github.com/MerlinKodo/gvisor@v0.0.0-20231110090155-957f62ecf90e/pkg/sentry/platform/ptrace/ptrace_arm64_unsafe.go (about)

     1  // Copyright 2020 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  //go:build arm64
    16  // +build arm64
    17  
    18  package ptrace
    19  
    20  import (
    21  	"unsafe"
    22  
    23  	"github.com/MerlinKodo/gvisor/pkg/abi/linux"
    24  	"golang.org/x/sys/unix"
    25  )
    26  
    27  // getTLS gets the thread local storage register.
    28  func (t *thread) getTLS(tls *uint64) error {
    29  	iovec := unix.Iovec{
    30  		Base: (*byte)(unsafe.Pointer(tls)),
    31  		Len:  uint64(unsafe.Sizeof(*tls)),
    32  	}
    33  	_, _, errno := unix.RawSyscall6(
    34  		unix.SYS_PTRACE,
    35  		unix.PTRACE_GETREGSET,
    36  		uintptr(t.tid),
    37  		linux.NT_ARM_TLS,
    38  		uintptr(unsafe.Pointer(&iovec)),
    39  		0, 0)
    40  	if errno != 0 {
    41  		return errno
    42  	}
    43  	return nil
    44  }
    45  
    46  // setTLS sets the thread local storage register.
    47  func (t *thread) setTLS(tls *uint64) error {
    48  	iovec := unix.Iovec{
    49  		Base: (*byte)(unsafe.Pointer(tls)),
    50  		Len:  uint64(unsafe.Sizeof(*tls)),
    51  	}
    52  	_, _, errno := unix.RawSyscall6(
    53  		unix.SYS_PTRACE,
    54  		unix.PTRACE_SETREGSET,
    55  		uintptr(t.tid),
    56  		linux.NT_ARM_TLS,
    57  		uintptr(unsafe.Pointer(&iovec)),
    58  		0, 0)
    59  	if errno != 0 {
    60  		return errno
    61  	}
    62  	return nil
    63  }