Re: [PATCH v2 4/7] tracing: Add synthetic event error logging

[Steven Rostedt]

On Mon, 12 Oct 2020 15:18:06 -0500
Tom Zanussi <zanussi@xxxxxxxxxx> wrote:

> +static char last_cmd[MAX_FILTER_STR_VAL];
> +
> +static int errpos(const char *str)
> +{
> +	return err_pos(last_cmd, str);
> +}
> +
> +static void last_cmd_set(char *str)
> +{
> +	if (!str)
> +		return;
> +
> +	strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1);

If I understand strncat() correctly, it will add 'n' + 1 bytes from str
to last_cmd. That is, I think you want:

	strncat(last_cmd, str, MAX_FILTER_STR_VAL - (strlen(last_cmd) + 1));

-- Steve


> +}
> +
> +static void synth_err(u8 err_type, u8 err_pos)
> +{
> +	tracing_log_err(NULL, "synthetic_events", last_cmd, err_text,
> +			err_type, err_pos);
> +}
> +
> +static void synth_err_clear(void)
> +{
> +	last_cmd[0] = '\0';
> +}
> +