From 9cbf5a3dcc71d85cd857f117d4b7189a101be9c1 Mon Sep 17 00:00:00 2001 From: Haibo Xu Date: Fri, 25 Oct 2019 03:09:59 +0000 Subject: Enable pkg/cpuid support on arm64. Fixes #1255 Signed-off-by: Haibo Xu Change-Id: I8614e6f3ee321c2989567e4e712aa8f28cc9db14 --- pkg/cpuid/cpuid_arm64.go | 461 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 461 insertions(+) create mode 100644 pkg/cpuid/cpuid_arm64.go (limited to 'pkg/cpuid/cpuid_arm64.go') diff --git a/pkg/cpuid/cpuid_arm64.go b/pkg/cpuid/cpuid_arm64.go new file mode 100644 index 000000000..6d71290c9 --- /dev/null +++ b/pkg/cpuid/cpuid_arm64.go @@ -0,0 +1,461 @@ +// 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. + +// +build arm64 + +package cpuid + +import ( + "bytes" + "encoding/binary" + "fmt" + "io/ioutil" + "strconv" + "strings" + + "gvisor.dev/gvisor/pkg/log" +) + +// ARM64 doesn't have a 'cpuid' equivalent, which means it have no architected +// discovery mechanism for hardware features available to userspace code at EL0. +// The kernel exposes the presence of these features to userspace through a set +// of flags(HWCAP/HWCAP2) bits, exposed in the auxilliary vector. +// Ref Documentation/arm64/elf_hwcaps.rst for more info. +// +// Currently, only the HWCAP bits are supported. + +const ( + // Single and double precision float point types. + ARM64FeatureFP Feature = iota + + // Advanced SIMD with single and double precision + // float point arithmetic. + ARM64FeatureASIMD + + // The generic timer is configured to generate + // events at a frequency of approximately 100KHz. + ARM64FeatureEVTSTRM + + // AES instructions(AESE/AESD/AESMC/AESIMC). + ARM64FeatureAES + + // AES instructions(PMULL/PMULL2). + ARM64FeaturePMULL + + // SHA1 instructions(SHA1C/SHA1P/SHA1M etc). + ARM64FeatureSHA1 + + // SHA2 instructions(SHA256H/SHA256H2/SHA256SU0 etc). + ARM64FeatureSHA2 + + // CRC32 instructions(CRC32B/CRC32H/CRC32W etc). + ARM64FeatureCRC32 + + // Atomic instructions(LDADD/LDCLR/LDEOR/LDSET etc). + ARM64FeatureATOMICS + + // Half precision float point arithmetic. + ARM64FeatureFPHP + + // ASIMD with half precision float point arithmetic. + ARM64FeatureASIMDHP + + // EL0 access to certain ID registers is available. + ARM64FeatureCPUID + + // SQRDMLAH and SQRDMLSH instructions implemented. + ARM64FeatureASIMDRDM + + // The FJCVTZS instruction is implemented. + ARM64FeatureJSCVT + + // The FCMLA and FCADD instructions are implemented. + ARM64FeatureFCMA + + // The LDAPRB/LDAPRH/LDAPR instructions are implemented. + ARM64FeatureLRCPC + + // DC instruction(DC CVAP) supported. + ARM64FeatureDCPOP + + // SHA3 instructions(EOR3/RAX1/XAR/BCAX) implemented. + ARM64FeatureSHA3 + + // SM3 instructions(SM3SS1/SM3TT1A/SM3TT1B) implemented. + ARM64FeatureSM3 + + // SM4 instructions(SM4E/SM4EKEY) implemented. + ARM64FeatureSM4 + + // Dot Product instructions(UDOT/SDOT) implemented. + ARM64FeatureASIMDDP + + // SHA2 instructions(SHA512H/SHA512H2/SHA512SU0) implemented. + ARM64FeatureSHA512 + + // Scalable Vector Extension implemented. + ARM64FeatureSVE + + // FMLAL and FMLSL instructions are implemented. + ARM64FeatureASIMDFHM +) + +// ELF auxiliary vector tags +const ( + _AT_NULL = 0 // End of vector + _AT_HWCAP = 16 // hardware capability bit vector + _AT_HWCAP2 = 26 // hardware capability bit vector 2 +) + +// These should not be changed after they are initialized. +var hwCap uint + +// To make emulation of /proc/cpuinfo easy, these names match the names of the +// basic features in Linux defined in arch/arm64/kernel/cpuinfo.c. +var arm64FeatureStrings = map[Feature]string{ + ARM64FeatureFP: "fp", + ARM64FeatureASIMD: "asimd", + ARM64FeatureEVTSTRM: "evtstrm", + ARM64FeatureAES: "aes", + ARM64FeaturePMULL: "pmull", + ARM64FeatureSHA1: "sha1", + ARM64FeatureSHA2: "sha2", + ARM64FeatureCRC32: "crc32", + ARM64FeatureATOMICS: "atomics", + ARM64FeatureFPHP: "fphp", + ARM64FeatureASIMDHP: "asimdhp", + ARM64FeatureCPUID: "cpuid", + ARM64FeatureASIMDRDM: "asimdrdm", + ARM64FeatureJSCVT: "jscvt", + ARM64FeatureFCMA: "fcma", + ARM64FeatureLRCPC: "lrcpc", + ARM64FeatureDCPOP: "dcpop", + ARM64FeatureSHA3: "sha3", + ARM64FeatureSM3: "sm3", + ARM64FeatureSM4: "sm4", + ARM64FeatureASIMDDP: "asimddp", + ARM64FeatureSHA512: "sha512", + ARM64FeatureSVE: "sve", + ARM64FeatureASIMDFHM: "asimdfhm", +} + +var ( + cpuFreqMHz float64 + cpuImplHex uint64 + cpuArchDec uint64 + cpuVarHex uint64 + cpuPartHex uint64 + cpuRevDec uint64 +) + +// arm64FeaturesFromString includes features from arm64FeatureStrings. +var arm64FeaturesFromString = make(map[string]Feature) + +// FeatureFromString returns the Feature associated with the given feature +// string plus a bool to indicate if it could find the feature. +func FeatureFromString(s string) (Feature, bool) { + f, b := arm64FeaturesFromString[s] + return f, b +} + +// String implements fmt.Stringer. +func (f Feature) String() string { + if s := f.flagString(); s != "" { + return s + } + + return fmt.Sprintf("", f) +} + +func (f Feature) flagString() string { + if s, ok := arm64FeatureStrings[f]; ok { + return s + } + + return "" +} + +// FeatureSet is a set of Features for a CPU. +// +// +stateify savable +type FeatureSet struct { + // Set is the set of features that are enabled in this FeatureSet. + Set map[Feature]bool + + // CPUImplementer is part of the processor signature. + CPUImplementer uint8 + + // CPUArchitecture is part of the processor signature. + CPUArchitecture uint8 + + // CPUVariant is part of the processor signature. + CPUVariant uint8 + + // CPUPartnum is part of the processor signature. + CPUPartnum uint16 + + // CPURevision is part of the processor signature. + CPURevision uint8 +} + +// CheckHostCompatible returns nil if fs is a subset of the host feature set. +// Noop on arm64. +func (fs *FeatureSet) CheckHostCompatible() error { + return nil +} + +// ExtendedStateSize returns the number of bytes needed to save the "extended +// state" for this processor and the boundary it must be aligned to. Extended +// state includes floating point(NEON) registers, and other cpu state that's not +// associated with the normal task context. +func (fs *FeatureSet) ExtendedStateSize() (size, align uint) { + // ARMv8 provide 32x128bits NEON registers. + // + // Ref arch/arm64/include/uapi/asm/ptrace.h + // struct user_fpsimd_state { + // __uint128_t vregs[32]; + // __u32 fpsr; + // __u32 fpcr; + // __u32 __reserved[2]; + // }; + return 528, 16 +} + +// HasFeature tests whether or not a feature is in the given feature set. +func (fs *FeatureSet) HasFeature(feature Feature) bool { + return fs.Set[feature] +} + +// UseXsaveopt returns true if 'fs' supports the "xsaveopt" instruction. +// Noop on arm64. +func (fs *FeatureSet) UseXsave() bool { + return false +} + +// FlagsString prints out supported CPU "flags" field in /proc/cpuinfo. +func (fs *FeatureSet) FlagsString() string { + var s []string + for f, _ := range arm64FeatureStrings { + if fs.Set[f] { + if fstr := f.flagString(); fstr != "" { + s = append(s, fstr) + } + } + } + return strings.Join(s, " ") +} + +// WriteCPUInfoTo is to generate a section of one cpu in /proc/cpuinfo. This is +// a minimal /proc/cpuinfo, and the bogomips field is simply made up. +func (fs FeatureSet) WriteCPUInfoTo(cpu uint, b *bytes.Buffer) { + fmt.Fprintf(b, "processor\t: %d\n", cpu) + fmt.Fprintf(b, "BogoMIPS\t: %.02f\n", cpuFreqMHz) // It's bogus anyway. + fmt.Fprintf(b, "Features\t\t: %s\n", fs.FlagsString()) + fmt.Fprintf(b, "CPU implementer\t: 0x%x\n", cpuImplHex) + fmt.Fprintf(b, "CPU architecture\t: %d\n", cpuArchDec) + fmt.Fprintf(b, "CPU variant\t: 0x%x\n", cpuVarHex) + fmt.Fprintf(b, "CPU part\t: 0x%x\n", cpuPartHex) + fmt.Fprintf(b, "CPU revision\t: %d\n", cpuRevDec) + fmt.Fprintln(b, "") // The /proc/cpuinfo file ends with an extra newline. +} + +// HostFeatureSet uses hwCap to get host values and construct a feature set +// that matches that of the host machine. +func HostFeatureSet() *FeatureSet { + s := make(map[Feature]bool) + + for f, _ := range arm64FeatureStrings { + if hwCap&(1< Date: Thu, 18 Jun 2020 09:02:14 -0700 Subject: Remove various uses of 'whitelist' Updates #2972 PiperOrigin-RevId: 317113059 --- pkg/bpf/interpreter_test.go | 2 +- pkg/cpuid/cpuid_arm64.go | 5 +++-- pkg/cpuid/cpuid_x86.go | 7 +++---- pkg/seccomp/seccomp_rules.go | 4 ++-- pkg/sentry/fs/filesystems.go | 14 -------------- pkg/sentry/fsimpl/host/host.go | 5 +++-- pkg/sentry/socket/hostinet/socket.go | 8 ++++---- pkg/sentry/vfs/README.md | 2 -- test/syscalls/linux/xattr.cc | 5 +++-- tools/nogo/matchers.go | 27 ++++++++++++++++----------- 10 files changed, 35 insertions(+), 44 deletions(-) (limited to 'pkg/cpuid/cpuid_arm64.go') diff --git a/pkg/bpf/interpreter_test.go b/pkg/bpf/interpreter_test.go index 547921d0a..c85d786b9 100644 --- a/pkg/bpf/interpreter_test.go +++ b/pkg/bpf/interpreter_test.go @@ -767,7 +767,7 @@ func TestSimpleFilter(t *testing.T) { expectedRet: 0, }, { - desc: "Whitelisted syscall is allowed", + desc: "Allowed syscall is indeed allowed", seccompData: seccompData{nr: 231 /* __NR_exit_group */, arch: 0xc000003e}, expectedRet: 0x7fff0000, }, diff --git a/pkg/cpuid/cpuid_arm64.go b/pkg/cpuid/cpuid_arm64.go index 08381c1c0..ac7bb6774 100644 --- a/pkg/cpuid/cpuid_arm64.go +++ b/pkg/cpuid/cpuid_arm64.go @@ -312,8 +312,9 @@ func HostFeatureSet() *FeatureSet { } } -// Reads bogomips from host /proc/cpuinfo. Must run before whitelisting. -// This value is used to create the fake /proc/cpuinfo from a FeatureSet. +// Reads bogomips from host /proc/cpuinfo. Must run before syscall filter +// installation. This value is used to create the fake /proc/cpuinfo from a +// FeatureSet. func initCPUInfo() { cpuinfob, err := ioutil.ReadFile("/proc/cpuinfo") if err != nil { diff --git a/pkg/cpuid/cpuid_x86.go b/pkg/cpuid/cpuid_x86.go index 562f8f405..17a89c00d 100644 --- a/pkg/cpuid/cpuid_x86.go +++ b/pkg/cpuid/cpuid_x86.go @@ -1057,9 +1057,9 @@ func HostFeatureSet() *FeatureSet { } } -// Reads max cpu frequency from host /proc/cpuinfo. Must run before -// whitelisting. This value is used to create the fake /proc/cpuinfo from a -// FeatureSet. +// Reads max cpu frequency from host /proc/cpuinfo. Must run before syscall +// filter installation. This value is used to create the fake /proc/cpuinfo +// from a FeatureSet. func initCPUFreq() { cpuinfob, err := ioutil.ReadFile("/proc/cpuinfo") if err != nil { @@ -1106,7 +1106,6 @@ func initFeaturesFromString() { } func init() { - // initCpuFreq must be run before whitelists are enabled. initCPUFreq() initFeaturesFromString() } diff --git a/pkg/seccomp/seccomp_rules.go b/pkg/seccomp/seccomp_rules.go index 06308cd29..a52dc1b4e 100644 --- a/pkg/seccomp/seccomp_rules.go +++ b/pkg/seccomp/seccomp_rules.go @@ -56,7 +56,7 @@ func (a AllowValue) String() (s string) { return fmt.Sprintf("%#x ", uintptr(a)) } -// Rule stores the whitelist of syscall arguments. +// Rule stores the allowed syscall arguments. // // For example: // rule := Rule { @@ -82,7 +82,7 @@ func (r Rule) String() (s string) { return } -// SyscallRules stores a map of OR'ed whitelist rules indexed by the syscall number. +// SyscallRules stores a map of OR'ed argument rules indexed by the syscall number. // If the 'Rules' is empty, we treat it as any argument is allowed. // // For example: diff --git a/pkg/sentry/fs/filesystems.go b/pkg/sentry/fs/filesystems.go index 084da2a8d..d41f30bbb 100644 --- a/pkg/sentry/fs/filesystems.go +++ b/pkg/sentry/fs/filesystems.go @@ -87,20 +87,6 @@ func RegisterFilesystem(f Filesystem) { filesystems.registered[f.Name()] = f } -// UnregisterFilesystem removes a file system from the global set. To keep the -// file system set compatible with save/restore, UnregisterFilesystem must be -// called before save/restore methods. -// -// For instance, packages may unregister their file system after it is mounted. -// This makes sense for pseudo file systems that should not be visible or -// mountable. See whitelistfs in fs/host/fs.go for one example. -func UnregisterFilesystem(name string) { - filesystems.mu.Lock() - defer filesystems.mu.Unlock() - - delete(filesystems.registered, name) -} - // FindFilesystem returns a Filesystem registered at name or (nil, false) if name // is not a file system type that can be found in /proc/filesystems. func FindFilesystem(name string) (Filesystem, bool) { diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index a3a312edb..43a173bc9 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -476,8 +476,9 @@ func (i *inode) open(ctx context.Context, d *vfs.Dentry, mnt *vfs.Mount, flags u return unixsocket.NewFileDescription(ep, ep.Type(), flags, mnt, d, &i.locks) } - // TODO(gvisor.dev/issue/1672): Whitelist specific file types here, so that - // we don't allow importing arbitrary file types without proper support. + // TODO(gvisor.dev/issue/1672): Allow only specific file types here, so + // that we don't allow importing arbitrary file types without proper + // support. if i.isTTY { fd := &TTYFileDescription{ fileDescription: fileDescription{inode: i}, diff --git a/pkg/sentry/socket/hostinet/socket.go b/pkg/sentry/socket/hostinet/socket.go index c11e82c10..a92aed2c9 100644 --- a/pkg/sentry/socket/hostinet/socket.go +++ b/pkg/sentry/socket/hostinet/socket.go @@ -324,7 +324,7 @@ func (s *socketOpsCommon) GetSockOpt(t *kernel.Task, level int, name int, outPtr return nil, syserr.ErrInvalidArgument } - // Whitelist options and constrain option length. + // Only allow known and safe options. optlen := getSockOptLen(t, level, name) switch level { case linux.SOL_IP: @@ -369,7 +369,7 @@ func (s *socketOpsCommon) GetSockOpt(t *kernel.Task, level int, name int, outPtr // SetSockOpt implements socket.Socket.SetSockOpt. func (s *socketOpsCommon) SetSockOpt(t *kernel.Task, level int, name int, opt []byte) *syserr.Error { - // Whitelist options and constrain option length. + // Only allow known and safe options. optlen := setSockOptLen(t, level, name) switch level { case linux.SOL_IP: @@ -415,7 +415,7 @@ func (s *socketOpsCommon) SetSockOpt(t *kernel.Task, level int, name int, opt [] // RecvMsg implements socket.Socket.RecvMsg. func (s *socketOpsCommon) RecvMsg(t *kernel.Task, dst usermem.IOSequence, flags int, haveDeadline bool, deadline ktime.Time, senderRequested bool, controlLen uint64) (int, int, linux.SockAddr, uint32, socket.ControlMessages, *syserr.Error) { - // Whitelist flags. + // Only allow known and safe flags. // // FIXME(jamieliu): We can't support MSG_ERRQUEUE because it uses ancillary // messages that gvisor/pkg/tcpip/transport/unix doesn't understand. Kill the @@ -537,7 +537,7 @@ func (s *socketOpsCommon) RecvMsg(t *kernel.Task, dst usermem.IOSequence, flags // SendMsg implements socket.Socket.SendMsg. func (s *socketOpsCommon) SendMsg(t *kernel.Task, src usermem.IOSequence, to []byte, flags int, haveDeadline bool, deadline ktime.Time, controlMessages socket.ControlMessages) (int, *syserr.Error) { - // Whitelist flags. + // Only allow known and safe flags. if flags&^(syscall.MSG_DONTWAIT|syscall.MSG_EOR|syscall.MSG_FASTOPEN|syscall.MSG_MORE|syscall.MSG_NOSIGNAL) != 0 { return 0, syserr.ErrInvalidArgument } diff --git a/pkg/sentry/vfs/README.md b/pkg/sentry/vfs/README.md index 66f3105bd..4b9faf2ea 100644 --- a/pkg/sentry/vfs/README.md +++ b/pkg/sentry/vfs/README.md @@ -169,8 +169,6 @@ This construction, which is essentially a type-safe analogue to Linux's - binder, which is similarly far too incomplete to use. - - whitelistfs, which we are already actively attempting to remove. - - Save/restore. For instance, it is unclear if the current implementation of the `state` package supports the inheritance pattern described above. diff --git a/test/syscalls/linux/xattr.cc b/test/syscalls/linux/xattr.cc index 3231732ec..cbcf08451 100644 --- a/test/syscalls/linux/xattr.cc +++ b/test/syscalls/linux/xattr.cc @@ -73,9 +73,10 @@ TEST_F(XattrTest, XattrLargeName) { std::string name = "user."; name += std::string(XATTR_NAME_MAX - name.length(), 'a'); - // An xattr should be whitelisted before it can be accessed--do not allow - // arbitrary xattrs to be read/written in gVisor. if (!IsRunningOnGvisor()) { + // In gVisor, access to xattrs is controlled with an explicit list of + // allowed names. This name isn't going to be configured to allow access, so + // don't test it. EXPECT_THAT(setxattr(path, name.c_str(), nullptr, 0, /*flags=*/0), SyscallSucceeds()); EXPECT_THAT(getxattr(path, name.c_str(), nullptr, 0), diff --git a/tools/nogo/matchers.go b/tools/nogo/matchers.go index 32f099925..57a250501 100644 --- a/tools/nogo/matchers.go +++ b/tools/nogo/matchers.go @@ -27,10 +27,15 @@ type matcher interface { ShouldReport(d analysis.Diagnostic, fs *token.FileSet) bool } -// pathRegexps excludes explicit paths. +// pathRegexps filters explicit paths. type pathRegexps struct { - expr []*regexp.Regexp - whitelist bool + expr []*regexp.Regexp + + // include, if true, indicates that paths matching any regexp in expr + // match. + // + // If false, paths matching no regexps in expr match. + include bool } // buildRegexps builds a list of regular expressions. @@ -49,33 +54,33 @@ func (p *pathRegexps) ShouldReport(d analysis.Diagnostic, fs *token.FileSet) boo fullPos := fs.Position(d.Pos).String() for _, path := range p.expr { if path.MatchString(fullPos) { - return p.whitelist + return p.include } } - return !p.whitelist + return !p.include } // internalExcluded excludes specific internal paths. func internalExcluded(paths ...string) *pathRegexps { return &pathRegexps{ - expr: buildRegexps(internalPrefix, paths...), - whitelist: false, + expr: buildRegexps(internalPrefix, paths...), + include: false, } } // excludedExcluded excludes specific external paths. func externalExcluded(paths ...string) *pathRegexps { return &pathRegexps{ - expr: buildRegexps(externalPrefix, paths...), - whitelist: false, + expr: buildRegexps(externalPrefix, paths...), + include: false, } } // internalMatches returns a path matcher for internal packages. func internalMatches() *pathRegexps { return &pathRegexps{ - expr: buildRegexps(internalPrefix, ".*"), - whitelist: true, + expr: buildRegexps(internalPrefix, ".*"), + include: true, } } -- cgit v1.2.3