gsrlabs/sys
1
0
Fork 0
mirror of https://github.com/golang/sys.git synced 2026-02-08 03:36:03 +03:00
Code Issues Packages Projects Releases Wiki Activity

windows/registry: do not generate unaligned loads

Browse Source 
Byte slices aren't necessarily aligned, which means casting them to
integer types and dereferencing may result in an unaligned load. This
is mostly fine on Intel but isn't necessarily fine on other platforms.
Any good compiler will generate optimal code for the platform using the
pattern of this commit.

Change-Id: I6dd8debad1cb850b8562ee96ae0f366d1f822a6f
Reviewed-on: https://go-review.googlesource.com/c/sys/+/176857
Run-TryBot: Jason Donenfeld <Jason@zx2c4.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This commit is contained in:
Jason A. Donenfeld
2019-05-13 13:22:04 +02:00
committed by Ian Lance Taylor
parent c432e742b0
commit c46e0d965b
1 changed files with 6 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
windows/registry/value.go
View File

@@ -68,7 +68,7 @@ func (k Key) GetValue(name string, buf []byte) (n int, valtype uint32, err error
return int(l), valtype, nil
}
func (k Key) getValue(name string, buf []byte) (date []byte, valtype uint32, err error) {
func (k Key) getValue(name string, buf []byte) (data []byte, valtype uint32, err error) {
p, err := syscall.UTF16PtrFromString(name)
if err != nil {
return nil, 0, err
@@ -241,12 +241,15 @@ func (k Key) GetIntegerValue(name string) (val uint64, valtype uint32, err error
if len(data) != 4 {
return 0, typ, errors.New("DWORD value is not 4 bytes long")
}
return uint64(*(*uint32)(unsafe.Pointer(&data[0]))), DWORD, nil
var val32 uint32
copy((*[4]byte)(unsafe.Pointer(&val32))[:], data)
return uint64(val32), DWORD, nil
case QWORD:
if len(data) != 8 {
return 0, typ, errors.New("QWORD value is not 8 bytes long")
}
return uint64(*(*uint64)(unsafe.Pointer(&data[0]))), QWORD, nil
copy((*[8]byte)(unsafe.Pointer(&val))[:], data)
return val, QWORD, nil
default:
return 0, typ, ErrUnexpectedType
}