Message-ID: <d0bff7d8-5d29-8841-908e-6b83932a4968@schaufler-ca.com>
Date:   Mon, 30 Jan 2023 09:37:27 -0800
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Subject: Re: [PATCH] smackfs: Added check catlen
Content-Language: en-US
To:     Denis Arefev <arefev@swemel.ru>
Cc:     Paul Moore <paul@paul-moore.com>, James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, trufanov@swemel.ru, vfh@swemel.ru,
        casey@schaufler-ca.com
References: <20230124105037.23108-1-arefev@swemel.ru>
From:   Casey Schaufler <casey@schaufler-ca.com>
In-Reply-To: <20230124105037.23108-1-arefev@swemel.ru>
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On 1/24/2023 2:50 AM, Denis Arefev wrote:
>   If the catlen is 0, the memory for the netlbl_lsm_catmap
>   structure must be allocated anyway, otherwise the check of
>   such rules is not completed correctly.
>
> Signed-off-by: Denis Arefev <arefev@swemel.ru>

Added to smack-next. Thank you.

> ---
>  security/smack/smackfs.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
> index 4b58526450d4..d45f4395a6ce 100644
> --- a/security/smack/smackfs.c
> +++ b/security/smack/smackfs.c
> @@ -830,7 +830,7 @@ static int smk_open_cipso(struct inode *inode, struct file *file)
>  static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
>  				size_t count, loff_t *ppos, int format)
>  {
> -	struct netlbl_lsm_catmap *old_cat;
> +	struct netlbl_lsm_catmap *old_cat, *new_cat = NULL;
>  	struct smack_known *skp;
>  	struct netlbl_lsm_secattr ncats;
>  	char mapcatset[SMK_CIPSOLEN];
> @@ -917,8 +917,19 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
>  
>  		smack_catset_bit(cat, mapcatset);
>  	}
> -
> -	rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
> +	ncats.flags = 0;
> +	if (catlen == 0) {
> +		ncats.attr.mls.cat = NULL;
> +		ncats.attr.mls.lvl = maplevel;
> +		new_cat = netlbl_catmap_alloc(GFP_ATOMIC);
> +		if (new_cat)
> +			new_cat->next = ncats.attr.mls.cat;
> +		ncats.attr.mls.cat = new_cat;
> +		skp->smk_netlabel.flags &= ~(1U << 3);
> +		rc = 0;
> +	} else {
> +		rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
> +	}
>  	if (rc >= 0) {
>  		old_cat = skp->smk_netlabel.attr.mls.cat;
>  		skp->smk_netlabel.attr.mls.cat = ncats.attr.mls.cat;