1 files changed, 0 insertions, 355 deletions
diff --git a/pkg/host/features_linux.go b/pkg/host/features_linux.go
deleted file mode 100644
index 393617e45..000000000
--- a/pkg/host/features_linux.go
+++ /dev/null
@@ -1,355 +0,0 @@
-// Copyright 2015 syzkaller project authors. All rights reserved.
-// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
-
-package host
-
-import (
-	"fmt"
-	"os"
-	"os/exec"
-	"regexp"
-	"runtime"
-	"runtime/debug"
-	"strconv"
-	"syscall"
-	"unsafe"
-
-	"github.com/google/syzkaller/pkg/osutil"
-	"github.com/google/syzkaller/prog"
-	"github.com/google/syzkaller/sys/linux"
-	"golang.org/x/sys/unix"
-)
-
-func init() {
-	checkFeature[FeatureCoverage] = checkCoverage
-	checkFeature[FeatureComparisons] = checkComparisons
-	checkFeature[FeatureExtraCoverage] = checkExtraCoverage
-	checkFeature[FeatureDelayKcovMmap] = checkDelayKcovMmap
-	checkFeature[FeatureSandboxSetuid] = unconditionallyEnabled
-	checkFeature[FeatureSandboxNamespace] = checkSandboxNamespace
-	checkFeature[FeatureSandboxAndroid] = checkSandboxAndroid
-	checkFeature[FeatureFault] = checkFault
-	checkFeature[FeatureLeak] = checkLeak
-	checkFeature[FeatureNetInjection] = checkNetInjection
-	checkFeature[FeatureNetDevices] = unconditionallyEnabled
-	checkFeature[FeatureKCSAN] = checkKCSAN
-	checkFeature[FeatureDevlinkPCI] = checkDevlinkPCI
-	checkFeature[FeatureNicVF] = checkNicVF
-	checkFeature[FeatureUSBEmulation] = checkUSBEmulation
-	checkFeature[FeatureVhciInjection] = checkVhciInjection
-	checkFeature[FeatureWifiEmulation] = checkWifiEmulation
-	checkFeature[Feature802154Emulation] = check802154Emulation
-	checkFeature[FeatureSwap] = checkSwap
-}
-
-func checkCoverage() string {
-	if reason := checkDebugFS(); reason != "" {
-		return reason
-	}
-	if !osutil.IsExist("/sys/kernel/debug/kcov") {
-		return "CONFIG_KCOV is not enabled"
-	}
-	if err := osutil.IsAccessible("/sys/kernel/debug/kcov"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkComparisons() (reason string) {
-	return checkCoverageFeature(FeatureComparisons)
-}
-
-func checkExtraCoverage() (reason string) {
-	return checkCoverageFeature(FeatureExtraCoverage)
-}
-
-func checkDelayKcovMmap() string {
-	// The kcov implementation in Linux (currently) does not adequately handle subsequent
-	// mmap invocations on the same descriptor. When that problem is fixed, we want
-	// syzkaller to differentiate between distributions as this allows to noticeably speed
-	// up fuzzing.
-	return checkCoverageFeature(FeatureDelayKcovMmap)
-}
-
-func kcovTestMmap(fd int, coverSize uintptr) (reason string) {
-	mem, err := syscall.Mmap(fd, 0, int(coverSize*unsafe.Sizeof(uintptr(0))),
-		syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED)
-	if err != nil {
-		return fmt.Sprintf("KCOV mmap failed: %v", err)
-	}
-	defer func() {
-		if err := syscall.Munmap(mem); err != nil {
-			reason = fmt.Sprintf("munmap failed: %v", err)
-		}
-	}()
-	// Now the tricky part - mmap may say it has succeeded, but the memory is
-	// in fact not allocated.
-	// We try to access it. If go does not panic, everything is fine.
-	prevValue := debug.SetPanicOnFault(true)
-	defer debug.SetPanicOnFault(prevValue)
-	defer func() {
-		if r := recover(); r != nil {
-			reason = "mmap returned an invalid pointer"
-		}
-	}()
-	mem[0] = 0
-	return ""
-}
-
-func checkCoverageFeature(feature int) (reason string) {
-	if reason = checkDebugFS(); reason != "" {
-		return reason
-	}
-	// TODO(dvyukov): this should run under target arch.
-	// E.g. KCOV ioctls were initially not supported on 386 (missing compat_ioctl),
-	// and a 386 executor won't be able to use them, but an amd64 fuzzer will be.
-	fd, err := syscall.Open("/sys/kernel/debug/kcov", syscall.O_RDWR, 0)
-	if err != nil {
-		return "CONFIG_KCOV is not enabled"
-	}
-	defer syscall.Close(fd)
-	// Trigger host target lazy initialization, it will fill linux.KCOV_INIT_TRACE.
-	// It's all wrong and needs to be refactored.
-	if _, err := prog.GetTarget(runtime.GOOS, runtime.GOARCH); err != nil {
-		return fmt.Sprintf("failed to get target: %v", err)
-	}
-	coverSize := uintptr(64 << 10)
-	_, _, errno := syscall.Syscall(
-		syscall.SYS_IOCTL, uintptr(fd), linux.KCOV_INIT_TRACE, coverSize)
-	if errno != 0 {
-		return fmt.Sprintf("ioctl(KCOV_INIT_TRACE) failed: %v", errno)
-	}
-	if reason = kcovTestMmap(fd, coverSize); reason != "" {
-		return reason
-	}
-	disableKcov := func() {
-		_, _, errno = syscall.Syscall(syscall.SYS_IOCTL, uintptr(fd), linux.KCOV_DISABLE, 0)
-		if errno != 0 {
-			reason = fmt.Sprintf("ioctl(KCOV_DISABLE) failed: %v", errno)
-		}
-	}
-	switch feature {
-	case FeatureComparisons:
-		_, _, errno = syscall.Syscall(syscall.SYS_IOCTL,
-			uintptr(fd), linux.KCOV_ENABLE, linux.KCOV_TRACE_CMP)
-		if errno != 0 {
-			if errno == 524 { // ENOTSUPP
-				return "CONFIG_KCOV_ENABLE_COMPARISONS is not enabled"
-			}
-			return fmt.Sprintf("ioctl(KCOV_TRACE_CMP) failed: %v", errno)
-		}
-		defer disableKcov()
-	case FeatureExtraCoverage:
-		arg := KcovRemoteArg{
-			TraceMode:    uint32(linux.KCOV_TRACE_PC),
-			AreaSize:     uint32(coverSize * unsafe.Sizeof(uintptr(0))),
-			NumHandles:   0,
-			CommonHandle: 0,
-		}
-		_, _, errno = syscall.Syscall(syscall.SYS_IOCTL,
-			uintptr(fd), linux.KCOV_REMOTE_ENABLE, uintptr(unsafe.Pointer(&arg)))
-		if errno != 0 {
-			if errno == 25 { // ENOTTY
-				return "extra coverage is not supported by the kernel"
-			}
-			return fmt.Sprintf("ioctl(KCOV_REMOTE_ENABLE) failed: %v", errno)
-		}
-		defer disableKcov()
-	case FeatureDelayKcovMmap:
-		if reason = kcovTestMmap(fd, coverSize); reason != "" {
-			return reason
-		}
-	default:
-		panic("unknown feature in checkCoverageFeature")
-	}
-	return ""
-}
-
-type KcovRemoteArg struct {
-	TraceMode    uint32
-	AreaSize     uint32
-	NumHandles   uint32
-	_            uint32
-	CommonHandle uint64
-	// Handles []uint64 goes here.
-}
-
-func checkFault() string {
-	if err := osutil.IsAccessible("/proc/self/make-it-fail"); err != nil {
-		return "CONFIG_FAULT_INJECTION is not enabled"
-	}
-	if err := osutil.IsAccessible("/proc/thread-self/fail-nth"); err != nil {
-		return "kernel does not have systematic fault injection support"
-	}
-	if reason := checkDebugFS(); reason != "" {
-		return reason
-	}
-	if err := osutil.IsAccessible("/sys/kernel/debug/failslab/ignore-gfp-wait"); err != nil {
-		return "CONFIG_FAULT_INJECTION_DEBUG_FS or CONFIG_FAILSLAB are not enabled"
-	}
-	return ""
-}
-
-func checkLeak() string {
-	if reason := checkDebugFS(); reason != "" {
-		return reason
-	}
-	fd, err := syscall.Open("/sys/kernel/debug/kmemleak", syscall.O_RDWR, 0)
-	if err != nil {
-		return "CONFIG_DEBUG_KMEMLEAK is not enabled"
-	}
-	defer syscall.Close(fd)
-	if _, err := syscall.Write(fd, []byte("scan=off")); err != nil {
-		if err == syscall.EBUSY {
-			return "KMEMLEAK disabled: increase CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE or unset CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF"
-		}
-		return fmt.Sprintf("/sys/kernel/debug/kmemleak write failed: %v", err)
-	}
-	return ""
-}
-
-func checkSandboxNamespace() string {
-	if err := osutil.IsAccessible("/proc/self/ns/user"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkSandboxAndroid() string {
-	if err := osutil.IsAccessible("/sys/fs/selinux/policy"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkNetInjection() string {
-	if err := osutil.IsAccessible("/dev/net/tun"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkUSBEmulation() string {
-	if err := osutil.IsAccessible("/dev/raw-gadget"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkVhciInjection() string {
-	if err := osutil.IsAccessible("/dev/vhci"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkDebugFS() string {
-	if err := osutil.IsAccessible("/sys/kernel/debug"); err != nil {
-		return "debugfs is not enabled or not mounted"
-	}
-	return ""
-}
-
-func checkKCSAN() string {
-	if err := osutil.IsAccessible("/sys/kernel/debug/kcsan"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkDevlinkPCI() string {
-	if err := osutil.IsAccessible("/sys/bus/pci/devices/0000:00:10.0/"); err != nil {
-		return "PCI device 0000:00:10.0 is not available"
-	}
-	if err := osutil.IsAccessible("/proc/self/ns/net"); err != nil {
-		// Initialize_devlink_pci in executor fails w/o this.
-		return "/proc/self/ns/net does not exist"
-	}
-	return ""
-}
-
-func checkNicVF() string {
-	if err := osutil.IsAccessible("/sys/bus/pci/devices/0000:00:11.0/"); err != nil {
-		return "PCI device 0000:00:11.0 is not available"
-	}
-	return ""
-}
-
-func checkWifiEmulation() string {
-	if err := osutil.IsAccessible("/sys/class/mac80211_hwsim/"); err != nil {
-		return err.Error()
-	}
-	// We use HWSIM_ATTR_PERM_ADDR which was added in 4.17.
-	return requireKernel(4, 17)
-}
-
-func check802154Emulation() string {
-	if err := osutil.IsAccessible("/sys/bus/platform/devices/mac802154_hwsim"); err != nil {
-		return err.Error()
-	}
-	return ""
-}
-
-func checkSwap() string {
-	if err := osutil.IsAccessible("/proc/swaps"); err != nil {
-		return err.Error()
-	}
-	if _, err := exec.LookPath("mkswap"); err != nil {
-		return "mkswap is not available"
-	}
-	// We use fallocate in syz-executor, so let's check if the filesystem supports it.
-	// /tmp might not always be the best choice for this
-	// (on some systems, a different filesystem might be used for /tmp).
-	dir, err := os.UserHomeDir()
-	if err != nil {
-		return fmt.Sprintf("failed to get home dir: %v", err)
-	}
-	f, err := os.CreateTemp(dir, "any-file")
-	if err != nil {
-		return fmt.Sprintf("failed to create temp file: %v", err)
-	}
-	defer os.Remove(f.Name())
-	err = syscall.Fallocate(int(f.Fd()), unix.FALLOC_FL_ZERO_RANGE, 0, 2048)
-	if err != nil {
-		return fmt.Sprintf("fallocate failed: %v", err)
-	}
-	return ""
-}
-
-func requireKernel(x, y int) string {
-	info := new(unix.Utsname)
-	if err := unix.Uname(info); err != nil {
-		return fmt.Sprintf("uname failed: %v", err)
-	}
-	ver := string(info.Release[:])
-	if ok, bad := matchKernelVersion(ver, x, y); bad {
-		return fmt.Sprintf("failed to parse kernel version (%v)", ver)
-	} else if !ok {
-		return fmt.Sprintf("kernel %v.%v required (have %v)", x, y, ver)
-	}
-	return ""
-}
-
-func matchKernelVersion(ver string, x, y int) (bool, bool) {
-	match := kernelVersionRe.FindStringSubmatch(ver)
-	if match == nil {
-		return false, true
-	}
-	major, err := strconv.Atoi(match[1])
-	if err != nil {
-		return false, true
-	}
-	if major <= 0 || major > 999 {
-		return false, true
-	}
-	minor, err := strconv.Atoi(match[2])
-	if err != nil {
-		return false, true
-	}
-	if minor <= 0 || minor > 999 {
-		return false, true
-	}
-	return major*1000+minor >= x*1000+y, false
-}
-
-var kernelVersionRe = regexp.MustCompile(`^([0-9]+)\.([0-9]+)`)