Re: [PATCH 2/3] ubifs: Don't parse authentication mount options in remount process

[Sascha Hauer <s.hauer@pengutronix.de>]

On Tue, Sep 29, 2020 at 08:45:30PM +0800, Zhihao Cheng wrote:
> There is no need to dump authentication options while remounting,
> because authentication initialization can only be doing once in
> the first mount process. Dumping authentication mount options in
> remount process may cause memory leak if UBIFS has already been
> mounted with old authentication mount options.
> 
> Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
> Cc: <stable@vger.kernel.org>  # 4.20+
> Fixes: d8a22773a12c6d7 ("ubifs: Enable authentication support")

Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>

Sascha

> ---
>  fs/ubifs/super.c | 18 ++++++++++++------
>  1 file changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
> index 6f85cd618766..9796f5df2f7f 100644
> --- a/fs/ubifs/super.c
> +++ b/fs/ubifs/super.c
> @@ -1110,14 +1110,20 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options,
>  			break;
>  		}
>  		case Opt_auth_key:
> -			c->auth_key_name = kstrdup(args[0].from, GFP_KERNEL);
> -			if (!c->auth_key_name)
> -				return -ENOMEM;
> +			if (!is_remount) {
> +				c->auth_key_name = kstrdup(args[0].from,
> +								GFP_KERNEL);
> +				if (!c->auth_key_name)
> +					return -ENOMEM;
> +			}
>  			break;
>  		case Opt_auth_hash_name:
> -			c->auth_hash_name = kstrdup(args[0].from, GFP_KERNEL);
> -			if (!c->auth_hash_name)
> -				return -ENOMEM;
> +			if (!is_remount) {
> +				c->auth_hash_name = kstrdup(args[0].from,
> +								GFP_KERNEL);
> +				if (!c->auth_hash_name)
> +					return -ENOMEM;
> +			}
>  			break;
>  		case Opt_ignore:
>  			break;
> -- 
> 2.25.4
> 
> 

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