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Date: Fri, 26 Apr 2024 18:45:21 +0200
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To: Masami Hiramatsu <mhiramat@kernel.org>, lumingyindetect@126.com,
 linux-trace-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>,
 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
 Steven Rostedt <rostedt@goodmis.org>
References: <20240427001843.84a3d367d3654b624c09defe@kernel.org>
Subject: Re: tracing/probes: Fix a memory leak in
 traceprobe_parse_probe_arg_body()
Content-Language: en-GB
From: Markus Elfring <Markus.Elfring@web.de>
In-Reply-To: <20240427001843.84a3d367d3654b624c09defe@kernel.org>
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=E2=80=A6
> ----
>  If traceprobe_parse_probe_arg_body() fails to allocate 'parg->fmt', it
>  jumps to 'out' instead of 'fail' by mistake. In the result, in this
>  case the 'tmp' buffer is not freed and leaks its memory.
>
>  Fix it by jumping to 'fail' in that case.
> ----
=E2=80=A6

How do you think about another approach for a more desirable change descri=
ption?

   If traceprobe_parse_probe_arg_body() failed to allocate the object =E2=
=80=9Cparg->fmt=E2=80=9D,
   it jumps to the label =E2=80=9Cout=E2=80=9D instead of =E2=80=9Cfail=E2=
=80=9D by mistake.
   In the result, the buffer =E2=80=9Ctmp=E2=80=9D is not freed in this ca=
se and leaks its memory.

   Thus jump to the label =E2=80=9Cfail=E2=80=9D in that case (so that the=
 exception handling
   will be improved another bit).


Regards,
Markus