01 |
VOID RtlInitUnicodeString (OUT PUNICODE_STRING DestinationString,IN PCWSTR SourceString OPTIONAL) |
02 |
{ |
03 |
SIZE_T Length; |
04 |
DestinationString->MaximumLength = 0; |
05 |
DestinationString->Length = 0; |
06 |
DestinationString->Buffer = (PWSTR)SourceString; |
07 |
if (ARGUMENT_PRESENT(SourceString)) |
08 |
{ |
09 |
Length = wcslen(SourceString) * sizeof(WCHAR); |
10 |
ASSERT(Length < MAX_USTRING); |
11 |
if(Length >= MAX_USTRING) |
12 |
{ |
13 |
Length = MAX_USTRING - sizeof(UNICODE_NULL); |
14 |
} |
15 |
DestinationString->Length = (USHORT)Length; |
16 |
DestinationString->MaximumLength = (USHORT)(Length + sizeof(UNICODE_NULL)); |
17 |
} |
18 |
return; |
19 |
} |
20 |
21 |
NTSTATUS RtlInitUnicodeStringEx ( OUT PUNICODE_STRING DestinationString,IN PCWSTR SourceString OPTIONAL) |
22 |
{ |
23 |
SIZE_T Length; |
24 |
DestinationString->Length = 0; |
25 |
DestinationString->MaximumLength = 0; |
26 |
DestinationString->Buffer = (PWSTR)SourceString; |
27 |
if (ARGUMENT_PRESENT(SourceString)) |
28 |
{ |
29 |
Length = wcslen(SourceString); |
30 |
// We are actually limited to 32765 characters since we want to store a meaningful MaximumLength also. |
31 |
if (Length > (UNICODE_STRING_MAX_CHARS - 1)) |
32 |
{ |
33 |
return STATUS_NAME_TOO_LONG; |
34 |
} |
35 |
Length *= sizeof(WCHAR); |
36 |
DestinationString->Length = (USHORT)Length; |
37 |
DestinationString->MaximumLength = (USHORT)(Length + sizeof(WCHAR)); |
38 |
} |
39 |
return STATUS_SUCCESS; |
40 |
} |
从以上代码可见，这2个函数会将传入的字符串指针直接赋值给结构体，这样的话，如果传入的是栈字符串，那么UNICODE_STIRNG只能在当前域内使用，不能存储到其他生命周期更长的地方，否则栈恢复以后读取到不正确的数据，
然而传入一个全局字符串是可以的，例如：
UNICODE_STRING str1;
void func()
{
WCHAR buf[]=L"lich";
RtlInitUnicodeString(&str1,buf);
}
这是错误写法
https://www.0xaa55.com/forum.php?mod=viewthread&tid=1371&extra=page%3D6
时间： 2024-12-25 18:34:39