (*TpacketStats, error) {
@@ -1885,7 +1885,7 @@ func Getpgrp() (pid int) {
 //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
 //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	pselect6(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *sigset_argpack) (n int, err error)
 //sys	read(fd int, p []byte) (n int, err error)
 //sys	Removexattr(path string, attr string) (err error)
 //sys	Renameat2(olddirfd int, oldpath string, newdirfd int, newpath string, flags uint) (err error)
@@ -1988,8 +1988,6 @@ func Signalfd(fd int, sigmask *Sigset_t, flags int) (newfd int, err error) {
 //sys	Unshare(flags int) (err error)
 //sys	write(fd int, p []byte) (n int, err error)
 //sys	exitThread(code int) (err error) = SYS_EXIT
-//sys	readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ
-//sys	writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE
 //sys	readv(fd int, iovs []Iovec) (n int, err error) = SYS_READV
 //sys	writev(fd int, iovs []Iovec) (n int, err error) = SYS_WRITEV
 //sys	preadv(fd int, iovs []Iovec, offs_l uintptr, offs_h uintptr) (n int, err error) = SYS_PREADV
@@ -2125,28 +2123,6 @@ func writevRacedetect(iovecs []Iovec, n int) {
 // mmap varies by architecture; see syscall_linux_*.go.
 //sys	munmap(addr uintptr, length uintptr) (err error)
 //sys	mremap(oldaddr uintptr, oldlength uintptr, newlength uintptr, flags int, newaddr uintptr) (xaddr uintptr, err error)
-
-var mapper = &mremapMmapper{
-	mmapper: mmapper{
-		active: make(map[*byte][]byte),
-		mmap:   mmap,
-		munmap: munmap,
-	},
-	mremap: mremap,
-}
-
-func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
-	return mapper.Mmap(fd, offset, length, prot, flags)
-}
-
-func Munmap(b []byte) (err error) {
-	return mapper.Munmap(b)
-}
-
-func Mremap(oldData []byte, newLength int, flags int) (data []byte, err error) {
-	return mapper.Mremap(oldData, newLength, flags)
-}
-
 //sys	Madvise(b []byte, advice int) (err error)
 //sys	Mprotect(b []byte, prot int) (err error)
 //sys	Mlock(b []byte) (err error)
@@ -2155,6 +2131,12 @@ func Mremap(oldData []byte, newLength int, flags int) (data []byte, err error) {
 //sys	Munlock(b []byte) (err error)
 //sys	Munlockall() (err error)
 
+const (
+	mremapFixed     = MREMAP_FIXED
+	mremapDontunmap = MREMAP_DONTUNMAP
+	mremapMaymove   = MREMAP_MAYMOVE
+)
+
 // Vmsplice splices user pages from a slice of Iovecs into a pipe specified by fd,
 // using the specified flags.
 func Vmsplice(fd int, iovs []Iovec, flags int) (int, error) {
@@ -2454,98 +2436,60 @@ func Getresgid() (rgid, egid, sgid int) {
 	return int(r), int(e), int(s)
 }
 
-/*
- * Unimplemented
- */
-// AfsSyscall
-// ArchPrctl
-// Brk
-// ClockNanosleep
-// ClockSettime
-// Clone
-// EpollCtlOld
-// EpollPwait
-// EpollWaitOld
-// Execve
-// Fork
-// Futex
-// GetKernelSyms
-// GetMempolicy
-// GetRobustList
-// GetThreadArea
-// Getpmsg
-// IoCancel
-// IoDestroy
-// IoGetevents
-// IoSetup
-// IoSubmit
-// IoprioGet
-// IoprioSet
-// KexecLoad
-// LookupDcookie
-// Mbind
-// MigratePages
-// Mincore
-// ModifyLdt
-// Mount
-// MovePages
-// MqGetsetattr
-// MqNotify
-// MqOpen
-// MqTimedreceive
-// MqTimedsend
-// MqUnlink
-// Msgctl
-// Msgget
-// Msgrcv
-// Msgsnd
-// Nfsservctl
-// Personality
-// Pselect6
-// Ptrace
-// Putpmsg
-// Quotactl
-// Readahead
-// Readv
-// RemapFilePages
-// RestartSyscall
-// RtSigaction
-// RtSigpending
-// RtSigqueueinfo
-// RtSigreturn
-// RtSigsuspend
-// RtSigtimedwait
-// SchedGetPriorityMax
-// SchedGetPriorityMin
-// SchedGetparam
-// SchedGetscheduler
-// SchedRrGetInterval
-// SchedSetparam
-// SchedYield
-// Security
-// Semctl
-// Semget
-// Semop
-// Semtimedop
-// SetMempolicy
-// SetRobustList
-// SetThreadArea
-// SetTidAddress
-// Sigaltstack
-// Swapoff
-// Swapon
-// Sysfs
-// TimerCreate
-// TimerDelete
-// TimerGetoverrun
-// TimerGettime
-// TimerSettime
-// Tkill (obsolete)
-// Tuxcall
-// Umount2
-// Uselib
-// Utimensat
-// Vfork
-// Vhangup
-// Vserver
-// _Sysctl
+// Pselect is a wrapper around the Linux pselect6 system call.
+// This version does not modify the timeout argument.
+func Pselect(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *Sigset_t) (n int, err error) {
+	// Per https://man7.org/linux/man-pages/man2/select.2.html#NOTES,
+	// The Linux pselect6() system call modifies its timeout argument.
+	// [Not modifying the argument] is the behavior required by POSIX.1-2001.
+	var mutableTimeout *Timespec
+	if timeout != nil {
+		mutableTimeout = new(Timespec)
+		*mutableTimeout = *timeout
+	}
+
+	// The final argument of the pselect6() system call is not a
+	// sigset_t * pointer, but is instead a structure
+	var kernelMask *sigset_argpack
+	if sigmask != nil {
+		wordBits := 32 << (^uintptr(0) >> 63) // see math.intSize
+
+		// A sigset stores one bit per signal,
+		// offset by 1 (because signal 0 does not exist).
+		// So the number of words needed is ⌈__C_NSIG - 1 / wordBits⌉.
+		sigsetWords := (_C__NSIG - 1 + wordBits - 1) / (wordBits)
+
+		sigsetBytes := uintptr(sigsetWords * (wordBits / 8))
+		kernelMask = &sigset_argpack{
+			ss:    sigmask,
+			ssLen: sigsetBytes,
+		}
+	}
+
+	return pselect6(nfd, r, w, e, mutableTimeout, kernelMask)
+}
+
+//sys	schedSetattr(pid int, attr *SchedAttr, flags uint) (err error)
+//sys	schedGetattr(pid int, attr *SchedAttr, size uint, flags uint) (err error)
+
+// SchedSetAttr is a wrapper for sched_setattr(2) syscall.
+// https://man7.org/linux/man-pages/man2/sched_setattr.2.html
+func SchedSetAttr(pid int, attr *SchedAttr, flags uint) error {
+	if attr == nil {
+		return EINVAL
+	}
+	attr.Size = SizeofSchedAttr
+	return schedSetattr(pid, attr, flags)
+}
+
+// SchedGetAttr is a wrapper for sched_getattr(2) syscall.
+// https://man7.org/linux/man-pages/man2/sched_getattr.2.html
+func SchedGetAttr(pid int, flags uint) (*SchedAttr, error) {
+	attr := &SchedAttr{}
+	if err := schedGetattr(pid, attr, SizeofSchedAttr, flags); err != nil {
+		return nil, err
+	}
+	return attr, nil
+}
+
+//sys	Cachestat(fd uint, crange *CachestatRange, cstat *Cachestat_t, flags uint) (err error)