Re: [PATCH] rtla: fix double free

[Andreas Schwab]

On Jul 25 2022, Daniel Bristot de Oliveira wrote:

> Hi Andreas
>
> On 7/25/22 15:10, Andreas Schwab wrote:
>> Don't call trace_instance_destroy in trace_instance_init when it fails,
>> this is done by the caller.
>
> Regarding the Subject, are you seeing a double-free error, or it is just an
> optimization?

A double free nowadays is almost always an error, due to better malloc
checking.

> AFAICS, trace_instance_destroy() checks the pointers before calling free().

That doesn't help when the pointer is not cleared afterwards.  Do you
prefer that?

> Why am I asking? because if it is a double-free bug, we need to add the "Fixes:"
> tag,

It's the first time I tried running rtla, so I don't know whether it is
a regression, but from looking at the history it appears to have been
introduced already in commit 0605bf009f18 ("rtla: Add osnoise tool")

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