[PATCH] ubifs: prefer kstrtobool_from_user() over custom helper

[Zhihao Cheng]

在 2026/4/2 16:13, Dmitry Antipov 写道:
> Adjust 'dfs_file_write()' and 'dfs_global_file_write()' to prefer generic
> 'kstrtobool_from_user()' over an ad-hoc 'interpret_user_input()' helper,
> thus making the latter not needed anymore.
> 
> Signed-off-by: Dmitry Antipov <dmantipov at yandex.ru>
> ---
>   fs/ubifs/debug.c | 44 ++++++++++----------------------------------
>   1 file changed, 10 insertions(+), 34 deletions(-)
> 

Reviewed-by: Zhihao Cheng <chengzhihao1 at huawei.com>
> diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
> index 160c16aa7b6e..252cf82012cf 100644
> --- a/fs/ubifs/debug.c
> +++ b/fs/ubifs/debug.c
> @@ -2732,39 +2732,14 @@ static ssize_t dfs_file_read(struct file *file, char __user *u, size_t count,
>   	return provide_user_output(val, u, count, ppos);
>   }
>   
> -/**
> - * interpret_user_input - interpret user debugfs file input.
> - * @u: user-provided buffer with the input
> - * @count: buffer size
> - *
> - * This is a helper function which interpret user input to a boolean UBIFS
> - * debugfs file. Returns %0 or %1 in case of success and a negative error code
> - * in case of failure.
> - */
> -static int interpret_user_input(const char __user *u, size_t count)
> -{
> -	size_t buf_size;
> -	char buf[8];
> -
> -	buf_size = min_t(size_t, count, (sizeof(buf) - 1));
> -	if (copy_from_user(buf, u, buf_size))
> -		return -EFAULT;
> -
> -	if (buf[0] == '1')
> -		return 1;
> -	else if (buf[0] == '0')
> -		return 0;
> -
> -	return -EINVAL;
> -}
> -
>   static ssize_t dfs_file_write(struct file *file, const char __user *u,
>   			      size_t count, loff_t *ppos)
>   {
>   	struct ubifs_info *c = file->private_data;
>   	struct ubifs_debug_info *d = c->dbg;
>   	struct dentry *dent = file->f_path.dentry;
> -	int val;
> +	bool val;
> +	int ret;
>   
>   	if (file->f_path.dentry == d->dfs_dump_lprops) {
>   		ubifs_dump_lprops(c);
> @@ -2781,9 +2756,9 @@ static ssize_t dfs_file_write(struct file *file, const char __user *u,
>   		return count;
>   	}
>   
> -	val = interpret_user_input(u, count);
> -	if (val < 0)
> -		return val;
> +	ret = kstrtobool_from_user(u, count, &val);
> +	if (unlikely(ret))
> +		return ret;
>   
>   	if (dent == d->dfs_chk_gen)
>   		d->chk_gen = val;
> @@ -2926,11 +2901,12 @@ static ssize_t dfs_global_file_write(struct file *file, const char __user *u,
>   				     size_t count, loff_t *ppos)
>   {
>   	struct dentry *dent = file->f_path.dentry;
> -	int val;
> +	bool val;
> +	int ret;
>   
> -	val = interpret_user_input(u, count);
> -	if (val < 0)
> -		return val;
> +	ret = kstrtobool_from_user(u, count, &val);
> +	if (unlikely(ret))
> +		return ret;
>   
>   	if (dent == dfs_chk_gen)
>   		ubifs_dbg.chk_gen = val;
>