24ec1754b2
the maximum size of the Xsave area was previously hardcoded but the CPUID instruction can be used to determine its maximum size.
94 lines
3.4 KiB
Go
94 lines
3.4 KiB
Go
package native
|
||
|
||
import "C"
|
||
|
||
import (
|
||
"fmt"
|
||
"syscall"
|
||
"unsafe"
|
||
|
||
sys "golang.org/x/sys/unix"
|
||
|
||
"github.com/go-delve/delve/pkg/proc/amd64util"
|
||
)
|
||
|
||
// ptraceGetRegset returns floating point registers of the specified thread
|
||
// using PTRACE.
|
||
// See i386_linux_fetch_inferior_registers in gdb/i386-linux-nat.c.html
|
||
// and i386_supply_xsave in gdb/i386-tdep.c.html
|
||
// and Section 13.1 (and following) of Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 1: Basic Architecture
|
||
func ptraceGetRegset(tid int) (regset amd64util.AMD64Xstate, err error) {
|
||
_, _, err = syscall.Syscall6(syscall.SYS_PTRACE, sys.PTRACE_GETFPREGS, uintptr(tid), uintptr(0), uintptr(unsafe.Pointer(®set.AMD64PtraceFpRegs)), 0, 0)
|
||
if err == syscall.Errno(0) || err == syscall.ENODEV {
|
||
// ignore ENODEV, it just means this CPU doesn't have X87 registers (??)
|
||
err = nil
|
||
}
|
||
|
||
xstateargs := make([]byte, amd64util.AMD64XstateMaxSize())
|
||
iov := sys.Iovec{Base: &xstateargs[0], Len: uint32(len(xstateargs))}
|
||
_, _, err = syscall.Syscall6(syscall.SYS_PTRACE, sys.PTRACE_GETREGSET, uintptr(tid), _NT_X86_XSTATE, uintptr(unsafe.Pointer(&iov)), 0, 0)
|
||
if err != syscall.Errno(0) {
|
||
if err == syscall.ENODEV || err == syscall.EIO {
|
||
// ignore ENODEV, it just means this CPU or kernel doesn't support XSTATE, see https://github.com/go-delve/delve/issues/1022
|
||
// also ignore EIO, it means that we are running on an old kernel (pre 2.6.34) and PTRACE_GETREGSET is not implemented
|
||
err = nil
|
||
}
|
||
return
|
||
} else {
|
||
err = nil
|
||
}
|
||
|
||
regset.Xsave = xstateargs[:iov.Len]
|
||
err = amd64util.AMD64XstateRead(regset.Xsave, false, ®set)
|
||
return
|
||
}
|
||
|
||
// ptraceGetTls return the addr of tls by PTRACE_GET_THREAD_AREA for specify thread.
|
||
// See http://man7.org/linux/man-pages/man2/ptrace.2.html for detail about PTRACE_GET_THREAD_AREA.
|
||
// struct user_desc at https://golang.org/src/runtime/sys_linux_386.s
|
||
// type UserDesc struct {
|
||
// EntryNumber uint32
|
||
// BaseAddr uint32
|
||
// Limit uint32
|
||
// Flag uint32
|
||
// }
|
||
func ptraceGetTls(gs int32, tid int) (uint32, error) {
|
||
ud := [4]uint32{}
|
||
|
||
// Gs usually is 0x33
|
||
_, _, err := syscall.Syscall6(syscall.SYS_PTRACE, sys.PTRACE_GET_THREAD_AREA, uintptr(tid), uintptr(gs>>3), uintptr(unsafe.Pointer(&ud)), 0, 0)
|
||
if err == syscall.ENODEV || err == syscall.EIO {
|
||
return 0, fmt.Errorf("%s", err)
|
||
}
|
||
|
||
return uint32(ud[1]), nil
|
||
}
|
||
|
||
// processVmRead calls process_vm_readv
|
||
func processVmRead(tid int, addr uintptr, data []byte) (int, error) {
|
||
len_iov := uint32(len(data))
|
||
local_iov := sys.Iovec{Base: &data[0], Len: len_iov}
|
||
remote_iov := sys.Iovec{Base: (*byte)(unsafe.Pointer(addr)), Len: len_iov}
|
||
p_local := uintptr(unsafe.Pointer(&local_iov))
|
||
p_remote := uintptr(unsafe.Pointer(&remote_iov))
|
||
n, _, err := syscall.Syscall6(sys.SYS_PROCESS_VM_READV, uintptr(tid), p_local, 1, p_remote, 1, 0)
|
||
if err != syscall.Errno(0) {
|
||
return 0, err
|
||
}
|
||
return int(n), nil
|
||
}
|
||
|
||
// processVmWrite calls process_vm_writev
|
||
func processVmWrite(tid int, addr uintptr, data []byte) (int, error) {
|
||
len_iov := uint32(len(data))
|
||
local_iov := sys.Iovec{Base: &data[0], Len: len_iov}
|
||
remote_iov := sys.Iovec{Base: (*byte)(unsafe.Pointer(addr)), Len: len_iov}
|
||
p_local := uintptr(unsafe.Pointer(&local_iov))
|
||
p_remote := uintptr(unsafe.Pointer(&remote_iov))
|
||
n, _, err := syscall.Syscall6(sys.SYS_PROCESS_VM_WRITEV, uintptr(tid), p_local, 1, p_remote, 1, 0)
|
||
if err != syscall.Errno(0) {
|
||
return 0, err
|
||
}
|
||
return int(n), nil
|
||
}
|