Re: [PATCH 1/3] securityfs: Append line feed to /sys/kernel/security/lsm

[Casey Schaufler]

On 5/5/2022 6:22 AM, Wang Weiyang wrote:
> There is no LF in /sys/kerne/security/lsm output. It is a little weird,
> so append LF to it.

NAK: The existing behavior is consistent with long standing LSM convention.

> Example:
>
> / # cat /sys/kernel/security/lsm
> capability,selinux/ #
>
> Signed-off-by: Wang Weiyang <wangweiyang2@xxxxxxxxxx>
> ---
>   security/inode.c | 16 ++++++++++++++--
>   1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/security/inode.c b/security/inode.c
> index 6c326939750d..bfd5550fa129 100644
> --- a/security/inode.c
> +++ b/security/inode.c
> @@ -318,8 +318,20 @@ static struct dentry *lsm_dentry;
>   static ssize_t lsm_read(struct file *filp, char __user *buf, size_t count,
>   			loff_t *ppos)
>   {
> -	return simple_read_from_buffer(buf, count, ppos, lsm_names,
> -		strlen(lsm_names));
> +	char *tmp;
> +	ssize_t len = strlen(lsm_names);
> +	ssize_t rc;
> +
> +	tmp = kmalloc(len + 2, GFP_KERNEL);
> +	if (!tmp)
> +		return -ENOMEM;
> +
> +	scnprintf(tmp, len + 2, "%s\n", lsm_names);
> +	rc = simple_read_from_buffer(buf, count, ppos, tmp, strlen(tmp));
> +
> +	kfree(tmp);
> +
> +	return rc;
>   }
>   
>   static const struct file_operations lsm_ops = {