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Message-ID: <fd0888a4-099c-95fe-7e20-82be1489061f@kernel.org>
Date:   Mon, 25 Jul 2022 15:34:56 +0200
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Subject: Re: [PATCH] rtla: fix double free
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To:     Andreas Schwab <schwab@suse.de>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org
References: <mvmzggxl4n1.fsf@suse.de>
From:   Daniel Bristot de Oliveira <bristot@kernel.org>
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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?

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

Why am I asking? because if it is a double-free bug, we need to add the "Fixes:"
tag, otherwise, we can think about a Subject that better describes the patch,  like:

"rtla: Do not call trace_instance_destroy() twice on error"

Also, after the "subsystem:," i.e., "rlta:" we need to use capital: e.g.,

"rtla: Fix double free"

Anyways, I see that the code makes sense. I am just trying to improve the
description.

Thanks!
-- Daniel