#define SEQ_READ_FINISHED 1
-/*
- * Disable concurrent writing open() operations
- */
-static struct semaphore smack_write_sem;
-
/*
* Values for parsing cipso rules
* SMK_DIGITLEN: Length of a digit field in a rule.
- * SMK_CIPSOMEN: Minimum possible cipso rule length.
+ * SMK_CIPSOMIN: Minimum possible cipso rule length.
+ * SMK_CIPSOMAX: Maximum possible cipso rule length.
*/
#define SMK_DIGITLEN 4
-#define SMK_CIPSOMIN (SMK_MAXLEN + 2 * SMK_DIGITLEN)
+#define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN)
+#define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN)
+
+/*
+ * Values for parsing MAC rules
+ * SMK_ACCESS: Maximum possible combination of access permissions
+ * SMK_ACCESSLEN: Maximum length for a rule access field
+ * SMK_LOADLEN: Smack rule length
+ */
+#define SMK_ACCESS "rwxa"
+#define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
+#define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
+
/*
* Seq_file read operations for /smack/load
*/
static int smk_open_load(struct inode *inode, struct file *file)
{
- if ((file->f_flags & O_ACCMODE) == O_RDONLY)
- return seq_open(file, &load_seq_ops);
-
- if (down_interruptible(&smack_write_sem))
- return -ERESTARTSYS;
-
- return 0;
-}
-
-/**
- * smk_release_load - release() for /smack/load
- * @inode: inode structure representing file
- * @file: "load" file pointer
- *
- * For a reading session, use the seq_file release
- * implementation.
- * Otherwise, we are at the end of a writing session so
- * clean everything up.
- */
-static int smk_release_load(struct inode *inode, struct file *file)
-{
- if ((file->f_flags & O_ACCMODE) == O_RDONLY)
- return seq_release(inode, file);
-
- up(&smack_write_sem);
- return 0;
+ return seq_open(file, &load_seq_ops);
}
/**
* The format is exactly:
* char subject[SMK_LABELLEN]
* char object[SMK_LABELLEN]
- * char access[SMK_ACCESSKINDS]
+ * char access[SMK_ACCESSLEN]
*
- * Anything following is commentary and ignored.
- *
- * writes must be SMK_LABELLEN+SMK_LABELLEN+4 bytes.
+ * writes must be SMK_LABELLEN+SMK_LABELLEN+SMK_ACCESSLEN bytes.
*/
-#define MINIMUM_LOAD (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSKINDS)
-
static ssize_t smk_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return -EPERM;
if (*ppos != 0)
return -EINVAL;
- if (count < MINIMUM_LOAD)
+ if (count != SMK_LOADLEN)
return -EINVAL;
data = kzalloc(count, GFP_KERNEL);
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_load,
- .release = smk_release_load,
+ .release = seq_release,
};
/**
return -EPERM;
if (*ppos != 0)
return -EINVAL;
- if (count <= SMK_CIPSOMIN)
+ if (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX)
return -EINVAL;
data = kzalloc(count + 1, GFP_KERNEL);
if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
goto out;
- if (count <= (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
+ if (count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
goto out;
memset(mapcatset, 0, sizeof(mapcatset));
*
* register the smackfs
*
- * Returns 0 unless the registration fails.
+ * Do not register smackfs if Smack wasn't enabled
+ * on boot. We can not put this method normally under the
+ * smack_init() code path since the security subsystem get
+ * initialized before the vfs caches.
+ *
+ * Returns true if we were not chosen on boot or if
+ * we were chosen and filesystem registration succeeded.
*/
static int __init init_smk_fs(void)
{
int err;
+ if (!security_module_enable(&smack_ops))
+ return 0;
+
err = register_filesystem(&smk_fs_type);
if (!err) {
smackfs_mount = kern_mount(&smk_fs_type);
}
}
- sema_init(&smack_write_sem, 1);
smk_cipso_doi();
smk_unlbl_ambient(NULL);