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Message-ID: <458d93ba-ff78-54e7-5639-bee89e61ce19@quicinc.com>
Date:   Thu, 11 Aug 2022 16:48:25 +0800
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Subject: Re: [PATCH v2] tracing: react to error return from
 traceprobe_parse_event_name()
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To:     Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Tom Zanussi <zanussi@kernel.org>
CC:     <kernel-janitors@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20220811071734.20700-1-lukas.bulwahn@gmail.com>
From:   Linyu Yuan <quic_linyyuan@quicinc.com>
In-Reply-To: <20220811071734.20700-1-lukas.bulwahn@gmail.com>
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Precedence: bulk

thanks,

Acked-by: Linyu Yuan <quic_linyyuan@quicinc.com>


On 8/11/2022 3:17 PM, Lukas Bulwahn wrote:
> The function traceprobe_parse_event_name() may set the first two function
> arguments to a non-null value and still return -EINVAL to indicate an
> unsuccessful completion of the function. Hence, it is not sufficient to
> just check the result of the two function arguments for being not null,
> but the return value also needs to be checked.
>
> Commit 95c104c378dc ("tracing: Auto generate event name when creating a
> group of events") changed the error-return-value checking of the second
> traceprobe_parse_event_name() invocation in __trace_eprobe_create() and
> removed checking the return value to jump to the error handling case.
>
> Reinstate using the return value in the error-return-value checking.
>
> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
> ---
>   kernel/trace/trace_eprobe.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
> index 4a0e9d927443..550671985fd1 100644
> --- a/kernel/trace/trace_eprobe.c
> +++ b/kernel/trace/trace_eprobe.c
> @@ -883,7 +883,7 @@ static int __trace_eprobe_create(int argc, const char *argv[])
>   	trace_probe_log_set_index(1);
>   	sys_event = argv[1];
>   	ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2, 0);
> -	if (!sys_event || !sys_name) {
> +	if (ret || !sys_event || !sys_name) {
>   		trace_probe_log_err(0, NO_EVENT_INFO);
>   		goto parse_error;
>   	}