please,

read "Private variables in a C++ class can't be accessed directly" in the
correct perspective.

Hackers operate from outside the process, not from inside the process.


Il giorno lun 17 feb 2025 alle ore 11:10 Amit via Std-Discussion <
std-discussion_at_[hidden]> ha scritto:

> I don't know. I am not a hacker. I am just saying that may be hackers know
> or may be not.
>
> But I can definitely mess up any object. So, data is not quite safe in C++
> as it has been advertised.
>
> "Private variables in a C++ class can't be accessed directly" is a very
> popular statement.
>
> Regards,
> Amit
>
>
> On Mon, Feb 17, 2025, 3:29 PM Tiago Freire <tmiguelf_at_[hidden]> wrote:
>
>> How?
>>
>>
>>
>>
>>
>> *From:* Std-Discussion <std-discussion-bounces_at_[hidden]> *On
>> Behalf Of *Amit via Std-Discussion
>> *Sent:* Monday, February 17, 2025 10:54 AM
>> *To:* Jan Schultke <janschultke_at_[hidden]>
>> *Cc:* Amit <amitchoudhary0523_at_[hidden]>; std-discussion_at_[hidden]
>> *Subject:* Re: [std-discussion] C++ language has a big security hole.
>>
>>
>>
>> In all C++ object layouts, I have seen that members follow the previous
>> one as in a C structure.
>>
>>
>>
>> My main point is that hackers/bad people can take advantage of this.
>>
>>
>>
>> Regards,
>>
>> Amit
>>
>>
>>
>>
>>
>> On Mon, Feb 17, 2025, 3:17 PM Jan Schultke <janschultke_at_[hidden]>
>> wrote:
>>
>> Your code has undefined behavior because you cannot obtain your j_ptr
>> by doing i_ptr + 1. A past the end pointer is not a pointer to the
>> next member.
>>
>> However, the example is correct without j_ptr. It is possible to
>> obtain a pointer to the first member of a standard-layout class such
>> as MyClass, even if that member is private.
>>
>> I wouldn't really call it a security hole. The only way you will do
>> this in idiomatic C++ code is with reinterpret_cast, and
>> reinterpret_cast is a giant red flag which says "I'm an expert, I know
>> what I'm doing, and what I'm doing is potentially dangerous". This
>> never happens by accident.
>>
>> --
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