Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs mount API prep from Al Viro:
"Mount API prereqs.

Mostly that's LSM mount options cleanups. There are several minor
fixes in there, but nothing earth-shattering (leaks on failure exits,
mostly)"

* 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (27 commits)
mount_fs: suppress MAC on MS_SUBMOUNT as well as MS_KERNMOUNT
smack: rewrite smack_sb_eat_lsm_opts()
smack: get rid of match_token()
smack: take the guts of smack_parse_opts_str() into a new helper
LSM: new method: ->sb_add_mnt_opt()
selinux: rewrite selinux_sb_eat_lsm_opts()
selinux: regularize Opt_... names a bit
selinux: switch away from match_token()
selinux: new helper - selinux_add_opt()
LSM: bury struct security_mnt_opts
smack: switch to private smack_mnt_opts
selinux: switch to private struct selinux_mnt_opts
LSM: hide struct security_mnt_opts from any generic code
selinux: kill selinux_sb_get_mnt_opts()
LSM: turn sb_eat_lsm_opts() into a method
nfs_remount(): don't leak, don't ignore LSM options quietly
btrfs: sanitize security_mnt_opts use
selinux; don't open-code a loop in sb_finish_set_opts()
LSM: split ->sb_set_mnt_opts() out of ->sb_kern_mount()
new helper: security_sb_eat_lsm_opts()
...

arch/arc/kernel/setup.c

···
 #include <linux/of_fdt.h>
 #include <linux/of.h>
 #include <linux/cache.h>
+#include <uapi/linux/mount.h>
 #include <asm/sections.h>
 #include <asm/arcregs.h>
 #include <asm/tlb.h>

arch/arm/kernel/atags_parse.c

···
 #include <linux/root_dev.h>
 #include <linux/screen_info.h>
 #include <linux/memblock.h>
+#include <uapi/linux/mount.h>
 
 #include <asm/setup.h>
 #include <asm/system_info.h>

arch/sh/kernel/setup.c

···
 #include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/uaccess.h>
+#include <uapi/linux/mount.h>
 #include <asm/io.h>
 #include <asm/page.h>
 #include <asm/elf.h>

arch/sparc/kernel/setup_32.c

···
 #include <linux/kdebug.h>
 #include <linux/export.h>
 #include <linux/start_kernel.h>
+#include <uapi/linux/mount.h>
 
 #include <asm/io.h>
 #include <asm/processor.h>

arch/sparc/kernel/setup_64.c

···
 #include <linux/module.h>
 #include <linux/start_kernel.h>
 #include <linux/memblock.h>
+#include <uapi/linux/mount.h>
 
 #include <asm/io.h>
 #include <asm/processor.h>

arch/x86/kernel/setup.c

···
 #include <linux/kvm_para.h>
 #include <linux/dma-contiguous.h>
 #include <xen/xen.h>
+#include <uapi/linux/mount.h>
 
 #include <linux/errno.h>
 #include <linux/kernel.h>

drivers/base/devtmpfs.c

···
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/kthread.h>
+#include <uapi/linux/mount.h>
 #include "base.h"
 
 static struct task_struct *thread;

fs/btrfs/ctree.h

···
 	struct mutex unused_bg_unpin_mutex;
 	struct mutex delete_unused_bgs_mutex;
 
-	/* For btrfs to record security options */
-	struct security_mnt_opts security_opts;
-
 	/*
 	 * Chunks that can't be freed yet (under a trim/discard operation)
 	 * and will be latter freed. Protected by fs_info->chunk_mutex.
···
 	kfree(fs_info->free_space_root);
 	kfree(fs_info->super_copy);
 	kfree(fs_info->super_for_commit);
-	security_free_mnt_opts(&fs_info->security_opts);
 	kvfree(fs_info);
 }
 

fs/btrfs/super.c

···
 	return root;
 }
 
-static int parse_security_options(char *orig_opts,
-				  struct security_mnt_opts *sec_opts)
-{
-	char *secdata = NULL;
-	int ret = 0;
-
-	secdata = alloc_secdata();
-	if (!secdata)
-		return -ENOMEM;
-	ret = security_sb_copy_data(orig_opts, secdata);
-	if (ret) {
-		free_secdata(secdata);
-		return ret;
-	}
-	ret = security_sb_parse_opts_str(secdata, sec_opts);
-	free_secdata(secdata);
-	return ret;
-}
-
-static int setup_security_options(struct btrfs_fs_info *fs_info,
-				  struct super_block *sb,
-				  struct security_mnt_opts *sec_opts)
-{
-	int ret = 0;
-
-	/*
-	 * Call security_sb_set_mnt_opts() to check whether new sec_opts
-	 * is valid.
-	 */
-	ret = security_sb_set_mnt_opts(sb, sec_opts, 0, NULL);
-	if (ret)
-		return ret;
-
-#ifdef CONFIG_SECURITY
-	if (!fs_info->security_opts.num_mnt_opts) {
-		/* first time security setup, copy sec_opts to fs_info */
-		memcpy(&fs_info->security_opts, sec_opts, sizeof(*sec_opts));
-	} else {
-		/*
-		 * Since SELinux (the only one supporting security_mnt_opts)
-		 * does NOT support changing context during remount/mount of
-		 * the same sb, this must be the same or part of the same
-		 * security options, just free it.
-		 */
-		security_free_mnt_opts(sec_opts);
-	}
-#endif
-	return ret;
-}
-
 /*
  * Find a superblock for the given device / mount point.
  *
···
 	struct btrfs_device *device = NULL;
 	struct btrfs_fs_devices *fs_devices = NULL;
 	struct btrfs_fs_info *fs_info = NULL;
-	struct security_mnt_opts new_sec_opts;
+	void *new_sec_opts = NULL;
 	fmode_t mode = FMODE_READ;
 	int error = 0;
 
 	if (!(flags & SB_RDONLY))
 		mode |= FMODE_WRITE;
 
-	security_init_mnt_opts(&new_sec_opts);
 	if (data) {
-		error = parse_security_options(data, &new_sec_opts);
+		error = security_sb_eat_lsm_opts(data, &new_sec_opts);
 		if (error)
 			return ERR_PTR(error);
 	}
···
 
 	fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
 	fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
-	security_init_mnt_opts(&fs_info->security_opts);
 	if (!fs_info->super_copy || !fs_info->super_for_commit) {
 		error = -ENOMEM;
 		goto error_fs_info;
···
 		btrfs_sb(s)->bdev_holder = fs_type;
 		error = btrfs_fill_super(s, fs_devices, data);
 	}
+	if (!error)
+		error = security_sb_set_mnt_opts(s, new_sec_opts, 0, NULL);
+	security_free_mnt_opts(&new_sec_opts);
 	if (error) {
 		deactivate_locked_super(s);
-		goto error_sec_opts;
-	}
-
-	fs_info = btrfs_sb(s);
-	error = setup_security_options(fs_info, s, &new_sec_opts);
-	if (error) {
-		deactivate_locked_super(s);
-		goto error_sec_opts;
+		return ERR_PTR(error);
 	}
 
 	return dget(s->s_root);
···
 	btrfs_remount_prepare(fs_info);
 
 	if (data) {
-		struct security_mnt_opts new_sec_opts;
+		void *new_sec_opts = NULL;
 
-		security_init_mnt_opts(&new_sec_opts);
-		ret = parse_security_options(data, &new_sec_opts);
+		ret = security_sb_eat_lsm_opts(data, &new_sec_opts);
+		if (!ret)
+			ret = security_sb_remount(sb, new_sec_opts);
+		security_free_mnt_opts(&new_sec_opts);
 		if (ret)
 			goto restore;
-		ret = setup_security_options(fs_info, sb,
-					     &new_sec_opts);
-		if (ret) {
-			security_free_mnt_opts(&new_sec_opts);
-			goto restore;
-		}
 	}
 
 	ret = btrfs_parse_options(fs_info, data, *flags);

fs/exofs/super.c

···
 /*
  * Read the superblock from the OSD and fill in the fields
  */
-static int exofs_fill_super(struct super_block *sb, void *data, int silent)
+static int exofs_fill_super(struct super_block *sb,
+				struct exofs_mountopt *opts,
+				struct exofs_sb_info *sbi,
+				int silent)
 {
 	struct inode *root;
-	struct exofs_mountopt *opts = data;
-	struct exofs_sb_info *sbi;	/*extended info                  */
 	struct osd_dev *od;		/* Master device                 */
 	struct exofs_fscb fscb;		/*on-disk superblock info        */
 	struct ore_comp comp;
 	unsigned table_count;
 	int ret;
-
-	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
-	if (!sbi)
-		return -ENOMEM;
 
 	/* use mount options to fill superblock */
 	if (opts->is_osdname) {
···
 			  int flags, const char *dev_name,
 			  void *data)
 {
+	struct super_block *s;
 	struct exofs_mountopt opts;
+	struct exofs_sb_info *sbi;
 	int ret;
 
 	ret = parse_options(data, &opts);
···
 		return ERR_PTR(ret);
 	}
 
+	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
+	if (!sbi) {
+		kfree(opts.dev_name);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	s = sget(type, NULL, set_anon_super, flags, NULL);
+
+	if (IS_ERR(s)) {
+		kfree(opts.dev_name);
+		kfree(sbi);
+		return ERR_CAST(s);
+	}
+
 	if (!opts.dev_name)
 		opts.dev_name = dev_name;
-	return mount_nodev(type, flags, &opts, exofs_fill_super);
+
+
+	ret = exofs_fill_super(s, &opts, sbi, flags & SB_SILENT ? 1 : 0);
+	if (ret) {
+		deactivate_locked_super(s);
+		return ERR_PTR(ret);
+	}
+	s->s_flags |= SB_ACTIVE;
+	return dget(s->s_root);
 }
 
 /*

fs/namespace.c

···
 #include <linux/memblock.h>
 #include <linux/task_work.h>
 #include <linux/sched/task.h>
+#include <uapi/linux/mount.h>
 
 #include "pnode.h"
 #include "internal.h"
···
  * mnt_want/drop_write() will _keep_ the filesystem
  * r/w.
  */
-int __mnt_is_readonly(struct vfsmount *mnt)
+bool __mnt_is_readonly(struct vfsmount *mnt)
 {
-	if (mnt->mnt_flags & MNT_READONLY)
-		return 1;
-	if (sb_rdonly(mnt->mnt_sb))
-		return 1;
-	return 0;
+	return (mnt->mnt_flags & MNT_READONLY) || sb_rdonly(mnt->mnt_sb);
 }
 EXPORT_SYMBOL_GPL(__mnt_is_readonly);
 
···
 	return ret;
 }
 
-static void __mnt_unmake_readonly(struct mount *mnt)
+static int __mnt_unmake_readonly(struct mount *mnt)
 {
 	lock_mount_hash();
 	mnt->mnt.mnt_flags &= ~MNT_READONLY;
 	unlock_mount_hash();
+	return 0;
 }
 
 int sb_prepare_remount_readonly(struct super_block *sb)
···
 	return err;
 }
 
-static int change_mount_flags(struct vfsmount *mnt, int ms_flags)
+/*
+ * Don't allow locked mount flags to be cleared.
+ *
+ * No locks need to be held here while testing the various MNT_LOCK
+ * flags because those flags can never be cleared once they are set.
+ */
+static bool can_change_locked_flags(struct mount *mnt, unsigned int mnt_flags)
 {
-	int error = 0;
-	int readonly_request = 0;
+	unsigned int fl = mnt->mnt.mnt_flags;
 
-	if (ms_flags & MS_RDONLY)
-		readonly_request = 1;
-	if (readonly_request == __mnt_is_readonly(mnt))
+	if ((fl & MNT_LOCK_READONLY) &&
+	    !(mnt_flags & MNT_READONLY))
+		return false;
+
+	if ((fl & MNT_LOCK_NODEV) &&
+	    !(mnt_flags & MNT_NODEV))
+		return false;
+
+	if ((fl & MNT_LOCK_NOSUID) &&
+	    !(mnt_flags & MNT_NOSUID))
+		return false;
+
+	if ((fl & MNT_LOCK_NOEXEC) &&
+	    !(mnt_flags & MNT_NOEXEC))
+		return false;
+
+	if ((fl & MNT_LOCK_ATIME) &&
+	    ((fl & MNT_ATIME_MASK) != (mnt_flags & MNT_ATIME_MASK)))
+		return false;
+
+	return true;
+}
+
+static int change_mount_ro_state(struct mount *mnt, unsigned int mnt_flags)
+{
+	bool readonly_request = (mnt_flags & MNT_READONLY);
+
+	if (readonly_request == __mnt_is_readonly(&mnt->mnt))
 		return 0;
 
 	if (readonly_request)
-		error = mnt_make_readonly(real_mount(mnt));
-	else
-		__mnt_unmake_readonly(real_mount(mnt));
-	return error;
+		return mnt_make_readonly(mnt);
+
+	return __mnt_unmake_readonly(mnt);
+}
+
+/*
+ * Update the user-settable attributes on a mount.  The caller must hold
+ * sb->s_umount for writing.
+ */
+static void set_mount_attributes(struct mount *mnt, unsigned int mnt_flags)
+{
+	lock_mount_hash();
+	mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK;
+	mnt->mnt.mnt_flags = mnt_flags;
+	touch_mnt_namespace(mnt->mnt_ns);
+	unlock_mount_hash();
+}
+
+/*
+ * Handle reconfiguration of the mountpoint only without alteration of the
+ * superblock it refers to.  This is triggered by specifying MS_REMOUNT|MS_BIND
+ * to mount(2).
+ */
+static int do_reconfigure_mnt(struct path *path, unsigned int mnt_flags)
+{
+	struct super_block *sb = path->mnt->mnt_sb;
+	struct mount *mnt = real_mount(path->mnt);
+	int ret;
+
+	if (!check_mnt(mnt))
+		return -EINVAL;
+
+	if (path->dentry != mnt->mnt.mnt_root)
+		return -EINVAL;
+
+	if (!can_change_locked_flags(mnt, mnt_flags))
+		return -EPERM;
+
+	down_write(&sb->s_umount);
+	ret = change_mount_ro_state(mnt, mnt_flags);
+	if (ret == 0)
+		set_mount_attributes(mnt, mnt_flags);
+	up_write(&sb->s_umount);
+	return ret;
 }
 
 /*
···
 	int err;
 	struct super_block *sb = path->mnt->mnt_sb;
 	struct mount *mnt = real_mount(path->mnt);
+	void *sec_opts = NULL;
 
 	if (!check_mnt(mnt))
 		return -EINVAL;
···
 	if (path->dentry != path->mnt->mnt_root)
 		return -EINVAL;
 
-	/* Don't allow changing of locked mnt flags.
-	 *
-	 * No locks need to be held here while testing the various
-	 * MNT_LOCK flags because those flags can never be cleared
-	 * once they are set.
-	 */
-	if ((mnt->mnt.mnt_flags & MNT_LOCK_READONLY) &&
-	    !(mnt_flags & MNT_READONLY)) {
+	if (!can_change_locked_flags(mnt, mnt_flags))
 		return -EPERM;
-	}
-	if ((mnt->mnt.mnt_flags & MNT_LOCK_NODEV) &&
-	    !(mnt_flags & MNT_NODEV)) {
-		return -EPERM;
-	}
-	if ((mnt->mnt.mnt_flags & MNT_LOCK_NOSUID) &&
-	    !(mnt_flags & MNT_NOSUID)) {
-		return -EPERM;
-	}
-	if ((mnt->mnt.mnt_flags & MNT_LOCK_NOEXEC) &&
-	    !(mnt_flags & MNT_NOEXEC)) {
-		return -EPERM;
-	}
-	if ((mnt->mnt.mnt_flags & MNT_LOCK_ATIME) &&
-	    ((mnt->mnt.mnt_flags & MNT_ATIME_MASK) != (mnt_flags & MNT_ATIME_MASK))) {
-		return -EPERM;
-	}
 
-	err = security_sb_remount(sb, data);
+	if (data && !(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)) {
+		err = security_sb_eat_lsm_opts(data, &sec_opts);
+		if (err)
+			return err;
+	}
+	err = security_sb_remount(sb, sec_opts);
+	security_free_mnt_opts(&sec_opts);
 	if (err)
 		return err;
 
 	down_write(&sb->s_umount);
-	if (ms_flags & MS_BIND)
-		err = change_mount_flags(path->mnt, ms_flags);
-	else if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
-		err = -EPERM;
-	else
+	err = -EPERM;
+	if (ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) {
 		err = do_remount_sb(sb, sb_flags, data, 0);
-	if (!err) {
-		lock_mount_hash();
-		mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK;
-		mnt->mnt.mnt_flags = mnt_flags;
-		touch_mnt_namespace(mnt->mnt_ns);
-		unlock_mount_hash();
+		if (!err)
+			set_mount_attributes(mnt, mnt_flags);
 	}
 	up_write(&sb->s_umount);
 	return err;
···
 			    SB_LAZYTIME |
 			    SB_I_VERSION);
 
-	if (flags & MS_REMOUNT)
+	if ((flags & (MS_REMOUNT | MS_BIND)) == (MS_REMOUNT | MS_BIND))
+		retval = do_reconfigure_mnt(&path, mnt_flags);
+	else if (flags & MS_REMOUNT)
 		retval = do_remount(&path, flags, sb_flags, mnt_flags,
 				    data_page);
 	else if (flags & MS_BIND)

fs/nfs/internal.h

···
 		unsigned short		protocol;
 	} nfs_server;
 
-	struct security_mnt_opts lsm_opts;
+	void			*lsm_opts;
 	struct net		*net;
 };
 

fs/nfs/super.c

···
 		data->minorversion	= 0;
 		data->need_mount	= true;
 		data->net		= current->nsproxy->net_ns;
-		security_init_mnt_opts(&data->lsm_opts);
+		data->lsm_opts		= NULL;
 	}
 	return data;
 }
···
 static int nfs_parse_mount_options(char *raw,
 				   struct nfs_parsed_mount_data *mnt)
 {
-	char *p, *string, *secdata;
+	char *p, *string;
 	int rc, sloppy = 0, invalid_option = 0;
 	unsigned short protofamily = AF_UNSPEC;
 	unsigned short mountfamily = AF_UNSPEC;
···
 	}
 	dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 
-	secdata = alloc_secdata();
-	if (!secdata)
-		goto out_nomem;
-
-	rc = security_sb_copy_data(raw, secdata);
+	rc = security_sb_eat_lsm_opts(raw, &mnt->lsm_opts);
 	if (rc)
 		goto out_security_failure;
-
-	rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
-	if (rc)
-		goto out_security_failure;
-
-	free_secdata(secdata);
 
 	while ((p = strsep(&raw, ",")) != NULL) {
 		substring_t args[MAX_OPT_ARGS];
···
 	printk(KERN_INFO "NFS: not enough memory to parse option\n");
 	return 0;
 out_security_failure:
-	free_secdata(secdata);
 	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
 	return 0;
 }
···
 		if (data->context[0]){
 #ifdef CONFIG_SECURITY_SELINUX
 			int rc;
-			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
-			if (!opts_str)
-				return -ENOMEM;
-			strcpy(opts_str, "context=");
 			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
-			strcat(opts_str, &data->context[0]);
-			rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
-			kfree(opts_str);
+			rc = security_add_mnt_opt("context", data->context,
+					strlen(data->context), &args->lsm_opts);
 			if (rc)
 				return rc;
 #else
···
 					   options->version <= 6))))
 		return 0;
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	data = nfs_alloc_parsed_mount_data();
 	if (data == NULL)
 		return -ENOMEM;
 
···
 
 	/* compare new mount options with old ones */
 	error = nfs_compare_remount_data(nfss, data);
+	if (!error)
+		error = security_sb_remount(sb, data->lsm_opts);
 out:
-	kfree(data);
+	nfs_free_parsed_mount_data(data);
 	return error;
 }
 EXPORT_SYMBOL_GPL(nfs_remount);
···
 	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
 		kflags |= SECURITY_LSM_NATIVE_LABELS;
 
-	error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
+	error = security_sb_set_mnt_opts(s, mount_info->parsed->lsm_opts,
 						kflags, &kflags_out);
 	if (error)
 		goto err;

fs/pnode.c

···
 #include <linux/mount.h>
 #include <linux/fs.h>
 #include <linux/nsproxy.h>
+#include <uapi/linux/mount.h>
 #include "internal.h"
 #include "pnode.h"
 

fs/super.c

···
 #include <linux/fsnotify.h>
 #include <linux/lockdep.h>
 #include <linux/user_namespace.h>
+#include <uapi/linux/mount.h>
 #include "internal.h"
 
 static int thaw_super_locked(struct super_block *sb);
···
 {
 	struct dentry *root;
 	struct super_block *sb;
-	char *secdata = NULL;
 	int error = -ENOMEM;
+	void *sec_opts = NULL;
 
 	if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) {
-		secdata = alloc_secdata();
-		if (!secdata)
-			goto out;
-
-		error = security_sb_copy_data(data, secdata);
+		error = security_sb_eat_lsm_opts(data, &sec_opts);
 		if (error)
-			goto out_free_secdata;
+			return ERR_PTR(error);
 	}
 
 	root = type->mount(type, flags, name, data);
···
 	smp_wmb();
 	sb->s_flags |= SB_BORN;
 
-	error = security_sb_kern_mount(sb, flags, secdata);
+	error = security_sb_set_mnt_opts(sb, sec_opts, 0, NULL);
 	if (error)
 		goto out_sb;
+
+	if (!(flags & (MS_KERNMOUNT|MS_SUBMOUNT))) {
+		error = security_sb_kern_mount(sb);
+		if (error)
+			goto out_sb;
+	}
 
 	/*
 	 * filesystems should never set s_maxbytes larger than MAX_LFS_FILESIZE
···
 		"negative value (%lld)\n", type->name, sb->s_maxbytes);
 
 	up_write(&sb->s_umount);
-	free_secdata(secdata);
+	security_free_mnt_opts(&sec_opts);
 	return root;
 out_sb:
 	dput(root);
 	deactivate_locked_super(sb);
 out_free_secdata:
-	free_secdata(secdata);
-out:
+	security_free_mnt_opts(&sec_opts);
 	return ERR_PTR(error);
 }
 

include/linux/lsm_hooks.h

···
 
 	int (*sb_alloc_security)(struct super_block *sb);
 	void (*sb_free_security)(struct super_block *sb);
-	int (*sb_copy_data)(char *orig, char *copy);
-	int (*sb_remount)(struct super_block *sb, void *data);
-	int (*sb_kern_mount)(struct super_block *sb, int flags, void *data);
+	void (*sb_free_mnt_opts)(void *mnt_opts);
+	int (*sb_eat_lsm_opts)(char *orig, void **mnt_opts);
+	int (*sb_remount)(struct super_block *sb, void *mnt_opts);
+	int (*sb_kern_mount)(struct super_block *sb);
 	int (*sb_show_options)(struct seq_file *m, struct super_block *sb);
 	int (*sb_statfs)(struct dentry *dentry);
 	int (*sb_mount)(const char *dev_name, const struct path *path,
···
 	int (*sb_umount)(struct vfsmount *mnt, int flags);
 	int (*sb_pivotroot)(const struct path *old_path, const struct path *new_path);
 	int (*sb_set_mnt_opts)(struct super_block *sb,
-				struct security_mnt_opts *opts,
+				void *mnt_opts,
 				unsigned long kern_flags,
 				unsigned long *set_kern_flags);
 	int (*sb_clone_mnt_opts)(const struct super_block *oldsb,
 					struct super_block *newsb,
 					unsigned long kern_flags,
 					unsigned long *set_kern_flags);
-	int (*sb_parse_opts_str)(char *options, struct security_mnt_opts *opts);
+	int (*sb_add_mnt_opt)(const char *option, const char *val, int len,
+			      void **mnt_opts);
 	int (*dentry_init_security)(struct dentry *dentry, int mode,
 					const struct qstr *name, void **ctx,
 					u32 *ctxlen);
···
 	struct hlist_head bprm_committed_creds;
 	struct hlist_head sb_alloc_security;
 	struct hlist_head sb_free_security;
-	struct hlist_head sb_copy_data;
+	struct hlist_head sb_free_mnt_opts;
+	struct hlist_head sb_eat_lsm_opts;
 	struct hlist_head sb_remount;
 	struct hlist_head sb_kern_mount;
 	struct hlist_head sb_show_options;
···
 	struct hlist_head sb_pivotroot;
 	struct hlist_head sb_set_mnt_opts;
 	struct hlist_head sb_clone_mnt_opts;
-	struct hlist_head sb_parse_opts_str;
+	struct hlist_head sb_add_mnt_opt;
 	struct hlist_head dentry_init_security;
 	struct hlist_head dentry_create_files_as;
 #ifdef CONFIG_SECURITY_PATH

include/linux/mount.h

···
 extern void mntput(struct vfsmount *mnt);
 extern struct vfsmount *mntget(struct vfsmount *mnt);
 extern struct vfsmount *mnt_clone_internal(const struct path *path);
-extern int __mnt_is_readonly(struct vfsmount *mnt);
+extern bool __mnt_is_readonly(struct vfsmount *mnt);
 extern bool mnt_may_suid(struct vfsmount *mnt);
 
 struct path;

include/linux/security.h

···
 
 #ifdef CONFIG_SECURITY
 
-struct security_mnt_opts {
-	char **mnt_opts;
-	int *mnt_opts_flags;
-	int num_mnt_opts;
-};
-
 int call_lsm_notifier(enum lsm_event event, void *data);
 int register_lsm_notifier(struct notifier_block *nb);
 int unregister_lsm_notifier(struct notifier_block *nb);
-
-static inline void security_init_mnt_opts(struct security_mnt_opts *opts)
-{
-	opts->mnt_opts = NULL;
-	opts->mnt_opts_flags = NULL;
-	opts->num_mnt_opts = 0;
-}
-
-static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
-{
-	int i;
-	if (opts->mnt_opts)
-		for (i = 0; i < opts->num_mnt_opts; i++)
-			kfree(opts->mnt_opts[i]);
-	kfree(opts->mnt_opts);
-	opts->mnt_opts = NULL;
-	kfree(opts->mnt_opts_flags);
-	opts->mnt_opts_flags = NULL;
-	opts->num_mnt_opts = 0;
-}
 
 /* prototypes */
 extern int security_init(void);
···
 void security_bprm_committed_creds(struct linux_binprm *bprm);
 int security_sb_alloc(struct super_block *sb);
 void security_sb_free(struct super_block *sb);
-int security_sb_copy_data(char *orig, char *copy);
-int security_sb_remount(struct super_block *sb, void *data);
-int security_sb_kern_mount(struct super_block *sb, int flags, void *data);
+void security_free_mnt_opts(void **mnt_opts);
+int security_sb_eat_lsm_opts(char *options, void **mnt_opts);
+int security_sb_remount(struct super_block *sb, void *mnt_opts);
+int security_sb_kern_mount(struct super_block *sb);
 int security_sb_show_options(struct seq_file *m, struct super_block *sb);
 int security_sb_statfs(struct dentry *dentry);
 int security_sb_mount(const char *dev_name, const struct path *path,
···
 int security_sb_umount(struct vfsmount *mnt, int flags);
 int security_sb_pivotroot(const struct path *old_path, const struct path *new_path);
 int security_sb_set_mnt_opts(struct super_block *sb,
-				struct security_mnt_opts *opts,
+				void *mnt_opts,
 				unsigned long kern_flags,
 				unsigned long *set_kern_flags);
 int security_sb_clone_mnt_opts(const struct super_block *oldsb,
 				struct super_block *newsb,
 				unsigned long kern_flags,
 				unsigned long *set_kern_flags);
-int security_sb_parse_opts_str(char *options, struct security_mnt_opts *opts);
+int security_add_mnt_opt(const char *option, const char *val,
+				int len, void **mnt_opts);
 int security_dentry_init_security(struct dentry *dentry, int mode,
 					const struct qstr *name, void **ctx,
 					u32 *ctxlen);
···
 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
 int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
 #else /* CONFIG_SECURITY */
-struct security_mnt_opts {
-};
 
 static inline int call_lsm_notifier(enum lsm_event event, void *data)
 {
···
 	return 0;
 }
 
-static inline void security_init_mnt_opts(struct security_mnt_opts *opts)
-{
-}
-
-static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
+static inline void security_free_mnt_opts(void **mnt_opts)
 {
 }
 
···
 static inline void security_sb_free(struct super_block *sb)
 { }
 
-static inline int security_sb_copy_data(char *orig, char *copy)
+static inline int security_sb_eat_lsm_opts(char *options,
+					   void **mnt_opts)
 {
 	return 0;
 }
 
-static inline int security_sb_remount(struct super_block *sb, void *data)
+static inline int security_sb_remount(struct super_block *sb,
+				      void *mnt_opts)
 {
 	return 0;
 }
 
-static inline int security_sb_kern_mount(struct super_block *sb, int flags, void *data)
+static inline int security_sb_kern_mount(struct super_block *sb)
 {
 	return 0;
 }
···
 }
 
 static inline int security_sb_set_mnt_opts(struct super_block *sb,
-					   struct security_mnt_opts *opts,
+					   void *mnt_opts,
 					   unsigned long kern_flags,
 					   unsigned long *set_kern_flags)
 {
···
 	return 0;
 }
 
-static inline int security_sb_parse_opts_str(char *options, struct security_mnt_opts *opts)
+static inline int security_add_mnt_opt(const char *option, const char *val,
+					int len, void **mnt_opts)
 {
 	return 0;
 }
···
 { }
 #endif /* CONFIG_SECURITY */
 #endif /* CONFIG_BPF_SYSCALL */
-
-#ifdef CONFIG_SECURITY
-
-static inline char *alloc_secdata(void)
-{
-	return (char *)get_zeroed_page(GFP_KERNEL);
-}
-
-static inline void free_secdata(void *secdata)
-{
-	free_page((unsigned long)secdata);
-}
-
-#else
-
-static inline char *alloc_secdata(void)
-{
-        return (char *)1;
-}
-
-static inline void free_secdata(void *secdata)
-{ }
-#endif /* CONFIG_SECURITY */
 
 #endif /* ! __LINUX_SECURITY_H */
 

include/uapi/linux/fs.h

···
 #include <linux/ioctl.h>
 #include <linux/types.h>
 
+/* Use of MS_* flags within the kernel is restricted to core mount(2) code. */
+#if !defined(__KERNEL__)
+#include <linux/mount.h>
+#endif
+
 /*
  * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
  * the file limit at runtime and only root can increase the per-process
···
 
 
 #define NR_FILE  8192	/* this can well be larger on a larger system */
-
-
-/*
- * These are the fs-independent mount-flags: up to 32 flags are supported
- */
-#define MS_RDONLY	 1	/* Mount read-only */
-#define MS_NOSUID	 2	/* Ignore suid and sgid bits */
-#define MS_NODEV	 4	/* Disallow access to device special files */
-#define MS_NOEXEC	 8	/* Disallow program execution */
-#define MS_SYNCHRONOUS	16	/* Writes are synced at once */
-#define MS_REMOUNT	32	/* Alter flags of a mounted FS */
-#define MS_MANDLOCK	64	/* Allow mandatory locks on an FS */
-#define MS_DIRSYNC	128	/* Directory modifications are synchronous */
-#define MS_NOATIME	1024	/* Do not update access times. */
-#define MS_NODIRATIME	2048	/* Do not update directory access times */
-#define MS_BIND		4096
-#define MS_MOVE		8192
-#define MS_REC		16384
-#define MS_VERBOSE	32768	/* War is peace. Verbosity is silence.
-				   MS_VERBOSE is deprecated. */
-#define MS_SILENT	32768
-#define MS_POSIXACL	(1<<16)	/* VFS does not apply the umask */
-#define MS_UNBINDABLE	(1<<17)	/* change to unbindable */
-#define MS_PRIVATE	(1<<18)	/* change to private */
-#define MS_SLAVE	(1<<19)	/* change to slave */
-#define MS_SHARED	(1<<20)	/* change to shared */
-#define MS_RELATIME	(1<<21)	/* Update atime relative to mtime/ctime. */
-#define MS_KERNMOUNT	(1<<22) /* this is a kern_mount call */
-#define MS_I_VERSION	(1<<23) /* Update inode I_version field */
-#define MS_STRICTATIME	(1<<24) /* Always perform atime updates */
-#define MS_LAZYTIME	(1<<25) /* Update the on-disk [acm]times lazily */
-
-/* These sb flags are internal to the kernel */
-#define MS_SUBMOUNT     (1<<26)
-#define MS_NOREMOTELOCK	(1<<27)
-#define MS_NOSEC	(1<<28)
-#define MS_BORN		(1<<29)
-#define MS_ACTIVE	(1<<30)
-#define MS_NOUSER	(1<<31)
-
-/*
- * Superblock flags that can be altered by MS_REMOUNT
- */
-#define MS_RMT_MASK	(MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION|\
-			 MS_LAZYTIME)
-
-/*
- * Old magic mount flag and mask
- */
-#define MS_MGC_VAL 0xC0ED0000
-#define MS_MGC_MSK 0xffff0000
 
 /*
  * Structure for FS_IOC_FSGETXATTR[A] and FS_IOC_FSSETXATTR.

include/uapi/linux/mount.h

···
+#ifndef _UAPI_LINUX_MOUNT_H
+#define _UAPI_LINUX_MOUNT_H
+
+/*
+ * These are the fs-independent mount-flags: up to 32 flags are supported
+ *
+ * Usage of these is restricted within the kernel to core mount(2) code and
+ * callers of sys_mount() only.  Filesystems should be using the SB_*
+ * equivalent instead.
+ */
+#define MS_RDONLY	 1	/* Mount read-only */
+#define MS_NOSUID	 2	/* Ignore suid and sgid bits */
+#define MS_NODEV	 4	/* Disallow access to device special files */
+#define MS_NOEXEC	 8	/* Disallow program execution */
+#define MS_SYNCHRONOUS	16	/* Writes are synced at once */
+#define MS_REMOUNT	32	/* Alter flags of a mounted FS */
+#define MS_MANDLOCK	64	/* Allow mandatory locks on an FS */
+#define MS_DIRSYNC	128	/* Directory modifications are synchronous */
+#define MS_NOATIME	1024	/* Do not update access times. */
+#define MS_NODIRATIME	2048	/* Do not update directory access times */
+#define MS_BIND		4096
+#define MS_MOVE		8192
+#define MS_REC		16384
+#define MS_VERBOSE	32768	/* War is peace. Verbosity is silence.
+				   MS_VERBOSE is deprecated. */
+#define MS_SILENT	32768
+#define MS_POSIXACL	(1<<16)	/* VFS does not apply the umask */
+#define MS_UNBINDABLE	(1<<17)	/* change to unbindable */
+#define MS_PRIVATE	(1<<18)	/* change to private */
+#define MS_SLAVE	(1<<19)	/* change to slave */
+#define MS_SHARED	(1<<20)	/* change to shared */
+#define MS_RELATIME	(1<<21)	/* Update atime relative to mtime/ctime. */
+#define MS_KERNMOUNT	(1<<22) /* this is a kern_mount call */
+#define MS_I_VERSION	(1<<23) /* Update inode I_version field */
+#define MS_STRICTATIME	(1<<24) /* Always perform atime updates */
+#define MS_LAZYTIME	(1<<25) /* Update the on-disk [acm]times lazily */
+
+/* These sb flags are internal to the kernel */
+#define MS_SUBMOUNT     (1<<26)
+#define MS_NOREMOTELOCK	(1<<27)
+#define MS_NOSEC	(1<<28)
+#define MS_BORN		(1<<29)
+#define MS_ACTIVE	(1<<30)
+#define MS_NOUSER	(1<<31)
+
+/*
+ * Superblock flags that can be altered by MS_REMOUNT
+ */
+#define MS_RMT_MASK	(MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION|\
+			 MS_LAZYTIME)
+
+/*
+ * Old magic mount flag and mask
+ */
+#define MS_MGC_VAL 0xC0ED0000
+#define MS_MGC_MSK 0xffff0000
+
+#endif /* _UAPI_LINUX_MOUNT_H */

init/do_mounts.c

···
 #include <linux/nfs_fs.h>
 #include <linux/nfs_fs_sb.h>
 #include <linux/nfs_mount.h>
+#include <uapi/linux/mount.h>
 
 #include "do_mounts.h"
 

init/do_mounts_initrd.c

···
 #include <linux/sched.h>
 #include <linux/freezer.h>
 #include <linux/kmod.h>
+#include <uapi/linux/mount.h>
 
 #include "do_mounts.h"
 

security/apparmor/lsm.c

···
 #include <linux/netfilter_ipv4.h>
 #include <linux/netfilter_ipv6.h>
 #include <net/sock.h>
+#include <uapi/linux/mount.h>
 
 #include "include/apparmor.h"
 #include "include/apparmorfs.h"

security/apparmor/mount.c

···
 #include <linux/fs.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
+#include <uapi/linux/mount.h>
 
 #include "include/apparmor.h"
 #include "include/audit.h"

security/security.c

···
 	call_void_hook(sb_free_security, sb);
 }
 
-int security_sb_copy_data(char *orig, char *copy)
+void security_free_mnt_opts(void **mnt_opts)
 {
-	return call_int_hook(sb_copy_data, 0, orig, copy);
+	if (!*mnt_opts)
+		return;
+	call_void_hook(sb_free_mnt_opts, *mnt_opts);
+	*mnt_opts = NULL;
 }
-EXPORT_SYMBOL(security_sb_copy_data);
+EXPORT_SYMBOL(security_free_mnt_opts);
 
-int security_sb_remount(struct super_block *sb, void *data)
+int security_sb_eat_lsm_opts(char *options, void **mnt_opts)
 {
-	return call_int_hook(sb_remount, 0, sb, data);
+	return call_int_hook(sb_eat_lsm_opts, 0, options, mnt_opts);
 }
+EXPORT_SYMBOL(security_sb_eat_lsm_opts);
 
-int security_sb_kern_mount(struct super_block *sb, int flags, void *data)
+int security_sb_remount(struct super_block *sb,
+			void *mnt_opts)
 {
-	return call_int_hook(sb_kern_mount, 0, sb, flags, data);
+	return call_int_hook(sb_remount, 0, sb, mnt_opts);
+}
+EXPORT_SYMBOL(security_sb_remount);
+
+int security_sb_kern_mount(struct super_block *sb)
+{
+	return call_int_hook(sb_kern_mount, 0, sb);
 }
 
 int security_sb_show_options(struct seq_file *m, struct super_block *sb)
···
 }
 
 int security_sb_set_mnt_opts(struct super_block *sb,
-				struct security_mnt_opts *opts,
+				void *mnt_opts,
 				unsigned long kern_flags,
 				unsigned long *set_kern_flags)
 {
 	return call_int_hook(sb_set_mnt_opts,
-				opts->num_mnt_opts ? -EOPNOTSUPP : 0, sb,
-				opts, kern_flags, set_kern_flags);
+				mnt_opts ? -EOPNOTSUPP : 0, sb,
+				mnt_opts, kern_flags, set_kern_flags);
 }
 EXPORT_SYMBOL(security_sb_set_mnt_opts);
 
···
 }
 EXPORT_SYMBOL(security_sb_clone_mnt_opts);
 
-int security_sb_parse_opts_str(char *options, struct security_mnt_opts *opts)
+int security_add_mnt_opt(const char *option, const char *val, int len,
+			 void **mnt_opts)
 {
-	return call_int_hook(sb_parse_opts_str, 0, options, opts);
+	return call_int_hook(sb_add_mnt_opt, -EINVAL,
+					option, val, len, mnt_opts);
 }
-EXPORT_SYMBOL(security_sb_parse_opts_str);
+EXPORT_SYMBOL(security_add_mnt_opt);
 
 int security_inode_alloc(struct inode *inode)
 {

security/selinux/hooks.c

···
 #include <linux/msg.h>
 #include <linux/shm.h>
 #include <linux/bpf.h>
+#include <uapi/linux/mount.h>
 
 #include "avc.h"
 #include "objsec.h"
···
 	kfree(sbsec);
 }
 
+struct selinux_mnt_opts {
+	const char *fscontext, *context, *rootcontext, *defcontext;
+};
+
+static void selinux_free_mnt_opts(void *mnt_opts)
+{
+	struct selinux_mnt_opts *opts = mnt_opts;
+	kfree(opts->fscontext);
+	kfree(opts->context);
+	kfree(opts->rootcontext);
+	kfree(opts->defcontext);
+	kfree(opts);
+}
+
 static inline int inode_doinit(struct inode *inode)
 {
 	return inode_doinit_with_dentry(inode, NULL);
···
 	Opt_fscontext = 2,
 	Opt_defcontext = 3,
 	Opt_rootcontext = 4,
-	Opt_labelsupport = 5,
-	Opt_nextmntopt = 6,
+	Opt_seclabel = 5,
 };
 
-#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)
-
-static const match_table_t tokens = {
-	{Opt_context, CONTEXT_STR "%s"},
-	{Opt_fscontext, FSCONTEXT_STR "%s"},
-	{Opt_defcontext, DEFCONTEXT_STR "%s"},
-	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
-	{Opt_labelsupport, LABELSUPP_STR},
-	{Opt_error, NULL},
+#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
+static struct {
+	const char *name;
+	int len;
+	int opt;
+	bool has_arg;
+} tokens[] = {
+	A(context, true),
+	A(fscontext, true),
+	A(defcontext, true),
+	A(rootcontext, true),
+	A(seclabel, false),
 };
+#undef A
+
+static int match_opt_prefix(char *s, int l, char **arg)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
+		size_t len = tokens[i].len;
+		if (len > l || memcmp(s, tokens[i].name, len))
+			continue;
+		if (tokens[i].has_arg) {
+			if (len == l || s[len] != '=')
+				continue;
+			*arg = s + len + 1;
+		} else if (len != l)
+			continue;
+		return tokens[i].opt;
+	}
+	return Opt_error;
+}
 
 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 
···
 	   during get_sb by a pseudo filesystem that directly
 	   populates itself. */
 	spin_lock(&sbsec->isec_lock);
-next_inode:
-	if (!list_empty(&sbsec->isec_head)) {
+	while (!list_empty(&sbsec->isec_head)) {
 		struct inode_security_struct *isec =
-				list_entry(sbsec->isec_head.next,
+				list_first_entry(&sbsec->isec_head,
 					   struct inode_security_struct, list);
 		struct inode *inode = isec->inode;
 		list_del_init(&isec->list);
···
 			iput(inode);
 		}
 		spin_lock(&sbsec->isec_lock);
-		goto next_inode;
 	}
 	spin_unlock(&sbsec->isec_lock);
 out:
-	return rc;
-}
-
-/*
- * This function should allow an FS to ask what it's mount security
- * options were so it can use those later for submounts, displaying
- * mount options, or whatever.
- */
-static int selinux_get_mnt_opts(const struct super_block *sb,
-				struct security_mnt_opts *opts)
-{
-	int rc = 0, i;
-	struct superblock_security_struct *sbsec = sb->s_security;
-	char *context = NULL;
-	u32 len;
-	char tmp;
-
-	security_init_mnt_opts(opts);
-
-	if (!(sbsec->flags & SE_SBINITIALIZED))
-		return -EINVAL;
-
-	if (!selinux_state.initialized)
-		return -EINVAL;
-
-	/* make sure we always check enough bits to cover the mask */
-	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
-
-	tmp = sbsec->flags & SE_MNTMASK;
-	/* count the number of mount options for this sb */
-	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
-		if (tmp & 0x01)
-			opts->num_mnt_opts++;
-		tmp >>= 1;
-	}
-	/* Check if the Label support flag is set */
-	if (sbsec->flags & SBLABEL_MNT)
-		opts->num_mnt_opts++;
-
-	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
-	if (!opts->mnt_opts) {
-		rc = -ENOMEM;
-		goto out_free;
-	}
-
-	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
-	if (!opts->mnt_opts_flags) {
-		rc = -ENOMEM;
-		goto out_free;
-	}
-
-	i = 0;
-	if (sbsec->flags & FSCONTEXT_MNT) {
-		rc = security_sid_to_context(&selinux_state, sbsec->sid,
-					     &context, &len);
-		if (rc)
-			goto out_free;
-		opts->mnt_opts[i] = context;
-		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
-	}
-	if (sbsec->flags & CONTEXT_MNT) {
-		rc = security_sid_to_context(&selinux_state,
-					     sbsec->mntpoint_sid,
-					     &context, &len);
-		if (rc)
-			goto out_free;
-		opts->mnt_opts[i] = context;
-		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
-	}
-	if (sbsec->flags & DEFCONTEXT_MNT) {
-		rc = security_sid_to_context(&selinux_state, sbsec->def_sid,
-					     &context, &len);
-		if (rc)
-			goto out_free;
-		opts->mnt_opts[i] = context;
-		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
-	}
-	if (sbsec->flags & ROOTCONTEXT_MNT) {
-		struct dentry *root = sbsec->sb->s_root;
-		struct inode_security_struct *isec = backing_inode_security(root);
-
-		rc = security_sid_to_context(&selinux_state, isec->sid,
-					     &context, &len);
-		if (rc)
-			goto out_free;
-		opts->mnt_opts[i] = context;
-		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
-	}
-	if (sbsec->flags & SBLABEL_MNT) {
-		opts->mnt_opts[i] = NULL;
-		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
-	}
-
-	BUG_ON(i != opts->num_mnt_opts);
-
-	return 0;
-
-out_free:
-	security_free_mnt_opts(opts);
 	return rc;
 }
 
···
 	return 0;
 }
 
+static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
+{
+	int rc = security_context_str_to_sid(&selinux_state, s,
+					     sid, GFP_KERNEL);
+	if (rc)
+		pr_warn("SELinux: security_context_str_to_sid"
+		       "(%s) failed for (dev %s, type %s) errno=%d\n",
+		       s, sb->s_id, sb->s_type->name, rc);
+	return rc;
+}
+
 /*
  * Allow filesystems with binary mount data to explicitly set mount point
  * labeling information.
  */
 static int selinux_set_mnt_opts(struct super_block *sb,
-				struct security_mnt_opts *opts,
+				void *mnt_opts,
 				unsigned long kern_flags,
 				unsigned long *set_kern_flags)
 {
 	const struct cred *cred = current_cred();
-	int rc = 0, i;
 	struct superblock_security_struct *sbsec = sb->s_security;
-	const char *name = sb->s_type->name;
 	struct dentry *root = sbsec->sb->s_root;
+	struct selinux_mnt_opts *opts = mnt_opts;
 	struct inode_security_struct *root_isec;
 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 	u32 defcontext_sid = 0;
-	char **mount_options = opts->mnt_opts;
-	int *flags = opts->mnt_opts_flags;
-	int num_opts = opts->num_mnt_opts;
+	int rc = 0;
 
 	mutex_lock(&sbsec->lock);
 
 	if (!selinux_state.initialized) {
-		if (!num_opts) {
+		if (!opts) {
 			/* Defer initialization until selinux_complete_init,
 			   after the initial policy is loaded and the security
 			   server is ready to handle calls. */
···
 	 * will be used for both mounts)
 	 */
 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
-	    && (num_opts == 0))
+	    && !opts)
 		goto out;
 
 	root_isec = backing_inode_security_novalidate(root);
···
 	 * also check if someone is trying to mount the same sb more
 	 * than once with different security options.
 	 */
-	for (i = 0; i < num_opts; i++) {
-		u32 sid;
-
-		if (flags[i] == SBLABEL_MNT)
-			continue;
-		rc = security_context_str_to_sid(&selinux_state,
-						 mount_options[i], &sid,
-						 GFP_KERNEL);
-		if (rc) {
-			pr_warn("SELinux: security_context_str_to_sid"
-			       "(%s) failed for (dev %s, type %s) errno=%d\n",
-			       mount_options[i], sb->s_id, name, rc);
-			goto out;
-		}
-		switch (flags[i]) {
-		case FSCONTEXT_MNT:
-			fscontext_sid = sid;
-
+	if (opts) {
+		if (opts->fscontext) {
+			rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
+			if (rc)
+				goto out;
 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 					fscontext_sid))
 				goto out_double_mount;
-
 			sbsec->flags |= FSCONTEXT_MNT;
-			break;
-		case CONTEXT_MNT:
-			context_sid = sid;
-
+		}
+		if (opts->context) {
+			rc = parse_sid(sb, opts->context, &context_sid);
+			if (rc)
+				goto out;
 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 					context_sid))
 				goto out_double_mount;
-
 			sbsec->flags |= CONTEXT_MNT;
-			break;
-		case ROOTCONTEXT_MNT:
-			rootcontext_sid = sid;
-
+		}
+		if (opts->rootcontext) {
+			rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
+			if (rc)
+				goto out;
 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 					rootcontext_sid))
 				goto out_double_mount;
-
 			sbsec->flags |= ROOTCONTEXT_MNT;
-
-			break;
-		case DEFCONTEXT_MNT:
-			defcontext_sid = sid;
-
+		}
+		if (opts->defcontext) {
+			rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
+			if (rc)
+				goto out;
 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 					defcontext_sid))
 				goto out_double_mount;
-
 			sbsec->flags |= DEFCONTEXT_MNT;
-
-			break;
-		default:
-			rc = -EINVAL;
-			goto out;
 		}
 	}
 
 	if (sbsec->flags & SE_SBINITIALIZED) {
 		/* previously mounted with options, but not on this attempt? */
-		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
+		if ((sbsec->flags & SE_MNTMASK) && !opts)
 			goto out_double_mount;
 		rc = 0;
 		goto out;
···
 out_double_mount:
 	rc = -EINVAL;
 	pr_warn("SELinux: mount invalid.  Same superblock, different "
-	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
+	       "security settings for (dev %s, type %s)\n", sb->s_id,
+	       sb->s_type->name);
 	goto out;
 }
 
···
 	return rc;
 }
 
-static int selinux_parse_opts_str(char *options,
-				  struct security_mnt_opts *opts)
+static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 {
-	char *p;
-	char *context = NULL, *defcontext = NULL;
-	char *fscontext = NULL, *rootcontext = NULL;
-	int rc, num_mnt_opts = 0;
+	struct selinux_mnt_opts *opts = *mnt_opts;
 
-	opts->num_mnt_opts = 0;
+	if (token == Opt_seclabel)	/* eaten and completely ignored */
+		return 0;
 
-	/* Standard string-based options. */
-	while ((p = strsep(&options, "|")) != NULL) {
-		int token;
-		substring_t args[MAX_OPT_ARGS];
+	if (!opts) {
+		opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
+		if (!opts)
+			return -ENOMEM;
+		*mnt_opts = opts;
+	}
+	if (!s)
+		return -ENOMEM;
+	switch (token) {
+	case Opt_context:
+		if (opts->context || opts->defcontext)
+			goto Einval;
+		opts->context = s;
+		break;
+	case Opt_fscontext:
+		if (opts->fscontext)
+			goto Einval;
+		opts->fscontext = s;
+		break;
+	case Opt_rootcontext:
+		if (opts->rootcontext)
+			goto Einval;
+		opts->rootcontext = s;
+		break;
+	case Opt_defcontext:
+		if (opts->context || opts->defcontext)
+			goto Einval;
+		opts->defcontext = s;
+		break;
+	}
+	return 0;
+Einval:
+	pr_warn(SEL_MOUNT_FAIL_MSG);
+	return -EINVAL;
+}
 
-		if (!*p)
-			continue;
+static int selinux_add_mnt_opt(const char *option, const char *val, int len,
+			       void **mnt_opts)
+{
+	int token = Opt_error;
+	int rc, i;
 
-		token = match_token(p, tokens, args);
-
-		switch (token) {
-		case Opt_context:
-			if (context || defcontext) {
-				rc = -EINVAL;
-				pr_warn(SEL_MOUNT_FAIL_MSG);
-				goto out_err;
-			}
-			context = match_strdup(&args[0]);
-			if (!context) {
-				rc = -ENOMEM;
-				goto out_err;
-			}
+	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
+		if (strcmp(option, tokens[i].name) == 0) {
+			token = tokens[i].opt;
 			break;
-
-		case Opt_fscontext:
-			if (fscontext) {
-				rc = -EINVAL;
-				pr_warn(SEL_MOUNT_FAIL_MSG);
-				goto out_err;
-			}
-			fscontext = match_strdup(&args[0]);
-			if (!fscontext) {
-				rc = -ENOMEM;
-				goto out_err;
-			}
-			break;
-
-		case Opt_rootcontext:
-			if (rootcontext) {
-				rc = -EINVAL;
-				pr_warn(SEL_MOUNT_FAIL_MSG);
-				goto out_err;
-			}
-			rootcontext = match_strdup(&args[0]);
-			if (!rootcontext) {
-				rc = -ENOMEM;
-				goto out_err;
-			}
-			break;
-
-		case Opt_defcontext:
-			if (context || defcontext) {
-				rc = -EINVAL;
-				pr_warn(SEL_MOUNT_FAIL_MSG);
-				goto out_err;
-			}
-			defcontext = match_strdup(&args[0]);
-			if (!defcontext) {
-				rc = -ENOMEM;
-				goto out_err;
-			}
-			break;
-		case Opt_labelsupport:
-			break;
-		default:
-			rc = -EINVAL;
-			pr_warn("SELinux:  unknown mount option\n");
-			goto out_err;
-
 		}
 	}
 
-	rc = -ENOMEM;
-	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
-	if (!opts->mnt_opts)
-		goto out_err;
+	if (token == Opt_error)
+		return -EINVAL;
 
-	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
-				       GFP_KERNEL);
-	if (!opts->mnt_opts_flags)
-		goto out_err;
+	if (token != Opt_seclabel)
+		val = kmemdup_nul(val, len, GFP_KERNEL);
+	rc = selinux_add_opt(token, val, mnt_opts);
+	if (unlikely(rc)) {
+		kfree(val);
+		if (*mnt_opts) {
+			selinux_free_mnt_opts(*mnt_opts);
+			*mnt_opts = NULL;
+		}
+	}
+	return rc;
+}
 
-	if (fscontext) {
-		opts->mnt_opts[num_mnt_opts] = fscontext;
-		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
-	}
-	if (context) {
-		opts->mnt_opts[num_mnt_opts] = context;
-		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
-	}
-	if (rootcontext) {
-		opts->mnt_opts[num_mnt_opts] = rootcontext;
-		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
-	}
-	if (defcontext) {
-		opts->mnt_opts[num_mnt_opts] = defcontext;
-		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
-	}
+static int show_sid(struct seq_file *m, u32 sid)
+{
+	char *context = NULL;
+	u32 len;
+	int rc;
 
-	opts->num_mnt_opts = num_mnt_opts;
-	return 0;
+	rc = security_sid_to_context(&selinux_state, sid,
+					     &context, &len);
+	if (!rc) {
+		bool has_comma = context && strchr(context, ',');
 
-out_err:
-	security_free_mnt_opts(opts);
+		if (has_comma)
+			seq_putc(m, '\"');
+		seq_escape(m, context, "\"\n\\");
+		if (has_comma)
+			seq_putc(m, '\"');
+	}
 	kfree(context);
-	kfree(defcontext);
-	kfree(fscontext);
-	kfree(rootcontext);
 	return rc;
-}
-/*
- * string mount options parsing and call set the sbsec
- */
-static int superblock_doinit(struct super_block *sb, void *data)
-{
-	int rc = 0;
-	char *options = data;
-	struct security_mnt_opts opts;
-
-	security_init_mnt_opts(&opts);
-
-	if (!data)
-		goto out;
-
-	BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
-
-	rc = selinux_parse_opts_str(options, &opts);
-	if (rc)
-		goto out_err;
-
-out:
-	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
-
-out_err:
-	security_free_mnt_opts(&opts);
-	return rc;
-}
-
-static void selinux_write_opts(struct seq_file *m,
-			       struct security_mnt_opts *opts)
-{
-	int i;
-	char *prefix;
-
-	for (i = 0; i < opts->num_mnt_opts; i++) {
-		char *has_comma;
-
-		if (opts->mnt_opts[i])
-			has_comma = strchr(opts->mnt_opts[i], ',');
-		else
-			has_comma = NULL;
-
-		switch (opts->mnt_opts_flags[i]) {
-		case CONTEXT_MNT:
-			prefix = CONTEXT_STR;
-			break;
-		case FSCONTEXT_MNT:
-			prefix = FSCONTEXT_STR;
-			break;
-		case ROOTCONTEXT_MNT:
-			prefix = ROOTCONTEXT_STR;
-			break;
-		case DEFCONTEXT_MNT:
-			prefix = DEFCONTEXT_STR;
-			break;
-		case SBLABEL_MNT:
-			seq_putc(m, ',');
-			seq_puts(m, LABELSUPP_STR);
-			continue;
-		default:
-			BUG();
-			return;
-		};
-		/* we need a comma before each option */
-		seq_putc(m, ',');
-		seq_puts(m, prefix);
-		if (has_comma)
-			seq_putc(m, '\"');
-		seq_escape(m, opts->mnt_opts[i], "\"\n\\");
-		if (has_comma)
-			seq_putc(m, '\"');
-	}
 }
 
 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
 {
-	struct security_mnt_opts opts;
+	struct superblock_security_struct *sbsec = sb->s_security;
 	int rc;
 
-	rc = selinux_get_mnt_opts(sb, &opts);
-	if (rc) {
-		/* before policy load we may get EINVAL, don't show anything */
-		if (rc == -EINVAL)
-			rc = 0;
-		return rc;
+	if (!(sbsec->flags & SE_SBINITIALIZED))
+		return 0;
+
+	if (!selinux_state.initialized)
+		return 0;
+
+	if (sbsec->flags & FSCONTEXT_MNT) {
+		seq_putc(m, ',');
+		seq_puts(m, FSCONTEXT_STR);
+		rc = show_sid(m, sbsec->sid);
+		if (rc)
+			return rc;
 	}
-
-	selinux_write_opts(m, &opts);
-
-	security_free_mnt_opts(&opts);
-
-	return rc;
+	if (sbsec->flags & CONTEXT_MNT) {
+		seq_putc(m, ',');
+		seq_puts(m, CONTEXT_STR);
+		rc = show_sid(m, sbsec->mntpoint_sid);
+		if (rc)
+			return rc;
+	}
+	if (sbsec->flags & DEFCONTEXT_MNT) {
+		seq_putc(m, ',');
+		seq_puts(m, DEFCONTEXT_STR);
+		rc = show_sid(m, sbsec->def_sid);
+		if (rc)
+			return rc;
+	}
+	if (sbsec->flags & ROOTCONTEXT_MNT) {
+		struct dentry *root = sbsec->sb->s_root;
+		struct inode_security_struct *isec = backing_inode_security(root);
+		seq_putc(m, ',');
+		seq_puts(m, ROOTCONTEXT_STR);
+		rc = show_sid(m, isec->sid);
+		if (rc)
+			return rc;
+	}
+	if (sbsec->flags & SBLABEL_MNT) {
+		seq_putc(m, ',');
+		seq_puts(m, LABELSUPP_STR);
+	}
+	return 0;
 }
 
 static inline u16 inode_mode_to_security_class(umode_t mode)
···
 	superblock_free_security(sb);
 }
 
-static inline int match_prefix(char *prefix, int plen, char *option, int olen)
+static inline int opt_len(const char *s)
 {
-	if (plen > olen)
-		return 0;
+	bool open_quote = false;
+	int len;
+	char c;
 
-	return !memcmp(prefix, option, plen);
-}
-
-static inline int selinux_option(char *option, int len)
-{
-	return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
-		match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
-		match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
-		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
-		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
-}
-
-static inline void take_option(char **to, char *from, int *first, int len)
-{
-	if (!*first) {
-		**to = ',';
-		*to += 1;
-	} else
-		*first = 0;
-	memcpy(*to, from, len);
-	*to += len;
-}
-
-static inline void take_selinux_option(char **to, char *from, int *first,
-				       int len)
-{
-	int current_size = 0;
-
-	if (!*first) {
-		**to = '|';
-		*to += 1;
-	} else
-		*first = 0;
-
-	while (current_size < len) {
-		if (*from != '"') {
-			**to = *from;
-			*to += 1;
-		}
-		from += 1;
-		current_size += 1;
-	}
-}
-
-static int selinux_sb_copy_data(char *orig, char *copy)
-{
-	int fnosec, fsec, rc = 0;
-	char *in_save, *in_curr, *in_end;
-	char *sec_curr, *nosec_save, *nosec;
-	int open_quote = 0;
-
-	in_curr = orig;
-	sec_curr = copy;
-
-	nosec = (char *)get_zeroed_page(GFP_KERNEL);
-	if (!nosec) {
-		rc = -ENOMEM;
-		goto out;
-	}
-
-	nosec_save = nosec;
-	fnosec = fsec = 1;
-	in_save = in_end = orig;
-
-	do {
-		if (*in_end == '"')
+	for (len = 0; (c = s[len]) != '\0'; len++) {
+		if (c == '"')
 			open_quote = !open_quote;
-		if ((*in_end == ',' && open_quote == 0) ||
-				*in_end == '\0') {
-			int len = in_end - in_curr;
-
-			if (selinux_option(in_curr, len))
-				take_selinux_option(&sec_curr, in_curr, &fsec, len);
-			else
-				take_option(&nosec, in_curr, &fnosec, len);
-
-			in_curr = in_end + 1;
-		}
-	} while (*in_end++);
-
-	strcpy(in_save, nosec_save);
-	free_page((unsigned long)nosec_save);
-out:
-	return rc;
+		if (c == ',' && !open_quote)
+			break;
+	}
+	return len;
 }
 
-static int selinux_sb_remount(struct super_block *sb, void *data)
+static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
 {
-	int rc, i, *flags;
-	struct security_mnt_opts opts;
-	char *secdata, **mount_options;
+	char *from = options;
+	char *to = options;
+	bool first = true;
+
+	while (1) {
+		int len = opt_len(from);
+		int token, rc;
+		char *arg = NULL;
+
+		token = match_opt_prefix(from, len, &arg);
+
+		if (token != Opt_error) {
+			char *p, *q;
+
+			/* strip quotes */
+			if (arg) {
+				for (p = q = arg; p < from + len; p++) {
+					char c = *p;
+					if (c != '"')
+						*q++ = c;
+				}
+				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
+			}
+			rc = selinux_add_opt(token, arg, mnt_opts);
+			if (unlikely(rc)) {
+				kfree(arg);
+				if (*mnt_opts) {
+					selinux_free_mnt_opts(*mnt_opts);
+					*mnt_opts = NULL;
+				}
+				return rc;
+			}
+		} else {
+			if (!first) {	// copy with preceding comma
+				from--;
+				len++;
+			}
+			if (to != from)
+				memmove(to, from, len);
+			to += len;
+			first = false;
+		}
+		if (!from[len])
+			break;
+		from += len + 1;
+	}
+	*to = '\0';
+	return 0;
+}
+
+static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
+{
+	struct selinux_mnt_opts *opts = mnt_opts;
 	struct superblock_security_struct *sbsec = sb->s_security;
+	u32 sid;
+	int rc;
 
 	if (!(sbsec->flags & SE_SBINITIALIZED))
 		return 0;
 
-	if (!data)
+	if (!opts)
 		return 0;
 
-	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
-		return 0;
-
-	security_init_mnt_opts(&opts);
-	secdata = alloc_secdata();
-	if (!secdata)
-		return -ENOMEM;
-	rc = selinux_sb_copy_data(data, secdata);
-	if (rc)
-		goto out_free_secdata;
-
-	rc = selinux_parse_opts_str(secdata, &opts);
-	if (rc)
-		goto out_free_secdata;
-
-	mount_options = opts.mnt_opts;
-	flags = opts.mnt_opts_flags;
-
-	for (i = 0; i < opts.num_mnt_opts; i++) {
-		u32 sid;
-
-		if (flags[i] == SBLABEL_MNT)
-			continue;
-		rc = security_context_str_to_sid(&selinux_state,
-						 mount_options[i], &sid,
-						 GFP_KERNEL);
-		if (rc) {
-			pr_warn("SELinux: security_context_str_to_sid"
-			       "(%s) failed for (dev %s, type %s) errno=%d\n",
-			       mount_options[i], sb->s_id, sb->s_type->name, rc);
-			goto out_free_opts;
-		}
-		rc = -EINVAL;
-		switch (flags[i]) {
-		case FSCONTEXT_MNT:
-			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
-				goto out_bad_option;
-			break;
-		case CONTEXT_MNT:
-			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
-				goto out_bad_option;
-			break;
-		case ROOTCONTEXT_MNT: {
-			struct inode_security_struct *root_isec;
-			root_isec = backing_inode_security(sb->s_root);
-
-			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
-				goto out_bad_option;
-			break;
-		}
-		case DEFCONTEXT_MNT:
-			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
-				goto out_bad_option;
-			break;
-		default:
-			goto out_free_opts;
-		}
+	if (opts->fscontext) {
+		rc = parse_sid(sb, opts->fscontext, &sid);
+		if (rc)
+			return rc;
+		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
+			goto out_bad_option;
 	}
+	if (opts->context) {
+		rc = parse_sid(sb, opts->context, &sid);
+		if (rc)
+			return rc;
+		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
+			goto out_bad_option;
+	}
+	if (opts->rootcontext) {
+		struct inode_security_struct *root_isec;
+		root_isec = backing_inode_security(sb->s_root);
+		rc = parse_sid(sb, opts->rootcontext, &sid);
+		if (rc)
+			return rc;
+		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
+			goto out_bad_option;
+	}
+	if (opts->defcontext) {
+		rc = parse_sid(sb, opts->defcontext, &sid);
+		if (rc)
+			return rc;
+		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
+			goto out_bad_option;
+	}
+	return 0;
 
-	rc = 0;
-out_free_opts:
-	security_free_mnt_opts(&opts);
-out_free_secdata:
-	free_secdata(secdata);
-	return rc;
 out_bad_option:
 	pr_warn("SELinux: unable to change security options "
 	       "during remount (dev %s, type=%s)\n", sb->s_id,
 	       sb->s_type->name);
-	goto out_free_opts;
+	return -EINVAL;
 }
 
-static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
+static int selinux_sb_kern_mount(struct super_block *sb)
 {
 	const struct cred *cred = current_cred();
 	struct common_audit_data ad;
-	int rc;
-
-	rc = superblock_doinit(sb, data);
-	if (rc)
-		return rc;
-
-	/* Allow all mounts performed by the kernel */
-	if (flags & (MS_KERNMOUNT | MS_SUBMOUNT))
-		return 0;
 
 	ad.type = LSM_AUDIT_DATA_DENTRY;
 	ad.u.dentry = sb->s_root;
···
 
 	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
 	LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
-	LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
+	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
+	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
 	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
 	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
 	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
···
 	LSM_HOOK_INIT(sb_umount, selinux_umount),
 	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
-	LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
+	LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
 
 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
···
 
 static void delayed_superblock_init(struct super_block *sb, void *unused)
 {
-	superblock_doinit(sb, NULL);
+	selinux_set_mnt_opts(sb, NULL, 0, NULL);
 }
 
 void selinux_complete_init(void)

security/smack/smack_lsm.c

···
 static struct kmem_cache *smack_inode_cache;
 int smack_enabled;
 
-static const match_table_t smk_mount_tokens = {
-	{Opt_fsdefault, SMK_FSDEFAULT "%s"},
-	{Opt_fsfloor, SMK_FSFLOOR "%s"},
-	{Opt_fshat, SMK_FSHAT "%s"},
-	{Opt_fsroot, SMK_FSROOT "%s"},
-	{Opt_fstransmute, SMK_FSTRANS "%s"},
-	{Opt_error, NULL},
+#define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
+static struct {
+	const char *name;
+	int len;
+	int opt;
+} smk_mount_opts[] = {
+	A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute)
 };
+#undef A
+
+static int match_opt_prefix(char *s, int l, char **arg)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(smk_mount_opts); i++) {
+		size_t len = smk_mount_opts[i].len;
+		if (len > l || memcmp(s, smk_mount_opts[i].name, len))
+			continue;
+		if (len == l || s[len] != '=')
+			continue;
+		*arg = s + len + 1;
+		return smk_mount_opts[i].opt;
+	}
+	return Opt_error;
+}
 
 #ifdef CONFIG_SECURITY_SMACK_BRINGUP
 static char *smk_bu_mess[] = {
···
 	sb->s_security = NULL;
 }
 
-/**
- * smack_sb_copy_data - copy mount options data for processing
- * @orig: where to start
- * @smackopts: mount options string
- *
- * Returns 0 on success or -ENOMEM on error.
- *
- * Copy the Smack specific mount options out of the mount
- * options list.
- */
-static int smack_sb_copy_data(char *orig, char *smackopts)
+struct smack_mnt_opts {
+	const char *fsdefault, *fsfloor, *fshat, *fsroot, *fstransmute;
+};
+
+static void smack_free_mnt_opts(void *mnt_opts)
 {
-	char *cp, *commap, *otheropts, *dp;
-
-	otheropts = (char *)get_zeroed_page(GFP_KERNEL);
-	if (otheropts == NULL)
-		return -ENOMEM;
-
-	for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
-		if (strstr(cp, SMK_FSDEFAULT) == cp)
-			dp = smackopts;
-		else if (strstr(cp, SMK_FSFLOOR) == cp)
-			dp = smackopts;
-		else if (strstr(cp, SMK_FSHAT) == cp)
-			dp = smackopts;
-		else if (strstr(cp, SMK_FSROOT) == cp)
-			dp = smackopts;
-		else if (strstr(cp, SMK_FSTRANS) == cp)
-			dp = smackopts;
-		else
-			dp = otheropts;
-
-		commap = strchr(cp, ',');
-		if (commap != NULL)
-			*commap = '\0';
-
-		if (*dp != '\0')
-			strcat(dp, ",");
-		strcat(dp, cp);
-	}
-
-	strcpy(orig, otheropts);
-	free_page((unsigned long)otheropts);
-
-	return 0;
+	struct smack_mnt_opts *opts = mnt_opts;
+	kfree(opts->fsdefault);
+	kfree(opts->fsfloor);
+	kfree(opts->fshat);
+	kfree(opts->fsroot);
+	kfree(opts->fstransmute);
+	kfree(opts);
 }
 
-/**
- * smack_parse_opts_str - parse Smack specific mount options
- * @options: mount options string
- * @opts: where to store converted mount opts
- *
- * Returns 0 on success or -ENOMEM on error.
- *
- * converts Smack specific mount options to generic security option format
- */
-static int smack_parse_opts_str(char *options,
-		struct security_mnt_opts *opts)
+static int smack_add_opt(int token, const char *s, void **mnt_opts)
 {
-	char *p;
-	char *fsdefault = NULL;
-	char *fsfloor = NULL;
-	char *fshat = NULL;
-	char *fsroot = NULL;
-	char *fstransmute = NULL;
-	int rc = -ENOMEM;
-	int num_mnt_opts = 0;
-	int token;
+	struct smack_mnt_opts *opts = *mnt_opts;
 
-	opts->num_mnt_opts = 0;
-
-	if (!options)
-		return 0;
-
-	while ((p = strsep(&options, ",")) != NULL) {
-		substring_t args[MAX_OPT_ARGS];
-
-		if (!*p)
-			continue;
-
-		token = match_token(p, smk_mount_tokens, args);
-
-		switch (token) {
-		case Opt_fsdefault:
-			if (fsdefault)
-				goto out_opt_err;
-			fsdefault = match_strdup(&args[0]);
-			if (!fsdefault)
-				goto out_err;
-			break;
-		case Opt_fsfloor:
-			if (fsfloor)
-				goto out_opt_err;
-			fsfloor = match_strdup(&args[0]);
-			if (!fsfloor)
-				goto out_err;
-			break;
-		case Opt_fshat:
-			if (fshat)
-				goto out_opt_err;
-			fshat = match_strdup(&args[0]);
-			if (!fshat)
-				goto out_err;
-			break;
-		case Opt_fsroot:
-			if (fsroot)
-				goto out_opt_err;
-			fsroot = match_strdup(&args[0]);
-			if (!fsroot)
-				goto out_err;
-			break;
-		case Opt_fstransmute:
-			if (fstransmute)
-				goto out_opt_err;
-			fstransmute = match_strdup(&args[0]);
-			if (!fstransmute)
-				goto out_err;
-			break;
-		default:
-			rc = -EINVAL;
-			pr_warn("Smack:  unknown mount option\n");
-			goto out_err;
-		}
+	if (!opts) {
+		opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
+		if (!opts)
+			return -ENOMEM;
+		*mnt_opts = opts;
 	}
+	if (!s)
+		return -ENOMEM;
 
-	opts->mnt_opts = kcalloc(NUM_SMK_MNT_OPTS, sizeof(char *), GFP_KERNEL);
-	if (!opts->mnt_opts)
-		goto out_err;
-
-	opts->mnt_opts_flags = kcalloc(NUM_SMK_MNT_OPTS, sizeof(int),
-			GFP_KERNEL);
-	if (!opts->mnt_opts_flags)
-		goto out_err;
-
-	if (fsdefault) {
-		opts->mnt_opts[num_mnt_opts] = fsdefault;
-		opts->mnt_opts_flags[num_mnt_opts++] = FSDEFAULT_MNT;
+	switch (token) {
+	case Opt_fsdefault:
+		if (opts->fsdefault)
+			goto out_opt_err;
+		opts->fsdefault = s;
+		break;
+	case Opt_fsfloor:
+		if (opts->fsfloor)
+			goto out_opt_err;
+		opts->fsfloor = s;
+		break;
+	case Opt_fshat:
+		if (opts->fshat)
+			goto out_opt_err;
+		opts->fshat = s;
+		break;
+	case Opt_fsroot:
+		if (opts->fsroot)
+			goto out_opt_err;
+		opts->fsroot = s;
+		break;
+	case Opt_fstransmute:
+		if (opts->fstransmute)
+			goto out_opt_err;
+		opts->fstransmute = s;
+		break;
 	}
-	if (fsfloor) {
-		opts->mnt_opts[num_mnt_opts] = fsfloor;
-		opts->mnt_opts_flags[num_mnt_opts++] = FSFLOOR_MNT;
-	}
-	if (fshat) {
-		opts->mnt_opts[num_mnt_opts] = fshat;
-		opts->mnt_opts_flags[num_mnt_opts++] = FSHAT_MNT;
-	}
-	if (fsroot) {
-		opts->mnt_opts[num_mnt_opts] = fsroot;
-		opts->mnt_opts_flags[num_mnt_opts++] = FSROOT_MNT;
-	}
-	if (fstransmute) {
-		opts->mnt_opts[num_mnt_opts] = fstransmute;
-		opts->mnt_opts_flags[num_mnt_opts++] = FSTRANS_MNT;
-	}
-
-	opts->num_mnt_opts = num_mnt_opts;
 	return 0;
 
 out_opt_err:
-	rc = -EINVAL;
 	pr_warn("Smack: duplicate mount options\n");
+	return -EINVAL;
+}
 
-out_err:
-	kfree(fsdefault);
-	kfree(fsfloor);
-	kfree(fshat);
-	kfree(fsroot);
-	kfree(fstransmute);
-	return rc;
+static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
+{
+	char *from = options, *to = options;
+	bool first = true;
+
+	while (1) {
+		char *next = strchr(from, ',');
+		int token, len, rc;
+		char *arg = NULL;
+
+		if (next)
+			len = next - from;
+		else
+			len = strlen(from);
+
+		token = match_opt_prefix(from, len, &arg);
+		if (token != Opt_error) {
+			arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL);
+			rc = smack_add_opt(token, arg, mnt_opts);
+			if (unlikely(rc)) {
+				kfree(arg);
+				if (*mnt_opts)
+					smack_free_mnt_opts(*mnt_opts);
+				*mnt_opts = NULL;
+				return rc;
+			}
+		} else {
+			if (!first) {	// copy with preceding comma
+				from--;
+				len++;
+			}
+			if (to != from)
+				memmove(to, from, len);
+			to += len;
+			first = false;
+		}
+		if (!from[len])
+			break;
+		from += len + 1;
+	}
+	*to = '\0';
+	return 0;
 }
 
 /**
···
  * labels.
  */
 static int smack_set_mnt_opts(struct super_block *sb,
-		struct security_mnt_opts *opts,
+		void *mnt_opts,
 		unsigned long kern_flags,
 		unsigned long *set_kern_flags)
 {
···
 	struct superblock_smack *sp = sb->s_security;
 	struct inode_smack *isp;
 	struct smack_known *skp;
-	int i;
-	int num_opts = opts->num_mnt_opts;
-	int transmute = 0;
+	struct smack_mnt_opts *opts = mnt_opts;
+	bool transmute = false;
 
 	if (sp->smk_flags & SMK_SB_INITIALIZED)
 		return 0;
···
 		/*
 		 * Unprivileged mounts don't get to specify Smack values.
 		 */
-		if (num_opts)
+		if (opts)
 			return -EPERM;
 		/*
 		 * Unprivileged mounts get root and default from the caller.
···
 		if (sb->s_user_ns != &init_user_ns &&
 		    sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
 		    sb->s_magic != RAMFS_MAGIC) {
-			transmute = 1;
+			transmute = true;
 			sp->smk_flags |= SMK_SB_UNTRUSTED;
 		}
 	}
 
 	sp->smk_flags |= SMK_SB_INITIALIZED;
 
-	for (i = 0; i < num_opts; i++) {
-		switch (opts->mnt_opts_flags[i]) {
-		case FSDEFAULT_MNT:
-			skp = smk_import_entry(opts->mnt_opts[i], 0);
+	if (opts) {
+		if (opts->fsdefault) {
+			skp = smk_import_entry(opts->fsdefault, 0);
 			if (IS_ERR(skp))
 				return PTR_ERR(skp);
 			sp->smk_default = skp;
-			break;
-		case FSFLOOR_MNT:
-			skp = smk_import_entry(opts->mnt_opts[i], 0);
+		}
+		if (opts->fsfloor) {
+			skp = smk_import_entry(opts->fsfloor, 0);
 			if (IS_ERR(skp))
 				return PTR_ERR(skp);
 			sp->smk_floor = skp;
-			break;
-		case FSHAT_MNT:
-			skp = smk_import_entry(opts->mnt_opts[i], 0);
+		}
+		if (opts->fshat) {
+			skp = smk_import_entry(opts->fshat, 0);
 			if (IS_ERR(skp))
 				return PTR_ERR(skp);
 			sp->smk_hat = skp;
-			break;
-		case FSROOT_MNT:
-			skp = smk_import_entry(opts->mnt_opts[i], 0);
+		}
+		if (opts->fsroot) {
+			skp = smk_import_entry(opts->fsroot, 0);
 			if (IS_ERR(skp))
 				return PTR_ERR(skp);
 			sp->smk_root = skp;
-			break;
-		case FSTRANS_MNT:
-			skp = smk_import_entry(opts->mnt_opts[i], 0);
+		}
+		if (opts->fstransmute) {
+			skp = smk_import_entry(opts->fstransmute, 0);
 			if (IS_ERR(skp))
 				return PTR_ERR(skp);
 			sp->smk_root = skp;
-			transmute = 1;
-			break;
-		default:
-			break;
+			transmute = true;
 		}
 	}
 
···
 		isp->smk_flags |= SMK_INODE_TRANSMUTE;
 
 	return 0;
-}
-
-/**
- * smack_sb_kern_mount - Smack specific mount processing
- * @sb: the file system superblock
- * @flags: the mount flags
- * @data: the smack mount options
- *
- * Returns 0 on success, an error code on failure
- */
-static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
-{
-	int rc = 0;
-	char *options = data;
-	struct security_mnt_opts opts;
-
-	security_init_mnt_opts(&opts);
-
-	if (!options)
-		goto out;
-
-	rc = smack_parse_opts_str(options, &opts);
-	if (rc)
-		goto out_err;
-
-out:
-	rc = smack_set_mnt_opts(sb, &opts, 0, NULL);
-
-out_err:
-	security_free_mnt_opts(&opts);
-	return rc;
 }
 
 /**
···
 
 	LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
 	LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
-	LSM_HOOK_INIT(sb_copy_data, smack_sb_copy_data),
-	LSM_HOOK_INIT(sb_kern_mount, smack_sb_kern_mount),
+	LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
+	LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
 	LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
 	LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
-	LSM_HOOK_INIT(sb_parse_opts_str, smack_parse_opts_str),
 
 	LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
 

security/tomoyo/mount.c

···
  */
 
 #include <linux/slab.h>
+#include <uapi/linux/mount.h>
 #include "common.h"
 
 /* String table for special mount operations. */