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-rw-r--r--pkg/sentry/arch/BUILD34
-rw-r--r--pkg/sentry/arch/arch.go11
-rw-r--r--pkg/sentry/arch/arch_aarch64.go317
-rw-r--r--pkg/sentry/arch/arch_amd64.go23
-rw-r--r--pkg/sentry/arch/arch_amd64.s7
-rw-r--r--pkg/sentry/arch/arch_arm64.go284
-rw-r--r--pkg/sentry/arch/arch_state_x86.go50
-rw-r--r--pkg/sentry/arch/arch_x86.go50
-rw-r--r--pkg/sentry/arch/arch_x86_impl.go41
-rw-r--r--pkg/sentry/arch/auxv.go2
-rw-r--r--pkg/sentry/arch/registers.proto37
-rw-r--r--pkg/sentry/arch/signal.go253
-rw-r--r--pkg/sentry/arch/signal_act.go4
-rw-r--r--pkg/sentry/arch/signal_amd64.go234
-rw-r--r--pkg/sentry/arch/signal_arm64.go159
-rw-r--r--pkg/sentry/arch/signal_stack.go7
-rw-r--r--pkg/sentry/arch/stack.go7
-rw-r--r--pkg/sentry/arch/syscalls_amd64.go7
-rw-r--r--pkg/sentry/arch/syscalls_arm64.go81
19 files changed, 1257 insertions, 351 deletions
diff --git a/pkg/sentry/arch/BUILD b/pkg/sentry/arch/BUILD
index 18c73cc24..901e0f320 100644
--- a/pkg/sentry/arch/BUILD
+++ b/pkg/sentry/arch/BUILD
@@ -1,6 +1,4 @@
-load("@io_bazel_rules_go//proto:def.bzl", "go_proto_library")
-load("@rules_cc//cc:defs.bzl", "cc_proto_library")
-load("//tools/go_stateify:defs.bzl", "go_library")
+load("//tools:defs.bzl", "go_library", "proto_library")
package(licenses = ["notice"])
@@ -9,48 +7,42 @@ go_library(
srcs = [
"aligned.go",
"arch.go",
+ "arch_aarch64.go",
"arch_amd64.go",
"arch_amd64.s",
+ "arch_arm64.go",
"arch_state_x86.go",
"arch_x86.go",
+ "arch_x86_impl.go",
"auxv.go",
+ "signal.go",
"signal_act.go",
"signal_amd64.go",
+ "signal_arm64.go",
"signal_info.go",
"signal_stack.go",
"stack.go",
"syscalls_amd64.go",
+ "syscalls_arm64.go",
],
- importpath = "gvisor.dev/gvisor/pkg/sentry/arch",
+ marshal = True,
visibility = ["//:sandbox"],
deps = [
":registers_go_proto",
"//pkg/abi/linux",
- "//pkg/binary",
+ "//pkg/context",
"//pkg/cpuid",
"//pkg/log",
- "//pkg/sentry/context",
"//pkg/sentry/limits",
- "//pkg/sentry/usermem",
+ "//pkg/sync",
"//pkg/syserror",
+ "//pkg/usermem",
+ "//tools/go_marshal/marshal",
],
)
proto_library(
- name = "registers_proto",
+ name = "registers",
srcs = ["registers.proto"],
visibility = ["//visibility:public"],
)
-
-cc_proto_library(
- name = "registers_cc_proto",
- visibility = ["//visibility:public"],
- deps = [":registers_proto"],
-)
-
-go_proto_library(
- name = "registers_go_proto",
- importpath = "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto",
- proto = ":registers_proto",
- visibility = ["//visibility:public"],
-)
diff --git a/pkg/sentry/arch/arch.go b/pkg/sentry/arch/arch.go
index 498ca4669..a903d031c 100644
--- a/pkg/sentry/arch/arch.go
+++ b/pkg/sentry/arch/arch.go
@@ -24,7 +24,7 @@ import (
"gvisor.dev/gvisor/pkg/cpuid"
"gvisor.dev/gvisor/pkg/log"
"gvisor.dev/gvisor/pkg/sentry/limits"
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/usermem"
)
// Arch describes an architecture.
@@ -88,6 +88,9 @@ type Context interface {
// SyscallNo returns the syscall number.
SyscallNo() uintptr
+ // SyscallSaveOrig save orignal register value.
+ SyscallSaveOrig()
+
// SyscallArgs returns the syscall arguments in an array.
SyscallArgs() SyscallArguments
@@ -125,9 +128,9 @@ type Context interface {
// SetTLS sets the current TLS pointer. Returns false if value is invalid.
SetTLS(value uintptr) bool
- // SetRSEQInterruptedIP sets the register that contains the old IP when a
- // restartable sequence is interrupted.
- SetRSEQInterruptedIP(value uintptr)
+ // SetOldRSeqInterruptedIP sets the register that contains the old IP
+ // when an "old rseq" restartable sequence is interrupted.
+ SetOldRSeqInterruptedIP(value uintptr)
// StateData returns a pointer to underlying architecture state.
StateData() *State
diff --git a/pkg/sentry/arch/arch_aarch64.go b/pkg/sentry/arch/arch_aarch64.go
new file mode 100644
index 000000000..529980267
--- /dev/null
+++ b/pkg/sentry/arch/arch_aarch64.go
@@ -0,0 +1,317 @@
+// 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 arch
+
+import (
+ "encoding/binary"
+ "fmt"
+ "io"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/cpuid"
+ "gvisor.dev/gvisor/pkg/log"
+ rpb "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto"
+ "gvisor.dev/gvisor/pkg/syserror"
+)
+
+// Registers represents the CPU registers for this architecture.
+type Registers = linux.PtraceRegs
+
+const (
+ // SyscallWidth is the width of insturctions.
+ SyscallWidth = 4
+
+ // fpsimdMagic is the magic number which is used in fpsimd_context.
+ fpsimdMagic = 0x46508001
+
+ // fpsimdContextSize is the size of fpsimd_context.
+ fpsimdContextSize = 0x210
+)
+
+// ARMTrapFlag is the mask for the trap flag.
+const ARMTrapFlag = uint64(1) << 21
+
+// aarch64FPState is aarch64 floating point state.
+type aarch64FPState []byte
+
+// initAarch64FPState sets up initial state.
+func initAarch64FPState(data aarch64FPState) {
+ binary.LittleEndian.PutUint32(data, fpsimdMagic)
+ binary.LittleEndian.PutUint32(data[4:], fpsimdContextSize)
+}
+
+func newAarch64FPStateSlice() []byte {
+ return alignedBytes(4096, 16)[:fpsimdContextSize]
+}
+
+// newAarch64FPState returns an initialized floating point state.
+//
+// The returned state is large enough to store all floating point state
+// supported by host, even if the app won't use much of it due to a restricted
+// FeatureSet.
+func newAarch64FPState() aarch64FPState {
+ f := aarch64FPState(newAarch64FPStateSlice())
+ initAarch64FPState(f)
+ return f
+}
+
+// fork creates and returns an identical copy of the aarch64 floating point state.
+func (f aarch64FPState) fork() aarch64FPState {
+ n := aarch64FPState(newAarch64FPStateSlice())
+ copy(n, f)
+ return n
+}
+
+// FloatingPointData returns the raw data pointer.
+func (f aarch64FPState) FloatingPointData() *FloatingPointData {
+ return (*FloatingPointData)(&f[0])
+}
+
+// NewFloatingPointData returns a new floating point data blob.
+//
+// This is primarily for use in tests.
+func NewFloatingPointData() *FloatingPointData {
+ return (*FloatingPointData)(&(newAarch64FPState()[0]))
+}
+
+// State contains the common architecture bits for aarch64 (the build tag of this
+// file ensures it's only built on aarch64).
+type State struct {
+ // The system registers.
+ Regs Registers
+
+ // Our floating point state.
+ aarch64FPState `state:"wait"`
+
+ // TLS pointer
+ TPValue uint64
+
+ // FeatureSet is a pointer to the currently active feature set.
+ FeatureSet *cpuid.FeatureSet
+
+ // OrigR0 stores the value of register R0.
+ OrigR0 uint64
+}
+
+// Proto returns a protobuf representation of the system registers in State.
+func (s State) Proto() *rpb.Registers {
+ regs := &rpb.ARM64Registers{
+ R0: s.Regs.Regs[0],
+ R1: s.Regs.Regs[1],
+ R2: s.Regs.Regs[2],
+ R3: s.Regs.Regs[3],
+ R4: s.Regs.Regs[4],
+ R5: s.Regs.Regs[5],
+ R6: s.Regs.Regs[6],
+ R7: s.Regs.Regs[7],
+ R8: s.Regs.Regs[8],
+ R9: s.Regs.Regs[9],
+ R10: s.Regs.Regs[10],
+ R11: s.Regs.Regs[11],
+ R12: s.Regs.Regs[12],
+ R13: s.Regs.Regs[13],
+ R14: s.Regs.Regs[14],
+ R15: s.Regs.Regs[15],
+ R16: s.Regs.Regs[16],
+ R17: s.Regs.Regs[17],
+ R18: s.Regs.Regs[18],
+ R19: s.Regs.Regs[19],
+ R20: s.Regs.Regs[20],
+ R21: s.Regs.Regs[21],
+ R22: s.Regs.Regs[22],
+ R23: s.Regs.Regs[23],
+ R24: s.Regs.Regs[24],
+ R25: s.Regs.Regs[25],
+ R26: s.Regs.Regs[26],
+ R27: s.Regs.Regs[27],
+ R28: s.Regs.Regs[28],
+ R29: s.Regs.Regs[29],
+ R30: s.Regs.Regs[30],
+ Sp: s.Regs.Sp,
+ Pc: s.Regs.Pc,
+ Pstate: s.Regs.Pstate,
+ }
+ return &rpb.Registers{Arch: &rpb.Registers_Arm64{Arm64: regs}}
+}
+
+// Fork creates and returns an identical copy of the state.
+func (s *State) Fork() State {
+ return State{
+ Regs: s.Regs,
+ aarch64FPState: s.aarch64FPState.fork(),
+ TPValue: s.TPValue,
+ FeatureSet: s.FeatureSet,
+ OrigR0: s.OrigR0,
+ }
+}
+
+// StateData implements Context.StateData.
+func (s *State) StateData() *State {
+ return s
+}
+
+// CPUIDEmulate emulates a cpuid instruction.
+func (s *State) CPUIDEmulate(l log.Logger) {
+ // TODO(gvisor.dev/issue/1255): cpuid is not supported.
+}
+
+// SingleStep implements Context.SingleStep.
+func (s *State) SingleStep() bool {
+ return false
+}
+
+// SetSingleStep enables single stepping.
+func (s *State) SetSingleStep() {
+ // Set the trap flag.
+ // TODO(gvisor.dev/issue/1239): ptrace single-step is not supported.
+}
+
+// ClearSingleStep enables single stepping.
+func (s *State) ClearSingleStep() {
+ // Clear the trap flag.
+ // TODO(gvisor.dev/issue/1239): ptrace single-step is not supported.
+}
+
+// RegisterMap returns a map of all registers.
+func (s *State) RegisterMap() (map[string]uintptr, error) {
+ return map[string]uintptr{
+ "R0": uintptr(s.Regs.Regs[0]),
+ "R1": uintptr(s.Regs.Regs[1]),
+ "R2": uintptr(s.Regs.Regs[2]),
+ "R3": uintptr(s.Regs.Regs[3]),
+ "R4": uintptr(s.Regs.Regs[4]),
+ "R5": uintptr(s.Regs.Regs[5]),
+ "R6": uintptr(s.Regs.Regs[6]),
+ "R7": uintptr(s.Regs.Regs[7]),
+ "R8": uintptr(s.Regs.Regs[8]),
+ "R9": uintptr(s.Regs.Regs[9]),
+ "R10": uintptr(s.Regs.Regs[10]),
+ "R11": uintptr(s.Regs.Regs[11]),
+ "R12": uintptr(s.Regs.Regs[12]),
+ "R13": uintptr(s.Regs.Regs[13]),
+ "R14": uintptr(s.Regs.Regs[14]),
+ "R15": uintptr(s.Regs.Regs[15]),
+ "R16": uintptr(s.Regs.Regs[16]),
+ "R17": uintptr(s.Regs.Regs[17]),
+ "R18": uintptr(s.Regs.Regs[18]),
+ "R19": uintptr(s.Regs.Regs[19]),
+ "R20": uintptr(s.Regs.Regs[20]),
+ "R21": uintptr(s.Regs.Regs[21]),
+ "R22": uintptr(s.Regs.Regs[22]),
+ "R23": uintptr(s.Regs.Regs[23]),
+ "R24": uintptr(s.Regs.Regs[24]),
+ "R25": uintptr(s.Regs.Regs[25]),
+ "R26": uintptr(s.Regs.Regs[26]),
+ "R27": uintptr(s.Regs.Regs[27]),
+ "R28": uintptr(s.Regs.Regs[28]),
+ "R29": uintptr(s.Regs.Regs[29]),
+ "R30": uintptr(s.Regs.Regs[30]),
+ "Sp": uintptr(s.Regs.Sp),
+ "Pc": uintptr(s.Regs.Pc),
+ "Pstate": uintptr(s.Regs.Pstate),
+ }, nil
+}
+
+// PtraceGetRegs implements Context.PtraceGetRegs.
+func (s *State) PtraceGetRegs(dst io.Writer) (int, error) {
+ regs := s.ptraceGetRegs()
+ n, err := regs.WriteTo(dst)
+ return int(n), err
+}
+
+func (s *State) ptraceGetRegs() Registers {
+ return s.Regs
+}
+
+var registersSize = (*Registers)(nil).SizeBytes()
+
+// PtraceSetRegs implements Context.PtraceSetRegs.
+func (s *State) PtraceSetRegs(src io.Reader) (int, error) {
+ var regs Registers
+ buf := make([]byte, registersSize)
+ if _, err := io.ReadFull(src, buf); err != nil {
+ return 0, err
+ }
+ regs.UnmarshalUnsafe(buf)
+ s.Regs = regs
+ return registersSize, nil
+}
+
+// PtraceGetFPRegs implements Context.PtraceGetFPRegs.
+func (s *State) PtraceGetFPRegs(dst io.Writer) (int, error) {
+ // TODO(gvisor.dev/issue/1238): floating-point is not supported.
+ return 0, nil
+}
+
+// PtraceSetFPRegs implements Context.PtraceSetFPRegs.
+func (s *State) PtraceSetFPRegs(src io.Reader) (int, error) {
+ // TODO(gvisor.dev/issue/1238): floating-point is not supported.
+ return 0, nil
+}
+
+// Register sets defined in include/uapi/linux/elf.h.
+const (
+ _NT_PRSTATUS = 1
+ _NT_PRFPREG = 2
+ _NT_ARM_TLS = 0x401
+)
+
+// PtraceGetRegSet implements Context.PtraceGetRegSet.
+func (s *State) PtraceGetRegSet(regset uintptr, dst io.Writer, maxlen int) (int, error) {
+ switch regset {
+ case _NT_PRSTATUS:
+ if maxlen < ptraceRegsSize {
+ return 0, syserror.EFAULT
+ }
+ return s.PtraceGetRegs(dst)
+ default:
+ return 0, syserror.EINVAL
+ }
+}
+
+// PtraceSetRegSet implements Context.PtraceSetRegSet.
+func (s *State) PtraceSetRegSet(regset uintptr, src io.Reader, maxlen int) (int, error) {
+ switch regset {
+ case _NT_PRSTATUS:
+ if maxlen < ptraceRegsSize {
+ return 0, syserror.EFAULT
+ }
+ return s.PtraceSetRegs(src)
+ default:
+ return 0, syserror.EINVAL
+ }
+}
+
+// FullRestore indicates whether a full restore is required.
+func (s *State) FullRestore() bool {
+ return false
+}
+
+// New returns a new architecture context.
+func New(arch Arch, fs *cpuid.FeatureSet) Context {
+ switch arch {
+ case ARM64:
+ return &context64{
+ State{
+ aarch64FPState: newAarch64FPState(),
+ FeatureSet: fs,
+ },
+ []aarch64FPState(nil),
+ }
+ }
+ panic(fmt.Sprintf("unknown architecture %v", arch))
+}
diff --git a/pkg/sentry/arch/arch_amd64.go b/pkg/sentry/arch/arch_amd64.go
index 9e7db8b30..3b3a0a272 100644
--- a/pkg/sentry/arch/arch_amd64.go
+++ b/pkg/sentry/arch/arch_amd64.go
@@ -22,10 +22,9 @@ import (
"math/rand"
"syscall"
- "gvisor.dev/gvisor/pkg/binary"
"gvisor.dev/gvisor/pkg/cpuid"
"gvisor.dev/gvisor/pkg/sentry/limits"
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/usermem"
)
// Host specifies the host architecture.
@@ -174,8 +173,8 @@ func (c *context64) SetTLS(value uintptr) bool {
return true
}
-// SetRSEQInterruptedIP implements Context.SetRSEQInterruptedIP.
-func (c *context64) SetRSEQInterruptedIP(value uintptr) {
+// SetOldRSeqInterruptedIP implements Context.SetOldRSeqInterruptedIP.
+func (c *context64) SetOldRSeqInterruptedIP(value uintptr) {
c.Regs.R10 = uint64(value)
}
@@ -301,11 +300,13 @@ func (c *context64) PtracePeekUser(addr uintptr) (interface{}, error) {
// PTRACE_PEEKUSER and PTRACE_POKEUSER are only effective on regs and
// u_debugreg, returning 0 or silently no-oping for other fields
// respectively.
- if addr < uintptr(ptraceRegsSize) {
- buf := binary.Marshal(nil, usermem.ByteOrder, c.ptraceGetRegs())
+ if addr < uintptr(registersSize) {
+ regs := c.ptraceGetRegs()
+ buf := make([]byte, regs.SizeBytes())
+ regs.MarshalUnsafe(buf)
return c.Native(uintptr(usermem.ByteOrder.Uint64(buf[addr:]))), nil
}
- // TODO(b/34088053): debug registers
+ // Note: x86 debug registers are missing.
return c.Native(0), nil
}
@@ -314,12 +315,14 @@ func (c *context64) PtracePokeUser(addr, data uintptr) error {
if addr&7 != 0 || addr >= userStructSize {
return syscall.EIO
}
- if addr < uintptr(ptraceRegsSize) {
- buf := binary.Marshal(nil, usermem.ByteOrder, c.ptraceGetRegs())
+ if addr < uintptr(registersSize) {
+ regs := c.ptraceGetRegs()
+ buf := make([]byte, regs.SizeBytes())
+ regs.MarshalUnsafe(buf)
usermem.ByteOrder.PutUint64(buf[addr:], uint64(data))
_, err := c.PtraceSetRegs(bytes.NewBuffer(buf))
return err
}
- // TODO(b/34088053): debug registers
+ // Note: x86 debug registers are missing.
return nil
}
diff --git a/pkg/sentry/arch/arch_amd64.s b/pkg/sentry/arch/arch_amd64.s
index bd61402cf..6c10336e7 100644
--- a/pkg/sentry/arch/arch_amd64.s
+++ b/pkg/sentry/arch/arch_amd64.s
@@ -26,10 +26,11 @@
//
// func initX86FPState(data *FloatingPointData, useXsave bool)
//
-// We need to clear out and initialize an empty fp state area since the sentry
-// may have left sensitive information in the floating point registers.
+// We need to clear out and initialize an empty fp state area since the sentry,
+// or any previous loader, may have left sensitive information in the floating
+// point registers.
//
-// Preconditions: data is zeroed
+// Preconditions: data is zeroed.
TEXT ·initX86FPState(SB), $24-16
// Save MXCSR (callee-save)
STMXCSR mxcsr-8(SP)
diff --git a/pkg/sentry/arch/arch_arm64.go b/pkg/sentry/arch/arch_arm64.go
new file mode 100644
index 000000000..ada7ac7b8
--- /dev/null
+++ b/pkg/sentry/arch/arch_arm64.go
@@ -0,0 +1,284 @@
+// 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 arch
+
+import (
+ "fmt"
+ "math/rand"
+ "syscall"
+
+ "gvisor.dev/gvisor/pkg/cpuid"
+ "gvisor.dev/gvisor/pkg/sentry/limits"
+ "gvisor.dev/gvisor/pkg/usermem"
+)
+
+// Host specifies the host architecture.
+const Host = ARM64
+
+// These constants come directly from Linux.
+const (
+ // maxAddr64 is the maximum userspace address. It is TASK_SIZE in Linux
+ // for a 64-bit process.
+ maxAddr64 usermem.Addr = (1 << 48)
+
+ // maxStackRand64 is the maximum randomization to apply to the stack.
+ // It is defined by arch/arm64/mm/mmap.c:(STACK_RND_MASK << PAGE_SHIFT) in Linux.
+ maxStackRand64 = 0x3ffff << 12 // 16 GB
+
+ // maxMmapRand64 is the maximum randomization to apply to the mmap
+ // layout. It is defined by arch/arm64/mm/mmap.c:arch_mmap_rnd in Linux.
+ maxMmapRand64 = (1 << 33) * usermem.PageSize
+
+ // minGap64 is the minimum gap to leave at the top of the address space
+ // for the stack. It is defined by arch/arm64/mm/mmap.c:MIN_GAP in Linux.
+ minGap64 = (128 << 20) + maxStackRand64
+
+ // preferredPIELoadAddr is the standard Linux position-independent
+ // executable base load address. It is ELF_ET_DYN_BASE in Linux.
+ //
+ // The Platform {Min,Max}UserAddress() may preclude loading at this
+ // address. See other preferredFoo comments below.
+ preferredPIELoadAddr usermem.Addr = maxAddr64 / 6 * 5
+)
+
+var (
+ // CPUIDInstruction doesn't exist on ARM64.
+ CPUIDInstruction = []byte{}
+)
+
+// These constants are selected as heuristics to help make the Platform's
+// potentially limited address space conform as closely to Linux as possible.
+const (
+ preferredTopDownAllocMin usermem.Addr = 0x7e8000000000
+ preferredAllocationGap = 128 << 30 // 128 GB
+ preferredTopDownBaseMin = preferredTopDownAllocMin + preferredAllocationGap
+
+ // minMmapRand64 is the smallest we are willing to make the
+ // randomization to stay above preferredTopDownBaseMin.
+ minMmapRand64 = (1 << 18) * usermem.PageSize
+)
+
+// context64 represents an ARM64 context.
+type context64 struct {
+ State
+ sigFPState []aarch64FPState // fpstate to be restored on sigreturn.
+}
+
+// Arch implements Context.Arch.
+func (c *context64) Arch() Arch {
+ return ARM64
+}
+
+func (c *context64) copySigFPState() []aarch64FPState {
+ var sigfps []aarch64FPState
+ for _, s := range c.sigFPState {
+ sigfps = append(sigfps, s.fork())
+ }
+ return sigfps
+}
+
+// Fork returns an exact copy of this context.
+func (c *context64) Fork() Context {
+ return &context64{
+ State: c.State.Fork(),
+ sigFPState: c.copySigFPState(),
+ }
+}
+
+// General purpose registers usage on Arm64:
+// R0...R7: parameter/result registers.
+// R8: indirect result location register.
+// R9...R15: temporary rgisters.
+// R16: the first intra-procedure-call scratch register.
+// R17: the second intra-procedure-call scratch register.
+// R18: the platform register.
+// R19...R28: callee-saved registers.
+// R29: the frame pointer.
+// R30: the link register.
+
+// Return returns the current syscall return value.
+func (c *context64) Return() uintptr {
+ return uintptr(c.Regs.Regs[0])
+}
+
+// SetReturn sets the syscall return value.
+func (c *context64) SetReturn(value uintptr) {
+ c.Regs.Regs[0] = uint64(value)
+}
+
+// IP returns the current instruction pointer.
+func (c *context64) IP() uintptr {
+ return uintptr(c.Regs.Pc)
+}
+
+// SetIP sets the current instruction pointer.
+func (c *context64) SetIP(value uintptr) {
+ c.Regs.Pc = uint64(value)
+}
+
+// Stack returns the current stack pointer.
+func (c *context64) Stack() uintptr {
+ return uintptr(c.Regs.Sp)
+}
+
+// SetStack sets the current stack pointer.
+func (c *context64) SetStack(value uintptr) {
+ c.Regs.Sp = uint64(value)
+}
+
+// TLS returns the current TLS pointer.
+func (c *context64) TLS() uintptr {
+ return uintptr(c.TPValue)
+}
+
+// SetTLS sets the current TLS pointer. Returns false if value is invalid.
+func (c *context64) SetTLS(value uintptr) bool {
+ if value >= uintptr(maxAddr64) {
+ return false
+ }
+
+ c.TPValue = uint64(value)
+ return true
+}
+
+// SetOldRSeqInterruptedIP implements Context.SetOldRSeqInterruptedIP.
+func (c *context64) SetOldRSeqInterruptedIP(value uintptr) {
+ c.Regs.Regs[3] = uint64(value)
+}
+
+// Native returns the native type for the given val.
+func (c *context64) Native(val uintptr) interface{} {
+ v := uint64(val)
+ return &v
+}
+
+// Value returns the generic val for the given native type.
+func (c *context64) Value(val interface{}) uintptr {
+ return uintptr(*val.(*uint64))
+}
+
+// Width returns the byte width of this architecture.
+func (c *context64) Width() uint {
+ return 8
+}
+
+// FeatureSet returns the FeatureSet in use.
+func (c *context64) FeatureSet() *cpuid.FeatureSet {
+ return c.State.FeatureSet
+}
+
+// mmapRand returns a random adjustment for randomizing an mmap layout.
+func mmapRand(max uint64) usermem.Addr {
+ return usermem.Addr(rand.Int63n(int64(max))).RoundDown()
+}
+
+// NewMmapLayout implements Context.NewMmapLayout consistently with Linux.
+func (c *context64) NewMmapLayout(min, max usermem.Addr, r *limits.LimitSet) (MmapLayout, error) {
+ min, ok := min.RoundUp()
+ if !ok {
+ return MmapLayout{}, syscall.EINVAL
+ }
+ if max > maxAddr64 {
+ max = maxAddr64
+ }
+ max = max.RoundDown()
+
+ if min > max {
+ return MmapLayout{}, syscall.EINVAL
+ }
+
+ stackSize := r.Get(limits.Stack)
+
+ // MAX_GAP in Linux.
+ maxGap := (max / 6) * 5
+ gap := usermem.Addr(stackSize.Cur)
+ if gap < minGap64 {
+ gap = minGap64
+ }
+ if gap > maxGap {
+ gap = maxGap
+ }
+ defaultDir := MmapTopDown
+ if stackSize.Cur == limits.Infinity {
+ defaultDir = MmapBottomUp
+ }
+
+ topDownMin := max - gap - maxMmapRand64
+ maxRand := usermem.Addr(maxMmapRand64)
+ if topDownMin < preferredTopDownBaseMin {
+ // Try to keep TopDownBase above preferredTopDownBaseMin by
+ // shrinking maxRand.
+ maxAdjust := maxRand - minMmapRand64
+ needAdjust := preferredTopDownBaseMin - topDownMin
+ if needAdjust <= maxAdjust {
+ maxRand -= needAdjust
+ }
+ }
+
+ rnd := mmapRand(uint64(maxRand))
+ l := MmapLayout{
+ MinAddr: min,
+ MaxAddr: max,
+ // TASK_UNMAPPED_BASE in Linux.
+ BottomUpBase: (max/3 + rnd).RoundDown(),
+ TopDownBase: (max - gap - rnd).RoundDown(),
+ DefaultDirection: defaultDir,
+ // We may have reduced the maximum randomization to keep
+ // TopDownBase above preferredTopDownBaseMin while maintaining
+ // our stack gap. Stack allocations must use that max
+ // randomization to avoiding eating into the gap.
+ MaxStackRand: uint64(maxRand),
+ }
+
+ // Final sanity check on the layout.
+ if !l.Valid() {
+ panic(fmt.Sprintf("Invalid MmapLayout: %+v", l))
+ }
+
+ return l, nil
+}
+
+// PIELoadAddress implements Context.PIELoadAddress.
+func (c *context64) PIELoadAddress(l MmapLayout) usermem.Addr {
+ base := preferredPIELoadAddr
+ max, ok := base.AddLength(maxMmapRand64)
+ if !ok {
+ panic(fmt.Sprintf("preferredPIELoadAddr %#x too large", base))
+ }
+
+ if max > l.MaxAddr {
+ // preferredPIELoadAddr won't fit; fall back to the standard
+ // Linux behavior of 2/3 of TopDownBase. TSAN won't like this.
+ //
+ // Don't bother trying to shrink the randomization for now.
+ base = l.TopDownBase / 3 * 2
+ }
+
+ return base + mmapRand(maxMmapRand64)
+}
+
+// PtracePeekUser implements Context.PtracePeekUser.
+func (c *context64) PtracePeekUser(addr uintptr) (interface{}, error) {
+ // TODO(gvisor.dev/issue/1239): Full ptrace supporting for Arm64.
+ return c.Native(0), nil
+}
+
+// PtracePokeUser implements Context.PtracePokeUser.
+func (c *context64) PtracePokeUser(addr, data uintptr) error {
+ // TODO(gvisor.dev/issue/1239): Full ptrace supporting for Arm64.
+ return nil
+}
diff --git a/pkg/sentry/arch/arch_state_x86.go b/pkg/sentry/arch/arch_state_x86.go
index 9061fcc86..19ce99d25 100644
--- a/pkg/sentry/arch/arch_state_x86.go
+++ b/pkg/sentry/arch/arch_state_x86.go
@@ -12,14 +12,15 @@
// See the License for the specific language governing permissions and
// limitations under the License.
+// +build amd64 386
+
package arch
import (
"fmt"
- "syscall"
"gvisor.dev/gvisor/pkg/cpuid"
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/usermem"
)
// ErrFloatingPoint indicates a failed restore due to unusable floating point
@@ -41,8 +42,8 @@ func (e ErrFloatingPoint) Error() string {
// and SSE state, so this is the equivalent XSTATE_BV value.
const fxsaveBV uint64 = cpuid.XSAVEFeatureX87 | cpuid.XSAVEFeatureSSE
-// afterLoad is invoked by stateify.
-func (s *State) afterLoad() {
+// afterLoadFPState is invoked by afterLoad.
+func (s *State) afterLoadFPState() {
old := s.x86FPState
// Recreate the slice. This is done to ensure that it is aligned
@@ -88,44 +89,3 @@ func (s *State) afterLoad() {
// Copy to the new, aligned location.
copy(s.x86FPState, old)
}
-
-// +stateify savable
-type syscallPtraceRegs struct {
- R15 uint64
- R14 uint64
- R13 uint64
- R12 uint64
- Rbp uint64
- Rbx uint64
- R11 uint64
- R10 uint64
- R9 uint64
- R8 uint64
- Rax uint64
- Rcx uint64
- Rdx uint64
- Rsi uint64
- Rdi uint64
- Orig_rax uint64
- Rip uint64
- Cs uint64
- Eflags uint64
- Rsp uint64
- Ss uint64
- Fs_base uint64
- Gs_base uint64
- Ds uint64
- Es uint64
- Fs uint64
- Gs uint64
-}
-
-// saveRegs is invoked by stateify.
-func (s *State) saveRegs() syscallPtraceRegs {
- return syscallPtraceRegs(s.Regs)
-}
-
-// loadRegs is invoked by stateify.
-func (s *State) loadRegs(r syscallPtraceRegs) {
- s.Regs = syscall.PtraceRegs(r)
-}
diff --git a/pkg/sentry/arch/arch_x86.go b/pkg/sentry/arch/arch_x86.go
index 9294ac773..dc458b37f 100644
--- a/pkg/sentry/arch/arch_x86.go
+++ b/pkg/sentry/arch/arch_x86.go
@@ -12,24 +12,27 @@
// See the License for the specific language governing permissions and
// limitations under the License.
-// +build amd64 i386
+// +build amd64 386
package arch
import (
"fmt"
"io"
- "sync"
"syscall"
- "gvisor.dev/gvisor/pkg/binary"
+ "gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/cpuid"
"gvisor.dev/gvisor/pkg/log"
rpb "gvisor.dev/gvisor/pkg/sentry/arch/registers_go_proto"
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/sync"
"gvisor.dev/gvisor/pkg/syserror"
+ "gvisor.dev/gvisor/pkg/usermem"
)
+// Registers represents the CPU registers for this architecture.
+type Registers = linux.PtraceRegs
+
// System-related constants for x86.
const (
// SyscallWidth is the width of syscall, sysenter, and int 80 insturctions.
@@ -114,6 +117,10 @@ func newX86FPStateSlice() []byte {
size, align := cpuid.HostFeatureSet().ExtendedStateSize()
capacity := size
// Always use at least 4096 bytes.
+ //
+ // For the KVM platform, this state is a fixed 4096 bytes, so make sure
+ // that the underlying array is at _least_ that size otherwise we will
+ // corrupt random memory. This is not a pleasant thing to debug.
if capacity < 4096 {
capacity = 4096
}
@@ -151,21 +158,6 @@ func NewFloatingPointData() *FloatingPointData {
return (*FloatingPointData)(&(newX86FPState()[0]))
}
-// State contains the common architecture bits for X86 (the build tag of this
-// file ensures it's only built on x86).
-//
-// +stateify savable
-type State struct {
- // The system registers.
- Regs syscall.PtraceRegs `state:".(syscallPtraceRegs)"`
-
- // Our floating point state.
- x86FPState `state:"wait"`
-
- // FeatureSet is a pointer to the currently active feature set.
- FeatureSet *cpuid.FeatureSet
-}
-
// Proto returns a protobuf representation of the system registers in State.
func (s State) Proto() *rpb.Registers {
regs := &rpb.AMD64Registers{
@@ -278,10 +270,12 @@ func (s *State) RegisterMap() (map[string]uintptr, error) {
// PtraceGetRegs implements Context.PtraceGetRegs.
func (s *State) PtraceGetRegs(dst io.Writer) (int, error) {
- return dst.Write(binary.Marshal(nil, usermem.ByteOrder, s.ptraceGetRegs()))
+ regs := s.ptraceGetRegs()
+ n, err := regs.WriteTo(dst)
+ return int(n), err
}
-func (s *State) ptraceGetRegs() syscall.PtraceRegs {
+func (s *State) ptraceGetRegs() Registers {
regs := s.Regs
// These may not be initialized.
if regs.Cs == 0 || regs.Ss == 0 || regs.Eflags == 0 {
@@ -317,16 +311,16 @@ func (s *State) ptraceGetRegs() syscall.PtraceRegs {
return regs
}
-var ptraceRegsSize = int(binary.Size(syscall.PtraceRegs{}))
+var registersSize = (*Registers)(nil).SizeBytes()
// PtraceSetRegs implements Context.PtraceSetRegs.
func (s *State) PtraceSetRegs(src io.Reader) (int, error) {
- var regs syscall.PtraceRegs
- buf := make([]byte, ptraceRegsSize)
+ var regs Registers
+ buf := make([]byte, registersSize)
if _, err := io.ReadFull(src, buf); err != nil {
return 0, err
}
- binary.Unmarshal(buf, usermem.ByteOrder, &regs)
+ regs.UnmarshalUnsafe(buf)
// Truncate segment registers to 16 bits.
regs.Cs = uint64(uint16(regs.Cs))
regs.Ds = uint64(uint16(regs.Ds))
@@ -380,7 +374,7 @@ func (s *State) PtraceSetRegs(src io.Reader) (int, error) {
}
regs.Eflags = (s.Regs.Eflags &^ eflagsPtraceMutable) | (regs.Eflags & eflagsPtraceMutable)
s.Regs = regs
- return ptraceRegsSize, nil
+ return registersSize, nil
}
// isUserSegmentSelector returns true if the given segment selector specifies a
@@ -549,7 +543,7 @@ const (
func (s *State) PtraceGetRegSet(regset uintptr, dst io.Writer, maxlen int) (int, error) {
switch regset {
case _NT_PRSTATUS:
- if maxlen < ptraceRegsSize {
+ if maxlen < registersSize {
return 0, syserror.EFAULT
}
return s.PtraceGetRegs(dst)
@@ -569,7 +563,7 @@ func (s *State) PtraceGetRegSet(regset uintptr, dst io.Writer, maxlen int) (int,
func (s *State) PtraceSetRegSet(regset uintptr, src io.Reader, maxlen int) (int, error) {
switch regset {
case _NT_PRSTATUS:
- if maxlen < ptraceRegsSize {
+ if maxlen < registersSize {
return 0, syserror.EFAULT
}
return s.PtraceSetRegs(src)
diff --git a/pkg/sentry/arch/arch_x86_impl.go b/pkg/sentry/arch/arch_x86_impl.go
new file mode 100644
index 000000000..0c73fcbfb
--- /dev/null
+++ b/pkg/sentry/arch/arch_x86_impl.go
@@ -0,0 +1,41 @@
+// 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 amd64 386
+
+package arch
+
+import (
+ "gvisor.dev/gvisor/pkg/cpuid"
+)
+
+// State contains the common architecture bits for X86 (the build tag of this
+// file ensures it's only built on x86).
+//
+// +stateify savable
+type State struct {
+ // The system registers.
+ Regs Registers
+
+ // Our floating point state.
+ x86FPState `state:"wait"`
+
+ // FeatureSet is a pointer to the currently active feature set.
+ FeatureSet *cpuid.FeatureSet
+}
+
+// afterLoad is invoked by stateify.
+func (s *State) afterLoad() {
+ s.afterLoadFPState()
+}
diff --git a/pkg/sentry/arch/auxv.go b/pkg/sentry/arch/auxv.go
index 4546b2ef9..2b4c8f3fc 100644
--- a/pkg/sentry/arch/auxv.go
+++ b/pkg/sentry/arch/auxv.go
@@ -15,7 +15,7 @@
package arch
import (
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/usermem"
)
// An AuxEntry represents an entry in an ELF auxiliary vector.
diff --git a/pkg/sentry/arch/registers.proto b/pkg/sentry/arch/registers.proto
index 9dc83e241..60c027aab 100644
--- a/pkg/sentry/arch/registers.proto
+++ b/pkg/sentry/arch/registers.proto
@@ -48,8 +48,45 @@ message AMD64Registers {
uint64 gs_base = 27;
}
+message ARM64Registers {
+ uint64 r0 = 1;
+ uint64 r1 = 2;
+ uint64 r2 = 3;
+ uint64 r3 = 4;
+ uint64 r4 = 5;
+ uint64 r5 = 6;
+ uint64 r6 = 7;
+ uint64 r7 = 8;
+ uint64 r8 = 9;
+ uint64 r9 = 10;
+ uint64 r10 = 11;
+ uint64 r11 = 12;
+ uint64 r12 = 13;
+ uint64 r13 = 14;
+ uint64 r14 = 15;
+ uint64 r15 = 16;
+ uint64 r16 = 17;
+ uint64 r17 = 18;
+ uint64 r18 = 19;
+ uint64 r19 = 20;
+ uint64 r20 = 21;
+ uint64 r21 = 22;
+ uint64 r22 = 23;
+ uint64 r23 = 24;
+ uint64 r24 = 25;
+ uint64 r25 = 26;
+ uint64 r26 = 27;
+ uint64 r27 = 28;
+ uint64 r28 = 29;
+ uint64 r29 = 30;
+ uint64 r30 = 31;
+ uint64 sp = 32;
+ uint64 pc = 33;
+ uint64 pstate = 34;
+}
message Registers {
oneof arch {
AMD64Registers amd64 = 1;
+ ARM64Registers arm64 = 2;
}
}
diff --git a/pkg/sentry/arch/signal.go b/pkg/sentry/arch/signal.go
new file mode 100644
index 000000000..c9fb55d00
--- /dev/null
+++ b/pkg/sentry/arch/signal.go
@@ -0,0 +1,253 @@
+// 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 arch
+
+import (
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/usermem"
+)
+
+// SignalAct represents the action that should be taken when a signal is
+// delivered, and is equivalent to struct sigaction.
+//
+// +marshal
+// +stateify savable
+type SignalAct struct {
+ Handler uint64
+ Flags uint64
+ Restorer uint64 // Only used on amd64.
+ Mask linux.SignalSet
+}
+
+// SerializeFrom implements NativeSignalAct.SerializeFrom.
+func (s *SignalAct) SerializeFrom(other *SignalAct) {
+ *s = *other
+}
+
+// DeserializeTo implements NativeSignalAct.DeserializeTo.
+func (s *SignalAct) DeserializeTo(other *SignalAct) {
+ *other = *s
+}
+
+// SignalStack represents information about a user stack, and is equivalent to
+// stack_t.
+//
+// +marshal
+// +stateify savable
+type SignalStack struct {
+ Addr uint64
+ Flags uint32
+ _ uint32
+ Size uint64
+}
+
+// SerializeFrom implements NativeSignalStack.SerializeFrom.
+func (s *SignalStack) SerializeFrom(other *SignalStack) {
+ *s = *other
+}
+
+// DeserializeTo implements NativeSignalStack.DeserializeTo.
+func (s *SignalStack) DeserializeTo(other *SignalStack) {
+ *other = *s
+}
+
+// SignalInfo represents information about a signal being delivered, and is
+// equivalent to struct siginfo in linux kernel(linux/include/uapi/asm-generic/siginfo.h).
+//
+// +marshal
+// +stateify savable
+type SignalInfo struct {
+ Signo int32 // Signal number
+ Errno int32 // Errno value
+ Code int32 // Signal code
+ _ uint32
+
+ // struct siginfo::_sifields is a union. In SignalInfo, fields in the union
+ // are accessed through methods.
+ //
+ // For reference, here is the definition of _sifields: (_sigfault._trapno,
+ // which does not exist on x86, omitted for clarity)
+ //
+ // union {
+ // int _pad[SI_PAD_SIZE];
+ //
+ // /* kill() */
+ // struct {
+ // __kernel_pid_t _pid; /* sender's pid */
+ // __ARCH_SI_UID_T _uid; /* sender's uid */
+ // } _kill;
+ //
+ // /* POSIX.1b timers */
+ // struct {
+ // __kernel_timer_t _tid; /* timer id */
+ // int _overrun; /* overrun count */
+ // char _pad[sizeof( __ARCH_SI_UID_T) - sizeof(int)];
+ // sigval_t _sigval; /* same as below */
+ // int _sys_private; /* not to be passed to user */
+ // } _timer;
+ //
+ // /* POSIX.1b signals */
+ // struct {
+ // __kernel_pid_t _pid; /* sender's pid */
+ // __ARCH_SI_UID_T _uid; /* sender's uid */
+ // sigval_t _sigval;
+ // } _rt;
+ //
+ // /* SIGCHLD */
+ // struct {
+ // __kernel_pid_t _pid; /* which child */
+ // __ARCH_SI_UID_T _uid; /* sender's uid */
+ // int _status; /* exit code */
+ // __ARCH_SI_CLOCK_T _utime;
+ // __ARCH_SI_CLOCK_T _stime;
+ // } _sigchld;
+ //
+ // /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
+ // struct {
+ // void *_addr; /* faulting insn/memory ref. */
+ // short _addr_lsb; /* LSB of the reported address */
+ // } _sigfault;
+ //
+ // /* SIGPOLL */
+ // struct {
+ // __ARCH_SI_BAND_T _band; /* POLL_IN, POLL_OUT, POLL_MSG */
+ // int _fd;
+ // } _sigpoll;
+ //
+ // /* SIGSYS */
+ // struct {
+ // void *_call_addr; /* calling user insn */
+ // int _syscall; /* triggering system call number */
+ // unsigned int _arch; /* AUDIT_ARCH_* of syscall */
+ // } _sigsys;
+ // } _sifields;
+ //
+ // _sifields is padded so that the size of siginfo is SI_MAX_SIZE = 128
+ // bytes.
+ Fields [128 - 16]byte
+}
+
+// FixSignalCodeForUser fixes up si_code.
+//
+// The si_code we get from Linux may contain the kernel-specific code in the
+// top 16 bits if it's positive (e.g., from ptrace). Linux's
+// copy_siginfo_to_user does
+// err |= __put_user((short)from->si_code, &to->si_code);
+// to mask out those bits and we need to do the same.
+func (s *SignalInfo) FixSignalCodeForUser() {
+ if s.Code > 0 {
+ s.Code &= 0x0000ffff
+ }
+}
+
+// Pid returns the si_pid field.
+func (s *SignalInfo) Pid() int32 {
+ return int32(usermem.ByteOrder.Uint32(s.Fields[0:4]))
+}
+
+// SetPid mutates the si_pid field.
+func (s *SignalInfo) SetPid(val int32) {
+ usermem.ByteOrder.PutUint32(s.Fields[0:4], uint32(val))
+}
+
+// Uid returns the si_uid field.
+func (s *SignalInfo) Uid() int32 {
+ return int32(usermem.ByteOrder.Uint32(s.Fields[4:8]))
+}
+
+// SetUid mutates the si_uid field.
+func (s *SignalInfo) SetUid(val int32) {
+ usermem.ByteOrder.PutUint32(s.Fields[4:8], uint32(val))
+}
+
+// Sigval returns the sigval field, which is aliased to both si_int and si_ptr.
+func (s *SignalInfo) Sigval() uint64 {
+ return usermem.ByteOrder.Uint64(s.Fields[8:16])
+}
+
+// SetSigval mutates the sigval field.
+func (s *SignalInfo) SetSigval(val uint64) {
+ usermem.ByteOrder.PutUint64(s.Fields[8:16], val)
+}
+
+// TimerID returns the si_timerid field.
+func (s *SignalInfo) TimerID() linux.TimerID {
+ return linux.TimerID(usermem.ByteOrder.Uint32(s.Fields[0:4]))
+}
+
+// SetTimerID sets the si_timerid field.
+func (s *SignalInfo) SetTimerID(val linux.TimerID) {
+ usermem.ByteOrder.PutUint32(s.Fields[0:4], uint32(val))
+}
+
+// Overrun returns the si_overrun field.
+func (s *SignalInfo) Overrun() int32 {
+ return int32(usermem.ByteOrder.Uint32(s.Fields[4:8]))
+}
+
+// SetOverrun sets the si_overrun field.
+func (s *SignalInfo) SetOverrun(val int32) {
+ usermem.ByteOrder.PutUint32(s.Fields[4:8], uint32(val))
+}
+
+// Addr returns the si_addr field.
+func (s *SignalInfo) Addr() uint64 {
+ return usermem.ByteOrder.Uint64(s.Fields[0:8])
+}
+
+// SetAddr sets the si_addr field.
+func (s *SignalInfo) SetAddr(val uint64) {
+ usermem.ByteOrder.PutUint64(s.Fields[0:8], val)
+}
+
+// Status returns the si_status field.
+func (s *SignalInfo) Status() int32 {
+ return int32(usermem.ByteOrder.Uint32(s.Fields[8:12]))
+}
+
+// SetStatus mutates the si_status field.
+func (s *SignalInfo) SetStatus(val int32) {
+ usermem.ByteOrder.PutUint32(s.Fields[8:12], uint32(val))
+}
+
+// CallAddr returns the si_call_addr field.
+func (s *SignalInfo) CallAddr() uint64 {
+ return usermem.ByteOrder.Uint64(s.Fields[0:8])
+}
+
+// SetCallAddr mutates the si_call_addr field.
+func (s *SignalInfo) SetCallAddr(val uint64) {
+ usermem.ByteOrder.PutUint64(s.Fields[0:8], val)
+}
+
+// Syscall returns the si_syscall field.
+func (s *SignalInfo) Syscall() int32 {
+ return int32(usermem.ByteOrder.Uint32(s.Fields[8:12]))
+}
+
+// SetSyscall mutates the si_syscall field.
+func (s *SignalInfo) SetSyscall(val int32) {
+ usermem.ByteOrder.PutUint32(s.Fields[8:12], uint32(val))
+}
+
+// Arch returns the si_arch field.
+func (s *SignalInfo) Arch() uint32 {
+ return usermem.ByteOrder.Uint32(s.Fields[12:16])
+}
+
+// SetArch mutates the si_arch field.
+func (s *SignalInfo) SetArch(val uint32) {
+ usermem.ByteOrder.PutUint32(s.Fields[12:16], val)
+}
diff --git a/pkg/sentry/arch/signal_act.go b/pkg/sentry/arch/signal_act.go
index f9ca2e74e..32173aa20 100644
--- a/pkg/sentry/arch/signal_act.go
+++ b/pkg/sentry/arch/signal_act.go
@@ -14,6 +14,8 @@
package arch
+import "gvisor.dev/gvisor/tools/go_marshal/marshal"
+
// Special values for SignalAct.Handler.
const (
// SignalActDefault is SIG_DFL and specifies that the default behavior for
@@ -71,6 +73,8 @@ func (s SignalAct) HasRestorer() bool {
// NativeSignalAct is a type that is equivalent to struct sigaction in the
// guest architecture.
type NativeSignalAct interface {
+ marshal.Marshallable
+
// SerializeFrom copies the data in the host SignalAct s into this object.
SerializeFrom(s *SignalAct)
diff --git a/pkg/sentry/arch/signal_amd64.go b/pkg/sentry/arch/signal_amd64.go
index febd6f9b9..6fb756f0e 100644
--- a/pkg/sentry/arch/signal_amd64.go
+++ b/pkg/sentry/arch/signal_amd64.go
@@ -23,239 +23,9 @@ import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/log"
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/usermem"
)
-// SignalAct represents the action that should be taken when a signal is
-// delivered, and is equivalent to struct sigaction on 64-bit x86.
-//
-// +stateify savable
-type SignalAct struct {
- Handler uint64
- Flags uint64
- Restorer uint64
- Mask linux.SignalSet
-}
-
-// SerializeFrom implements NativeSignalAct.SerializeFrom.
-func (s *SignalAct) SerializeFrom(other *SignalAct) {
- *s = *other
-}
-
-// DeserializeTo implements NativeSignalAct.DeserializeTo.
-func (s *SignalAct) DeserializeTo(other *SignalAct) {
- *other = *s
-}
-
-// SignalStack represents information about a user stack, and is equivalent to
-// stack_t on 64-bit x86.
-//
-// +stateify savable
-type SignalStack struct {
- Addr uint64
- Flags uint32
- _ uint32
- Size uint64
-}
-
-// SerializeFrom implements NativeSignalStack.SerializeFrom.
-func (s *SignalStack) SerializeFrom(other *SignalStack) {
- *s = *other
-}
-
-// DeserializeTo implements NativeSignalStack.DeserializeTo.
-func (s *SignalStack) DeserializeTo(other *SignalStack) {
- *other = *s
-}
-
-// SignalInfo represents information about a signal being delivered, and is
-// equivalent to struct siginfo on 64-bit x86.
-//
-// +stateify savable
-type SignalInfo struct {
- Signo int32 // Signal number
- Errno int32 // Errno value
- Code int32 // Signal code
- _ uint32
-
- // struct siginfo::_sifields is a union. In SignalInfo, fields in the union
- // are accessed through methods.
- //
- // For reference, here is the definition of _sifields: (_sigfault._trapno,
- // which does not exist on x86, omitted for clarity)
- //
- // union {
- // int _pad[SI_PAD_SIZE];
- //
- // /* kill() */
- // struct {
- // __kernel_pid_t _pid; /* sender's pid */
- // __ARCH_SI_UID_T _uid; /* sender's uid */
- // } _kill;
- //
- // /* POSIX.1b timers */
- // struct {
- // __kernel_timer_t _tid; /* timer id */
- // int _overrun; /* overrun count */
- // char _pad[sizeof( __ARCH_SI_UID_T) - sizeof(int)];
- // sigval_t _sigval; /* same as below */
- // int _sys_private; /* not to be passed to user */
- // } _timer;
- //
- // /* POSIX.1b signals */
- // struct {
- // __kernel_pid_t _pid; /* sender's pid */
- // __ARCH_SI_UID_T _uid; /* sender's uid */
- // sigval_t _sigval;
- // } _rt;
- //
- // /* SIGCHLD */
- // struct {
- // __kernel_pid_t _pid; /* which child */
- // __ARCH_SI_UID_T _uid; /* sender's uid */
- // int _status; /* exit code */
- // __ARCH_SI_CLOCK_T _utime;
- // __ARCH_SI_CLOCK_T _stime;
- // } _sigchld;
- //
- // /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
- // struct {
- // void *_addr; /* faulting insn/memory ref. */
- // short _addr_lsb; /* LSB of the reported address */
- // } _sigfault;
- //
- // /* SIGPOLL */
- // struct {
- // __ARCH_SI_BAND_T _band; /* POLL_IN, POLL_OUT, POLL_MSG */
- // int _fd;
- // } _sigpoll;
- //
- // /* SIGSYS */
- // struct {
- // void *_call_addr; /* calling user insn */
- // int _syscall; /* triggering system call number */
- // unsigned int _arch; /* AUDIT_ARCH_* of syscall */
- // } _sigsys;
- // } _sifields;
- //
- // _sifields is padded so that the size of siginfo is SI_MAX_SIZE = 128
- // bytes.
- Fields [128 - 16]byte
-}
-
-// FixSignalCodeForUser fixes up si_code.
-//
-// The si_code we get from Linux may contain the kernel-specific code in the
-// top 16 bits if it's positive (e.g., from ptrace). Linux's
-// copy_siginfo_to_user does
-// err |= __put_user((short)from->si_code, &to->si_code);
-// to mask out those bits and we need to do the same.
-func (s *SignalInfo) FixSignalCodeForUser() {
- if s.Code > 0 {
- s.Code &= 0x0000ffff
- }
-}
-
-// Pid returns the si_pid field.
-func (s *SignalInfo) Pid() int32 {
- return int32(usermem.ByteOrder.Uint32(s.Fields[0:4]))
-}
-
-// SetPid mutates the si_pid field.
-func (s *SignalInfo) SetPid(val int32) {
- usermem.ByteOrder.PutUint32(s.Fields[0:4], uint32(val))
-}
-
-// Uid returns the si_uid field.
-func (s *SignalInfo) Uid() int32 {
- return int32(usermem.ByteOrder.Uint32(s.Fields[4:8]))
-}
-
-// SetUid mutates the si_uid field.
-func (s *SignalInfo) SetUid(val int32) {
- usermem.ByteOrder.PutUint32(s.Fields[4:8], uint32(val))
-}
-
-// Sigval returns the sigval field, which is aliased to both si_int and si_ptr.
-func (s *SignalInfo) Sigval() uint64 {
- return usermem.ByteOrder.Uint64(s.Fields[8:16])
-}
-
-// SetSigval mutates the sigval field.
-func (s *SignalInfo) SetSigval(val uint64) {
- usermem.ByteOrder.PutUint64(s.Fields[8:16], val)
-}
-
-// TimerID returns the si_timerid field.
-func (s *SignalInfo) TimerID() linux.TimerID {
- return linux.TimerID(usermem.ByteOrder.Uint32(s.Fields[0:4]))
-}
-
-// SetTimerID sets the si_timerid field.
-func (s *SignalInfo) SetTimerID(val linux.TimerID) {
- usermem.ByteOrder.PutUint32(s.Fields[0:4], uint32(val))
-}
-
-// Overrun returns the si_overrun field.
-func (s *SignalInfo) Overrun() int32 {
- return int32(usermem.ByteOrder.Uint32(s.Fields[4:8]))
-}
-
-// SetOverrun sets the si_overrun field.
-func (s *SignalInfo) SetOverrun(val int32) {
- usermem.ByteOrder.PutUint32(s.Fields[4:8], uint32(val))
-}
-
-// Addr returns the si_addr field.
-func (s *SignalInfo) Addr() uint64 {
- return usermem.ByteOrder.Uint64(s.Fields[0:8])
-}
-
-// SetAddr sets the si_addr field.
-func (s *SignalInfo) SetAddr(val uint64) {
- usermem.ByteOrder.PutUint64(s.Fields[0:8], val)
-}
-
-// Status returns the si_status field.
-func (s *SignalInfo) Status() int32 {
- return int32(usermem.ByteOrder.Uint32(s.Fields[8:12]))
-}
-
-// SetStatus mutates the si_status field.
-func (s *SignalInfo) SetStatus(val int32) {
- usermem.ByteOrder.PutUint32(s.Fields[8:12], uint32(val))
-}
-
-// CallAddr returns the si_call_addr field.
-func (s *SignalInfo) CallAddr() uint64 {
- return usermem.ByteOrder.Uint64(s.Fields[0:8])
-}
-
-// SetCallAddr mutates the si_call_addr field.
-func (s *SignalInfo) SetCallAddr(val uint64) {
- usermem.ByteOrder.PutUint64(s.Fields[0:8], val)
-}
-
-// Syscall returns the si_syscall field.
-func (s *SignalInfo) Syscall() int32 {
- return int32(usermem.ByteOrder.Uint32(s.Fields[8:12]))
-}
-
-// SetSyscall mutates the si_syscall field.
-func (s *SignalInfo) SetSyscall(val int32) {
- usermem.ByteOrder.PutUint32(s.Fields[8:12], uint32(val))
-}
-
-// Arch returns the si_arch field.
-func (s *SignalInfo) Arch() uint32 {
- return usermem.ByteOrder.Uint32(s.Fields[12:16])
-}
-
-// SetArch mutates the si_arch field.
-func (s *SignalInfo) SetArch(val uint32) {
- usermem.ByteOrder.PutUint32(s.Fields[12:16], val)
-}
-
// SignalContext64 is equivalent to struct sigcontext, the type passed as the
// second argument to signal handlers set by signal(2).
type SignalContext64 struct {
@@ -285,7 +55,7 @@ type SignalContext64 struct {
Trapno uint64
Oldmask linux.SignalSet
Cr2 uint64
- // Pointer to a struct _fpstate.
+ // Pointer to a struct _fpstate. See b/33003106#comment8.
Fpstate uint64
Reserved [8]uint64
}
diff --git a/pkg/sentry/arch/signal_arm64.go b/pkg/sentry/arch/signal_arm64.go
new file mode 100644
index 000000000..1cb1adf8c
--- /dev/null
+++ b/pkg/sentry/arch/signal_arm64.go
@@ -0,0 +1,159 @@
+// 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 arch
+
+import (
+ "encoding/binary"
+ "syscall"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/usermem"
+)
+
+// SignalContext64 is equivalent to struct sigcontext, the type passed as the
+// second argument to signal handlers set by signal(2).
+type SignalContext64 struct {
+ FaultAddr uint64
+ Regs [31]uint64
+ Sp uint64
+ Pc uint64
+ Pstate uint64
+ _pad [8]byte // __attribute__((__aligned__(16)))
+ Fpsimd64 FpsimdContext // size = 528
+ Reserved [3568]uint8
+}
+
+type aarch64Ctx struct {
+ Magic uint32
+ Size uint32
+}
+
+// FpsimdContext is equivalent to struct fpsimd_context on arm64
+// (arch/arm64/include/uapi/asm/sigcontext.h).
+type FpsimdContext struct {
+ Head aarch64Ctx
+ Fpsr uint32
+ Fpcr uint32
+ Vregs [64]uint64 // actually [32]uint128
+}
+
+// UContext64 is equivalent to ucontext on arm64(arch/arm64/include/uapi/asm/ucontext.h).
+type UContext64 struct {
+ Flags uint64
+ Link uint64
+ Stack SignalStack
+ Sigset linux.SignalSet
+ // glibc uses a 1024-bit sigset_t
+ _pad [(1024 - 64) / 8]byte
+ // sigcontext must be aligned to 16-byte
+ _pad2 [8]byte
+ // last for future expansion
+ MContext SignalContext64
+}
+
+// NewSignalAct implements Context.NewSignalAct.
+func (c *context64) NewSignalAct() NativeSignalAct {
+ return &SignalAct{}
+}
+
+// NewSignalStack implements Context.NewSignalStack.
+func (c *context64) NewSignalStack() NativeSignalStack {
+ return &SignalStack{}
+}
+
+// SignalSetup implements Context.SignalSetup.
+func (c *context64) SignalSetup(st *Stack, act *SignalAct, info *SignalInfo, alt *SignalStack, sigset linux.SignalSet) error {
+ sp := st.Bottom
+
+ if !(alt.IsEnabled() && sp == alt.Top()) {
+ sp -= 128
+ }
+
+ // Construct the UContext64 now since we need its size.
+ uc := &UContext64{
+ Flags: 0,
+ Stack: *alt,
+ MContext: SignalContext64{
+ Regs: c.Regs.Regs,
+ Sp: c.Regs.Sp,
+ Pc: c.Regs.Pc,
+ Pstate: c.Regs.Pstate,
+ },
+ Sigset: sigset,
+ }
+
+ ucSize := binary.Size(uc)
+ if ucSize < 0 {
+ panic("can't get size of UContext64")
+ }
+
+ // frameSize = ucSize + sizeof(siginfo).
+ // sizeof(siginfo) == 128.
+ // R30 stores the restorer address.
+ frameSize := ucSize + 128
+ frameBottom := (sp - usermem.Addr(frameSize)) & ^usermem.Addr(15)
+ sp = frameBottom + usermem.Addr(frameSize)
+ st.Bottom = sp
+
+ // Prior to proceeding, figure out if the frame will exhaust the range
+ // for the signal stack. This is not allowed, and should immediately
+ // force signal delivery (reverting to the default handler).
+ if act.IsOnStack() && alt.IsEnabled() && !alt.Contains(frameBottom) {
+ return syscall.EFAULT
+ }
+
+ // Adjust the code.
+ info.FixSignalCodeForUser()
+
+ // Set up the stack frame.
+ infoAddr, err := st.Push(info)
+ if err != nil {
+ return err
+ }
+ ucAddr, err := st.Push(uc)
+ if err != nil {
+ return err
+ }
+
+ // Set up registers.
+ c.Regs.Sp = uint64(st.Bottom)
+ c.Regs.Pc = act.Handler
+ c.Regs.Regs[0] = uint64(info.Signo)
+ c.Regs.Regs[1] = uint64(infoAddr)
+ c.Regs.Regs[2] = uint64(ucAddr)
+ c.Regs.Regs[30] = uint64(act.Restorer)
+ return nil
+}
+
+// SignalRestore implements Context.SignalRestore.
+func (c *context64) SignalRestore(st *Stack, rt bool) (linux.SignalSet, SignalStack, error) {
+ // Copy out the stack frame.
+ var uc UContext64
+ if _, err := st.Pop(&uc); err != nil {
+ return 0, SignalStack{}, err
+ }
+ var info SignalInfo
+ if _, err := st.Pop(&info); err != nil {
+ return 0, SignalStack{}, err
+ }
+
+ // Restore registers.
+ c.Regs.Regs = uc.MContext.Regs
+ c.Regs.Pc = uc.MContext.Pc
+ c.Regs.Sp = uc.MContext.Sp
+ c.Regs.Pstate = uc.MContext.Pstate
+
+ return uc.Sigset, uc.Stack, nil
+}
diff --git a/pkg/sentry/arch/signal_stack.go b/pkg/sentry/arch/signal_stack.go
index 5a3228113..0fa738a1d 100644
--- a/pkg/sentry/arch/signal_stack.go
+++ b/pkg/sentry/arch/signal_stack.go
@@ -12,12 +12,13 @@
// See the License for the specific language governing permissions and
// limitations under the License.
-// +build i386 amd64
+// +build 386 amd64 arm64
package arch
import (
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/usermem"
+ "gvisor.dev/gvisor/tools/go_marshal/marshal"
)
const (
@@ -55,6 +56,8 @@ func (s *SignalStack) Contains(sp usermem.Addr) bool {
// NativeSignalStack is a type that is equivalent to stack_t in the guest
// architecture.
type NativeSignalStack interface {
+ marshal.Marshallable
+
// SerializeFrom copies the data in the host SignalStack s into this
// object.
SerializeFrom(s *SignalStack)
diff --git a/pkg/sentry/arch/stack.go b/pkg/sentry/arch/stack.go
index 7472c3c61..1108fa0bd 100644
--- a/pkg/sentry/arch/stack.go
+++ b/pkg/sentry/arch/stack.go
@@ -18,8 +18,8 @@ import (
"encoding/binary"
"fmt"
- "gvisor.dev/gvisor/pkg/sentry/context"
- "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/context"
+ "gvisor.dev/gvisor/pkg/usermem"
)
// Stack is a simple wrapper around a usermem.IO and an address.
@@ -97,7 +97,6 @@ func (s *Stack) Push(vals ...interface{}) (usermem.Addr, error) {
if c < 0 {
return 0, fmt.Errorf("bad binary.Size for %T", v)
}
- // TODO(b/38173783): Use a real context.Context.
n, err := usermem.CopyObjectOut(context.Background(), s.IO, s.Bottom-usermem.Addr(c), norm, usermem.IOOpts{})
if err != nil || c != n {
return 0, err
@@ -121,11 +120,9 @@ func (s *Stack) Pop(vals ...interface{}) (usermem.Addr, error) {
var err error
if isVaddr {
value := s.Arch.Native(uintptr(0))
- // TODO(b/38173783): Use a real context.Context.
n, err = usermem.CopyObjectIn(context.Background(), s.IO, s.Bottom, value, usermem.IOOpts{})
*vaddr = usermem.Addr(s.Arch.Value(value))
} else {
- // TODO(b/38173783): Use a real context.Context.
n, err = usermem.CopyObjectIn(context.Background(), s.IO, s.Bottom, v, usermem.IOOpts{})
}
if err != nil {
diff --git a/pkg/sentry/arch/syscalls_amd64.go b/pkg/sentry/arch/syscalls_amd64.go
index 8b4f23007..3859f41ee 100644
--- a/pkg/sentry/arch/syscalls_amd64.go
+++ b/pkg/sentry/arch/syscalls_amd64.go
@@ -18,6 +18,13 @@ package arch
const restartSyscallNr = uintptr(219)
+// SyscallSaveOrig save the value of the register which is clobbered in
+// syscall handler(doSyscall()).
+//
+// Noop on x86.
+func (c *context64) SyscallSaveOrig() {
+}
+
// SyscallNo returns the syscall number according to the 64-bit convention.
func (c *context64) SyscallNo() uintptr {
return uintptr(c.Regs.Orig_rax)
diff --git a/pkg/sentry/arch/syscalls_arm64.go b/pkg/sentry/arch/syscalls_arm64.go
new file mode 100644
index 000000000..92d062513
--- /dev/null
+++ b/pkg/sentry/arch/syscalls_arm64.go
@@ -0,0 +1,81 @@
+// 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 arch
+
+const restartSyscallNr = uintptr(128)
+
+// SyscallSaveOrig save the value of the register R0 which is clobbered in
+// syscall handler(doSyscall()).
+//
+// In linux, at the entry of the syscall handler(el0_svc_common()), value of R0
+// is saved to the pt_regs.orig_x0 in kernel code. But currently, the orig_x0
+// was not accessible to the user space application, so we have to do the same
+// operation in the sentry code to save the R0 value into the App context.
+func (c *context64) SyscallSaveOrig() {
+ c.OrigR0 = c.Regs.Regs[0]
+}
+
+// SyscallNo returns the syscall number according to the 64-bit convention.
+func (c *context64) SyscallNo() uintptr {
+ return uintptr(c.Regs.Regs[8])
+}
+
+// SyscallArgs provides syscall arguments according to the 64-bit convention.
+//
+// Due to the way addresses are mapped for the sentry this binary *must* be
+// built in 64-bit mode. So we can just assume the syscall numbers that come
+// back match the expected host system call numbers.
+// General purpose registers usage on Arm64:
+// R0...R7: parameter/result registers.
+// R8: indirect result location register.
+// R9...R15: temporary registers.
+// R16: the first intra-procedure-call scratch register.
+// R17: the second intra-procedure-call scratch register.
+// R18: the platform register.
+// R19...R28: callee-saved registers.
+// R29: the frame pointer.
+// R30: the link register.
+func (c *context64) SyscallArgs() SyscallArguments {
+ return SyscallArguments{
+ SyscallArgument{Value: uintptr(c.OrigR0)},
+ SyscallArgument{Value: uintptr(c.Regs.Regs[1])},
+ SyscallArgument{Value: uintptr(c.Regs.Regs[2])},
+ SyscallArgument{Value: uintptr(c.Regs.Regs[3])},
+ SyscallArgument{Value: uintptr(c.Regs.Regs[4])},
+ SyscallArgument{Value: uintptr(c.Regs.Regs[5])},
+ }
+}
+
+// RestartSyscall implements Context.RestartSyscall.
+// Prepare for system call restart, OrigR0 will be restored to R0.
+// Please see the linux code as reference:
+// arch/arm64/kernel/signal.c:do_signal()
+func (c *context64) RestartSyscall() {
+ c.Regs.Pc -= SyscallWidth
+ // R0 will be backed up into OrigR0 when entering doSyscall().
+ // Please see the linux code as reference:
+ // arch/arm64/kernel/syscall.c:el0_svc_common().
+ // Here we restore it back.
+ c.Regs.Regs[0] = uint64(c.OrigR0)
+}
+
+// RestartSyscallWithRestartBlock implements Context.RestartSyscallWithRestartBlock.
+func (c *context64) RestartSyscallWithRestartBlock() {
+ c.Regs.Pc -= SyscallWidth
+ c.Regs.Regs[0] = uint64(c.OrigR0)
+ c.Regs.Regs[8] = uint64(restartSyscallNr)
+}