smackfs: Added check catlen

  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>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index 4b58526450d492fc0ce8b8af6388b96e0bbe782d..5590eaad241bbc67f89da256f756c8443fad1c66 100644 (file)
--- 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;