1 files changed, 29 insertions, 19 deletions

diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 0619a1cbbfbe..e172f182b65c 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -571,11 +571,18 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf,
 			      size_t count, loff_t *ppos)
 
 {
-	struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
+	struct selinux_fs_info *fsi;
 	struct selinux_load_state load_state;
 	ssize_t length;
 	void *data = NULL;
 
+	/* no partial writes */
+	if (*ppos)
+		return -EINVAL;
+	/* no empty policies */
+	if (!count)
+		return -EINVAL;
+
 	mutex_lock(&selinux_state.policy_mutex);
 
 	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
@@ -583,26 +590,22 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf,
 	if (length)
 		goto out;
 
-	/* No partial writes. */
-	length = -EINVAL;
-	if (*ppos != 0)
-		goto out;
-
-	length = -ENOMEM;
 	data = vmalloc(count);
-	if (!data)
+	if (!data) {
+		length = -ENOMEM;
 		goto out;
-
-	length = -EFAULT;
-	if (copy_from_user(data, buf, count) != 0)
+	}
+	if (copy_from_user(data, buf, count) != 0) {
+		length = -EFAULT;
 		goto out;
+	}
 
 	length = security_load_policy(data, count, &load_state);
 	if (length) {
 		pr_warn_ratelimited("SELinux: failed to load policy\n");
 		goto out;
 	}
-
+	fsi = file_inode(file)->i_sb->s_fs_info;
 	length = sel_make_policy_nodes(fsi, load_state.policy);
 	if (length) {
 		pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
@@ -611,13 +614,12 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf,
 	}
 
 	selinux_policy_commit(&load_state);
-
 	length = count;
-
 	audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 		"auid=%u ses=%u lsm=selinux res=1",
 		from_kuid(&init_user_ns, audit_get_loginuid(current)),
 		audit_get_sessionid(current));
+
 out:
 	mutex_unlock(&selinux_state.policy_mutex);
 	vfree(data);
@@ -2123,7 +2125,6 @@ static struct file_system_type sel_fs_type = {
 	.kill_sb	= sel_kill_sb,
 };
 
-static struct vfsmount *selinuxfs_mount __ro_after_init;
 struct path selinux_null __ro_after_init;
 
 static int __init init_sel_fs(void)
@@ -2145,20 +2146,29 @@ static int __init init_sel_fs(void)
 		return err;
 	}
 
-	selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
-	if (IS_ERR(selinuxfs_mount)) {
+	selinux_null.mnt = kern_mount(&sel_fs_type);
+	if (IS_ERR(selinux_null.mnt)) {
 		pr_err("selinuxfs:  could not mount!\n");
-		err = PTR_ERR(selinuxfs_mount);
-		selinuxfs_mount = NULL;
+		err = PTR_ERR(selinux_null.mnt);
+		selinux_null.mnt = NULL;
+		return err;
 	}
+
 	selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
 						&null_name);
 	if (IS_ERR(selinux_null.dentry)) {
 		pr_err("selinuxfs:  could not lookup null!\n");
 		err = PTR_ERR(selinux_null.dentry);
 		selinux_null.dentry = NULL;
+		return err;
 	}
 
+	/*
+	 * Try to pre-allocate the status page, so the sequence number of the
+	 * initial policy load can be stored.
+	 */
+	(void) selinux_kernel_status_page();
+
 	return err;
 }