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Date:   Sun, 8 Jan 2023 01:01:24 +0900
From:   Masami Hiramatsu (Google) <mhiramat@kernel.org>
To:     Quanfa Fu <quanfafu@gmail.com>
Cc:     rostedt@goodmis.org, linux-kernel@vger.kernel.org,
        linux-trace-kernel@vger.kernel.org
Subject: Re: [PATCH] tracing/eprobe: Replace kzalloc with kmalloc
Message-Id: <20230108010124.96e4ceb68b8dfb8e291f501d@kernel.org>
In-Reply-To: <20230107034557.1156022-1-quanfafu@gmail.com>
References: <20230107034557.1156022-1-quanfafu@gmail.com>
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On Sat,  7 Jan 2023 11:45:57 +0800
Quanfa Fu <quanfafu@gmail.com> wrote:

> Since this memory will be filled soon below, I feel that there is
> no need for a memory of all zeros here. 'snprintf' does not return
> negative num according to ISO C99, so I feel that no judgment is
> needed here.
> 
> No functional change intended.
> 

Ah, good catch. I didn't notice that snprintf() doesn't return
error code. (I confirmed that the linux internal snprintf() also
doesn't return the error code)

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thank you!

> Signed-off-by: Quanfa Fu <quanfafu@gmail.com>
> ---
>  kernel/trace/trace_eprobe.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
> index 352b65e2b910..cd1d271a74e7 100644
> --- a/kernel/trace/trace_eprobe.c
> +++ b/kernel/trace/trace_eprobe.c
> @@ -917,15 +917,13 @@ static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const ch
>  	for (i = 0; i < argc; i++)
>  		len += strlen(argv[i]) + 1;
>  
> -	ep->filter_str = kzalloc(len, GFP_KERNEL);
> +	ep->filter_str = kmalloc(len, GFP_KERNEL);
>  	if (!ep->filter_str)
>  		return -ENOMEM;
>  
>  	p = ep->filter_str;
>  	for (i = 0; i < argc; i++) {
>  		ret = snprintf(p, len, "%s ", argv[i]);
> -		if (ret < 0)
> -			goto error;
>  		if (ret > len) {
>  			ret = -E2BIG;
>  			goto error;
> -- 
> 2.31.1
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>