[Gammaray-interest] New plugin idea: Event inspector

[Christian Gagneraud]

On 19 September 2017 at 17:11, Christian Gagneraud <chgans at gmail.com> wrote:
> On 18 September 2017 at 14:52, Christian Gagneraud <chgans at gmail.com> wrote:
>> On 18 September 2017 at 08:25, Milian Wolff <milian.wolff at kdab.com> wrote:
>> [...]
>>>>
>>>> I'm reading this right [1] now, it's called "Cheating the ELF -
>>>> Subversive Dynamic Linking to Libraries".
>>>> AFAIU, he's talking about manipulation of the PLT of an ELF image.
>>>> Which is, I think, what i would like to achieve: replace a symbol with
>>>> another one of my choice, and still be able to call the original
>>>> symbol.
>>>> Now, this does not seem easy....
>>>
>>> You can have a look at the heaptrack injector code, which does just that.
>>
>> Yes, it is very interesting indeed, thanks for the pointer!
>
> Using this technique i was able to subsitute Qt's dynamic symbols (eg,
> qt_startup_hook) in a simple Qt application.
> And i now understand what this QtCore.dyn file is all about! ;)
>
> Using the Loadable program segment, i can as well wrap any Qt function
> used by the program (QObject::EventFilter, ...).

Hi Milian,

This makes me think that heaptrack doesn't track memory related
symbols directly imported by the program itself. It does track only
malloc/free made by loaded shared objects.... Am I missing something?

Due to https://github.com/KDE/heaptrack/blob/master/src/track/heaptrack_inject.cpp#L269


Chris

>
> But i would like to do the same on the program own code.... which is a
> different story.
>
> Chris