From c08ce39b3cedc908d69e34a82f2595232c06c3b9 Mon Sep 17 00:00:00 2001
From: Daniel Rosenberg <drosen@google.com>
Date: Wed, 26 Oct 2016 16:27:45 -0700
Subject: [PATCH] vfs: Add permission2 for filesystems with per mount
 permissions

This allows filesystems to use their mount private data to
influence the permssions they return in permission2. It has
been separated into a new call to avoid disrupting current
permission users.

Change-Id: I9d416e3b8b6eca84ef3e336bd2af89ddd51df6ca
Signed-off-by: Daniel Rosenberg <drosen@google.com>
---
 fs/exec.c                          |   2 +-
 fs/namei.c                         | 177 ++++++++++++++++++++---------
 fs/notify/fanotify/fanotify_user.c |   2 +-
 fs/notify/inotify/inotify_user.c   |   2 +-
 fs/open.c                          |  16 ++-
 fs/utimes.c                        |   2 +-
 include/linux/fs.h                 |  11 ++
 include/linux/namei.h              |   1 +
 ipc/mqueue.c                       |  10 +-
 security/inode.c                   |   2 +-
 10 files changed, 159 insertions(+), 66 deletions(-)

diff --git a/fs/exec.c b/fs/exec.c
index b7a5f46181b0..b079500cb496 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1092,7 +1092,7 @@ EXPORT_SYMBOL(flush_old_exec);
 
 void would_dump(struct linux_binprm *bprm, struct file *file)
 {
-	if (inode_permission(file_inode(file), MAY_READ) < 0)
+	if (inode_permission2(file->f_path.mnt, file_inode(file), MAY_READ) < 0)
 		bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
 }
 EXPORT_SYMBOL(would_dump);
diff --git a/fs/namei.c b/fs/namei.c
index b23f15cee576..5feb2d32ea35 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -368,9 +368,11 @@ EXPORT_SYMBOL(generic_permission);
  * flag in inode->i_opflags, that says "this has not special
  * permission function, use the fast case".
  */
-static inline int do_inode_permission(struct inode *inode, int mask)
+static inline int do_inode_permission(struct vfsmount *mnt, struct inode *inode, int mask)
 {
 	if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) {
+		if (likely(mnt && inode->i_op->permission2))
+			return inode->i_op->permission2(mnt, inode, mask);
 		if (likely(inode->i_op->permission))
 			return inode->i_op->permission(inode, mask);
 
@@ -394,7 +396,7 @@ static inline int do_inode_permission(struct inode *inode, int mask)
  * This does not check for a read-only file system.  You probably want
  * inode_permission().
  */
-int __inode_permission(struct inode *inode, int mask)
+int __inode_permission2(struct vfsmount *mnt, struct inode *inode, int mask)
 {
 	int retval;
 
@@ -406,7 +408,7 @@ int __inode_permission(struct inode *inode, int mask)
 			return -EACCES;
 	}
 
-	retval = do_inode_permission(inode, mask);
+	retval = do_inode_permission(mnt, inode, mask);
 	if (retval)
 		return retval;
 
@@ -414,7 +416,14 @@ int __inode_permission(struct inode *inode, int mask)
 	if (retval)
 		return retval;
 
-	return security_inode_permission(inode, mask);
+	retval = security_inode_permission(inode, mask);
+	return retval;
+}
+EXPORT_SYMBOL(__inode_permission2);
+
+int __inode_permission(struct inode *inode, int mask)
+{
+	return __inode_permission2(NULL, inode, mask);
 }
 EXPORT_SYMBOL(__inode_permission);
 
@@ -450,14 +459,20 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
  *
  * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask.
  */
-int inode_permission(struct inode *inode, int mask)
+int inode_permission2(struct vfsmount *mnt, struct inode *inode, int mask)
 {
 	int retval;
 
 	retval = sb_permission(inode->i_sb, inode, mask);
 	if (retval)
 		return retval;
-	return __inode_permission(inode, mask);
+	return __inode_permission2(mnt, inode, mask);
+}
+EXPORT_SYMBOL(inode_permission2);
+
+int inode_permission(struct inode *inode, int mask)
+{
+	return inode_permission2(NULL, inode, mask);
 }
 EXPORT_SYMBOL(inode_permission);
 
@@ -1512,13 +1527,13 @@ static int lookup_slow(struct nameidata *nd, struct path *path)
 static inline int may_lookup(struct nameidata *nd)
 {
 	if (nd->flags & LOOKUP_RCU) {
-		int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
+		int err = inode_permission2(nd->path.mnt, nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
 		if (err != -ECHILD)
 			return err;
 		if (unlazy_walk(nd, NULL))
 			return -ECHILD;
 	}
-	return inode_permission(nd->inode, MAY_EXEC);
+	return inode_permission2(nd->path.mnt, nd->inode, MAY_EXEC);
 }
 
 static inline int handle_dots(struct nameidata *nd, int type)
@@ -1856,11 +1871,12 @@ static int path_init(int dfd, const char *name, unsigned int flags,
 	nd->depth = 0;
 	if (flags & LOOKUP_ROOT) {
 		struct dentry *root = nd->root.dentry;
+		struct vfsmount *mnt = nd->root.mnt;
 		struct inode *inode = root->d_inode;
 		if (*name) {
 			if (!d_can_lookup(root))
 				return -ENOTDIR;
-			retval = inode_permission(inode, MAY_EXEC);
+			retval = inode_permission2(mnt, inode, MAY_EXEC);
 			if (retval)
 				return retval;
 		}
@@ -2114,6 +2130,7 @@ static struct dentry *lookup_hash(struct nameidata *nd)
 /**
  * lookup_one_len - filesystem helper to lookup single pathname component
  * @name:	pathname component to lookup
+ * @mnt:	mount we are looking up on
  * @base:	base directory to lookup from
  * @len:	maximum length @len should be interpreted to
  *
@@ -2122,7 +2139,7 @@ static struct dentry *lookup_hash(struct nameidata *nd)
  * nameidata argument is passed to the filesystem methods and a filesystem
  * using this helper needs to be prepared for that.
  */
-struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)
+struct dentry *lookup_one_len2(const char *name, struct vfsmount *mnt, struct dentry *base, int len)
 {
 	struct qstr this;
 	unsigned int c;
@@ -2156,12 +2173,18 @@ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)
 			return ERR_PTR(err);
 	}
 
-	err = inode_permission(base->d_inode, MAY_EXEC);
+	err = inode_permission2(mnt, base->d_inode, MAY_EXEC);
 	if (err)
 		return ERR_PTR(err);
 
 	return __lookup_hash(&this, base, 0);
 }
+EXPORT_SYMBOL(lookup_one_len2);
+
+struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)
+{
+	return lookup_one_len2(name, NULL, base, len);
+}
 EXPORT_SYMBOL(lookup_one_len);
 
 int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
@@ -2441,7 +2464,7 @@ EXPORT_SYMBOL(__check_sticky);
  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
  *     nfs_async_unlink().
  */
-static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
+static int may_delete(struct vfsmount *mnt, struct inode *dir, struct dentry *victim, bool isdir)
 {
 	struct inode *inode = victim->d_inode;
 	int error;
@@ -2453,7 +2476,7 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
 	BUG_ON(victim->d_parent->d_inode != dir);
 	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 
-	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	error = inode_permission2(mnt, dir, MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 	if (IS_APPEND(dir))
@@ -2484,14 +2507,14 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
  *  3. We should have write and exec permissions on dir
  *  4. We can't do it if dir is immutable (done in permission())
  */
-static inline int may_create(struct inode *dir, struct dentry *child)
+static inline int may_create(struct vfsmount *mnt, struct inode *dir, struct dentry *child)
 {
 	audit_inode_child(dir, child, AUDIT_TYPE_CHILD_CREATE);
 	if (child->d_inode)
 		return -EEXIST;
 	if (IS_DEADDIR(dir))
 		return -ENOENT;
-	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	return inode_permission2(mnt, dir, MAY_WRITE | MAY_EXEC);
 }
 
 /*
@@ -2538,10 +2561,10 @@ void unlock_rename(struct dentry *p1, struct dentry *p2)
 }
 EXPORT_SYMBOL(unlock_rename);
 
-int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool want_excl)
+int vfs_create2(struct vfsmount *mnt, struct inode *dir, struct dentry *dentry,
+		umode_t mode, bool want_excl)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt, dir, dentry);
 	if (error)
 		return error;
 
@@ -2563,11 +2586,19 @@ int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 
 	return error;
 }
+EXPORT_SYMBOL(vfs_create2);
+
+int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+		bool want_excl)
+{
+	return vfs_create2(NULL, dir, dentry, mode, want_excl);
+}
 EXPORT_SYMBOL(vfs_create);
 
 static int may_open(struct path *path, int acc_mode, int flag)
 {
 	struct dentry *dentry = path->dentry;
+	struct vfsmount *mnt = path->mnt;
 	struct inode *inode = dentry->d_inode;
 	int error;
 
@@ -2596,7 +2627,7 @@ static int may_open(struct path *path, int acc_mode, int flag)
 		break;
 	}
 
-	error = inode_permission(inode, acc_mode);
+	error = inode_permission2(mnt, inode, acc_mode);
 	if (error)
 		return error;
 
@@ -2631,7 +2662,7 @@ static int handle_truncate(struct file *filp)
 	if (!error)
 		error = security_path_truncate(path);
 	if (!error) {
-		error = do_truncate(path->dentry, 0,
+		error = do_truncate2(path->mnt, path->dentry, 0,
 				    ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
 				    filp);
 	}
@@ -2652,7 +2683,7 @@ static int may_o_create(struct path *dir, struct dentry *dentry, umode_t mode)
 	if (error)
 		return error;
 
-	error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
+	error = inode_permission2(dir->mnt, dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 
@@ -2850,6 +2881,7 @@ static int lookup_open(struct nameidata *nd, struct path *path,
 			bool got_write, int *opened)
 {
 	struct dentry *dir = nd->path.dentry;
+	struct vfsmount *mnt = nd->path.mnt;
 	struct inode *dir_inode = dir->d_inode;
 	struct dentry *dentry;
 	int error;
@@ -2897,7 +2929,7 @@ static int lookup_open(struct nameidata *nd, struct path *path,
 		error = security_path_mknod(&nd->path, dentry, mode, 0);
 		if (error)
 			goto out_dput;
-		error = vfs_create(dir->d_inode, dentry, mode,
+		error = vfs_create2(mnt, dir->d_inode, dentry, mode,
 				   nd->flags & LOOKUP_EXCL);
 		if (error)
 			goto out_dput;
@@ -3165,7 +3197,7 @@ static int do_tmpfile(int dfd, struct filename *pathname,
 	if (unlikely(error))
 		goto out;
 	/* we want directory to be writable */
-	error = inode_permission(nd->inode, MAY_WRITE | MAY_EXEC);
+	error = inode_permission2(nd->path.mnt, nd->inode, MAY_WRITE | MAY_EXEC);
 	if (error)
 		goto out2;
 	dentry = nd->path.dentry;
@@ -3413,9 +3445,9 @@ struct dentry *user_path_create(int dfd, const char __user *pathname,
 }
 EXPORT_SYMBOL(user_path_create);
 
-int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+int vfs_mknod2(struct vfsmount *mnt, struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt, dir, dentry);
 
 	if (error)
 		return error;
@@ -3447,6 +3479,12 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
 
 	return error;
 }
+EXPORT_SYMBOL(vfs_mknod2);
+
+int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+{
+	return vfs_mknod2(NULL, dir, dentry, mode, dev);
+}
 EXPORT_SYMBOL(vfs_mknod);
 
 static int may_mknod(umode_t mode)
@@ -3489,10 +3527,10 @@ retry:
 		goto out;
 	switch (mode & S_IFMT) {
 		case 0: case S_IFREG:
-			error = vfs_create(path.dentry->d_inode,dentry,mode,true);
+			error = vfs_create2(path.mnt, path.dentry->d_inode,dentry,mode,true);
 			break;
 		case S_IFCHR: case S_IFBLK:
-			error = vfs_mknod(path.dentry->d_inode,dentry,mode,
+			error = vfs_mknod2(path.mnt, path.dentry->d_inode,dentry,mode,
 					new_decode_dev(dev));
 			break;
 		case S_IFIFO: case S_IFSOCK:
@@ -3513,9 +3551,9 @@ SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, d
 	return sys_mknodat(AT_FDCWD, filename, mode, dev);
 }
 
-int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+int vfs_mkdir2(struct vfsmount *mnt, struct inode *dir, struct dentry *dentry, umode_t mode)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt, dir, dentry);
 	unsigned max_links = dir->i_sb->s_max_links;
 
 	if (error)
@@ -3537,6 +3575,12 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 		fsnotify_mkdir(dir, dentry);
 	return error;
 }
+EXPORT_SYMBOL(vfs_mkdir2);
+
+int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+	return vfs_mkdir2(NULL, dir, dentry, mode);
+}
 EXPORT_SYMBOL(vfs_mkdir);
 
 SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
@@ -3555,7 +3599,7 @@ retry:
 		mode &= ~current_umask();
 	error = security_path_mkdir(&path, dentry, mode);
 	if (!error)
-		error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
+		error = vfs_mkdir2(path.mnt, path.dentry->d_inode, dentry, mode);
 	done_path_create(&path, dentry);
 	if (retry_estale(error, lookup_flags)) {
 		lookup_flags |= LOOKUP_REVAL;
@@ -3594,9 +3638,9 @@ void dentry_unhash(struct dentry *dentry)
 }
 EXPORT_SYMBOL(dentry_unhash);
 
-int vfs_rmdir(struct inode *dir, struct dentry *dentry)
+int vfs_rmdir2(struct vfsmount *mnt, struct inode *dir, struct dentry *dentry)
 {
-	int error = may_delete(dir, dentry, 1);
+	int error = may_delete(mnt, dir, dentry, 1);
 
 	if (error)
 		return error;
@@ -3631,6 +3675,10 @@ out:
 		d_delete(dentry);
 	return error;
 }
+int vfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	return vfs_rmdir2(NULL, dir, dentry);
+}
 EXPORT_SYMBOL(vfs_rmdir);
 
 static long do_rmdir(int dfd, const char __user *pathname)
@@ -3674,7 +3722,7 @@ retry:
 	error = security_path_rmdir(&nd.path, dentry);
 	if (error)
 		goto exit3;
-	error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
+	error = vfs_rmdir2(nd.path.mnt, nd.path.dentry->d_inode, dentry);
 exit3:
 	dput(dentry);
 exit2:
@@ -3713,10 +3761,10 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
  * be appropriate for callers that expect the underlying filesystem not
  * to be NFS exported.
  */
-int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode)
+int vfs_unlink2(struct vfsmount *mnt, struct inode *dir, struct dentry *dentry, struct inode **delegated_inode)
 {
 	struct inode *target = dentry->d_inode;
-	int error = may_delete(dir, dentry, 0);
+	int error = may_delete(mnt, dir, dentry, 0);
 
 	if (error)
 		return error;
@@ -3751,6 +3799,12 @@ out:
 
 	return error;
 }
+EXPORT_SYMBOL(vfs_unlink2);
+
+int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode)
+{
+	return vfs_unlink2(NULL, dir, dentry, delegated_inode);
+}
 EXPORT_SYMBOL(vfs_unlink);
 
 /*
@@ -3796,7 +3850,7 @@ retry_deleg:
 		error = security_path_unlink(&nd.path, dentry);
 		if (error)
 			goto exit2;
-		error = vfs_unlink(nd.path.dentry->d_inode, dentry, &delegated_inode);
+		error = vfs_unlink2(nd.path.mnt, nd.path.dentry->d_inode, dentry, &delegated_inode);
 exit2:
 		dput(dentry);
 	}
@@ -3846,9 +3900,9 @@ SYSCALL_DEFINE1(unlink, const char __user *, pathname)
 	return do_unlinkat(AT_FDCWD, pathname);
 }
 
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
+int vfs_symlink2(struct vfsmount *mnt, struct inode *dir, struct dentry *dentry, const char *oldname)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt, dir, dentry);
 
 	if (error)
 		return error;
@@ -3865,6 +3919,12 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
 		fsnotify_create(dir, dentry);
 	return error;
 }
+EXPORT_SYMBOL(vfs_symlink2);
+
+int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
+{
+	return vfs_symlink2(NULL, dir, dentry, oldname);
+}
 EXPORT_SYMBOL(vfs_symlink);
 
 SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
@@ -3887,7 +3947,7 @@ retry:
 
 	error = security_path_symlink(&path, dentry, from->name);
 	if (!error)
-		error = vfs_symlink(path.dentry->d_inode, dentry, from->name);
+		error = vfs_symlink2(path.mnt, path.dentry->d_inode, dentry, from->name);
 	done_path_create(&path, dentry);
 	if (retry_estale(error, lookup_flags)) {
 		lookup_flags |= LOOKUP_REVAL;
@@ -3922,7 +3982,7 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn
  * be appropriate for callers that expect the underlying filesystem not
  * to be NFS exported.
  */
-int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode)
+int vfs_link2(struct vfsmount *mnt, struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode)
 {
 	struct inode *inode = old_dentry->d_inode;
 	unsigned max_links = dir->i_sb->s_max_links;
@@ -3931,7 +3991,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
 	if (!inode)
 		return -ENOENT;
 
-	error = may_create(dir, new_dentry);
+	error = may_create(mnt, dir, new_dentry);
 	if (error)
 		return error;
 
@@ -3974,6 +4034,12 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
 		fsnotify_link(dir, inode, new_dentry);
 	return error;
 }
+EXPORT_SYMBOL(vfs_link2);
+
+int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode)
+{
+	return vfs_link2(NULL, old_dentry, dir, new_dentry, delegated_inode);
+}
 EXPORT_SYMBOL(vfs_link);
 
 /*
@@ -4029,7 +4095,7 @@ retry:
 	error = security_path_link(old_path.dentry, &new_path, new_dentry);
 	if (error)
 		goto out_dput;
-	error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode);
+	error = vfs_link2(old_path.mnt, old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode);
 out_dput:
 	done_path_create(&new_path, new_dentry);
 	if (delegated_inode) {
@@ -4104,7 +4170,8 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
  *	   ->i_mutex on parents, which works but leads to some truly excessive
  *	   locking].
  */
-int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+int vfs_rename2(struct vfsmount *mnt,
+	       struct inode *old_dir, struct dentry *old_dentry,
 	       struct inode *new_dir, struct dentry *new_dentry,
 	       struct inode **delegated_inode, unsigned int flags)
 {
@@ -4119,19 +4186,19 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (source == target)
 		return 0;
 
-	error = may_delete(old_dir, old_dentry, is_dir);
+	error = may_delete(mnt, old_dir, old_dentry, is_dir);
 	if (error)
 		return error;
 
 	if (!target) {
-		error = may_create(new_dir, new_dentry);
+		error = may_create(mnt, new_dir, new_dentry);
 	} else {
 		new_is_dir = d_is_dir(new_dentry);
 
 		if (!(flags & RENAME_EXCHANGE))
-			error = may_delete(new_dir, new_dentry, is_dir);
+			error = may_delete(mnt, new_dir, new_dentry, is_dir);
 		else
-			error = may_delete(new_dir, new_dentry, new_is_dir);
+			error = may_delete(mnt, new_dir, new_dentry, new_is_dir);
 	}
 	if (error)
 		return error;
@@ -4148,12 +4215,12 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	 */
 	if (new_dir != old_dir) {
 		if (is_dir) {
-			error = inode_permission(source, MAY_WRITE);
+			error = inode_permission2(mnt, source, MAY_WRITE);
 			if (error)
 				return error;
 		}
 		if ((flags & RENAME_EXCHANGE) && new_is_dir) {
-			error = inode_permission(target, MAY_WRITE);
+			error = inode_permission2(mnt, target, MAY_WRITE);
 			if (error)
 				return error;
 		}
@@ -4236,6 +4303,14 @@ out:
 
 	return error;
 }
+EXPORT_SYMBOL(vfs_rename2);
+
+int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+	       struct inode *new_dir, struct dentry *new_dentry,
+	       struct inode **delegated_inode, unsigned int flags)
+{
+	return vfs_rename2(NULL, old_dir, old_dentry, new_dir, new_dentry, delegated_inode, flags);
+}
 EXPORT_SYMBOL(vfs_rename);
 
 SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
@@ -4350,7 +4425,7 @@ retry_deleg:
 				     &newnd.path, new_dentry, flags);
 	if (error)
 		goto exit5;
-	error = vfs_rename(old_dir->d_inode, old_dentry,
+	error = vfs_rename2(oldnd.path.mnt, old_dir->d_inode, old_dentry,
 			   new_dir->d_inode, new_dentry,
 			   &delegated_inode, flags);
 exit5:
@@ -4395,7 +4470,7 @@ SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newna
 
 int vfs_whiteout(struct inode *dir, struct dentry *dentry)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(NULL, dir, dentry);
 	if (error)
 		return error;
 
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index c991616acca9..fcbb414721d2 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -475,7 +475,7 @@ static int fanotify_find_path(int dfd, const char __user *filename,
 	}
 
 	/* you can only watch an inode if you have read permissions on it */
-	ret = inode_permission(path->dentry->d_inode, MAY_READ);
+	ret = inode_permission2(path->mnt, path->dentry->d_inode, MAY_READ);
 	if (ret)
 		path_put(path);
 out:
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index ed833baf73db..b2ddc882dac9 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -338,7 +338,7 @@ static int inotify_find_inode(const char __user *dirname, struct path *path, uns
 	if (error)
 		return error;
 	/* you can only watch an inode if you have read permissions on it */
-	error = inode_permission(path->dentry->d_inode, MAY_READ);
+	error = inode_permission2(path->mnt, path->dentry->d_inode, MAY_READ);
 	if (error)
 		path_put(path);
 	return error;
diff --git a/fs/open.c b/fs/open.c
index d058ff1b841b..6a37a4a50dc6 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -66,9 +66,11 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 long vfs_truncate(struct path *path, loff_t length)
 {
 	struct inode *inode;
+	struct vfsmount *mnt;
 	long error;
 
 	inode = path->dentry->d_inode;
+	mnt = path->mnt;
 
 	/* For directories it's -EISDIR, for other non-regulars - -EINVAL */
 	if (S_ISDIR(inode->i_mode))
@@ -80,7 +82,7 @@ long vfs_truncate(struct path *path, loff_t length)
 	if (error)
 		goto out;
 
-	error = inode_permission(inode, MAY_WRITE);
+	error = inode_permission2(mnt, inode, MAY_WRITE);
 	if (error)
 		goto mnt_drop_write_and_out;
 
@@ -322,6 +324,7 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
 	struct cred *override_cred;
 	struct path path;
 	struct inode *inode;
+	struct vfsmount *mnt;
 	int res;
 	unsigned int lookup_flags = LOOKUP_FOLLOW;
 
@@ -352,6 +355,7 @@ retry:
 		goto out;
 
 	inode = path.dentry->d_inode;
+	mnt = path.mnt;
 
 	if ((mode & MAY_EXEC) && S_ISREG(inode->i_mode)) {
 		/*
@@ -363,7 +367,7 @@ retry:
 			goto out_path_release;
 	}
 
-	res = inode_permission(inode, mode | MAY_ACCESS);
+	res = inode_permission2(mnt, inode, mode | MAY_ACCESS);
 	/* SuS v2 requires we report a read only fs too */
 	if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
 		goto out_path_release;
@@ -407,7 +411,7 @@ retry:
 	if (error)
 		goto out;
 
-	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	error = inode_permission2(path.mnt, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
 	if (error)
 		goto dput_and_out;
 
@@ -427,6 +431,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
 {
 	struct fd f = fdget_raw(fd);
 	struct inode *inode;
+	struct vfsmount *mnt;
 	int error = -EBADF;
 
 	error = -EBADF;
@@ -434,12 +439,13 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
 		goto out;
 
 	inode = file_inode(f.file);
+	mnt = f.file->f_path.mnt;
 
 	error = -ENOTDIR;
 	if (!S_ISDIR(inode->i_mode))
 		goto out_putf;
 
-	error = inode_permission(inode, MAY_EXEC | MAY_CHDIR);
+	error = inode_permission2(mnt, inode, MAY_EXEC | MAY_CHDIR);
 	if (!error)
 		set_fs_pwd(current->fs, &f.file->f_path);
 out_putf:
@@ -458,7 +464,7 @@ retry:
 	if (error)
 		goto out;
 
-	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	error = inode_permission2(path.mnt, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
 	if (error)
 		goto dput_and_out;
 
diff --git a/fs/utimes.c b/fs/utimes.c
index aa138d64560a..c3c663dbf083 100644
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -97,7 +97,7 @@ static int utimes_common(struct path *path, struct timespec *times)
 			goto mnt_drop_write_and_out;
 
 		if (!inode_owner_or_capable(inode)) {
-			error = inode_permission(inode, MAY_WRITE);
+			error = inode_permission2(path->mnt, inode, MAY_WRITE);
 			if (error)
 				goto mnt_drop_write_and_out;
 		}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index bccaef71ee8c..089f6fd22868 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1419,13 +1419,21 @@ extern bool inode_owner_or_capable(const struct inode *inode);
  * VFS helper functions..
  */
 extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
+extern int vfs_create2(struct vfsmount *, struct inode *, struct dentry *, umode_t, bool);
 extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
+extern int vfs_mkdir2(struct vfsmount *, struct inode *, struct dentry *, umode_t);
 extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
+extern int vfs_mknod2(struct vfsmount *, struct inode *, struct dentry *, umode_t, dev_t);
 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
+extern int vfs_symlink2(struct vfsmount *, struct inode *, struct dentry *, const char *);
 extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
+extern int vfs_link2(struct vfsmount *, struct dentry *, struct inode *, struct dentry *, struct inode **);
 extern int vfs_rmdir(struct inode *, struct dentry *);
+extern int vfs_rmdir2(struct vfsmount *, struct inode *, struct dentry *);
 extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
+extern int vfs_unlink2(struct vfsmount *, struct inode *, struct dentry *, struct inode **);
 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
+extern int vfs_rename2(struct vfsmount *, struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
 extern int vfs_whiteout(struct inode *, struct dentry *);
 
 /*
@@ -1527,6 +1535,7 @@ struct inode_operations {
 	struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
 	void * (*follow_link) (struct dentry *, struct nameidata *);
 	int (*permission) (struct inode *, int);
+	int (*permission2) (struct vfsmount *, struct inode *, int);
 	struct posix_acl * (*get_acl)(struct inode *, int);
 
 	int (*readlink) (struct dentry *, char __user *,int);
@@ -2294,7 +2303,9 @@ extern sector_t bmap(struct inode *, sector_t);
 #endif
 extern int notify_change(struct dentry *, struct iattr *, struct inode **);
 extern int inode_permission(struct inode *, int);
+extern int inode_permission2(struct vfsmount *, struct inode *, int);
 extern int __inode_permission(struct inode *, int);
+extern int __inode_permission2(struct vfsmount *, struct inode *, int);
 extern int generic_permission(struct inode *, int);
 extern int __check_sticky(struct inode *dir, struct inode *inode);
 
diff --git a/include/linux/namei.h b/include/linux/namei.h
index c9ad7a100d05..f6ff630b39aa 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -75,6 +75,7 @@ extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
 		const char *, unsigned int, struct path *);
 
 extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
+extern struct dentry *lookup_one_len2(const char *, struct vfsmount *mnt, struct dentry *, int);
 
 extern int follow_down_one(struct path *);
 extern int follow_down(struct path *);
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index f65a044d66c5..3949468d5af1 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -751,7 +751,7 @@ static struct file *do_create(struct ipc_namespace *ipc_ns, struct inode *dir,
 	}
 
 	mode &= ~current_umask();
-	ret = vfs_create(dir, path->dentry, mode, true);
+	ret = vfs_create2(path->mnt, dir, path->dentry, mode, true);
 	path->dentry->d_fsdata = NULL;
 	if (ret)
 		return ERR_PTR(ret);
@@ -767,7 +767,7 @@ static struct file *do_open(struct path *path, int oflag)
 	if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY))
 		return ERR_PTR(-EINVAL);
 	acc = oflag2acc[oflag & O_ACCMODE];
-	if (inode_permission(path->dentry->d_inode, acc))
+	if (inode_permission2(path->mnt, path->dentry->d_inode, acc))
 		return ERR_PTR(-EACCES);
 	return dentry_open(path, oflag, current_cred());
 }
@@ -800,7 +800,7 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
 	ro = mnt_want_write(mnt);	/* we'll drop it in any case */
 	error = 0;
 	mutex_lock(&root->d_inode->i_mutex);
-	path.dentry = lookup_one_len(name->name, root, strlen(name->name));
+	path.dentry = lookup_one_len2(name->name, mnt, root, strlen(name->name));
 	if (IS_ERR(path.dentry)) {
 		error = PTR_ERR(path.dentry);
 		goto out_putfd;
@@ -871,7 +871,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
 	if (err)
 		goto out_name;
 	mutex_lock_nested(&mnt->mnt_root->d_inode->i_mutex, I_MUTEX_PARENT);
-	dentry = lookup_one_len(name->name, mnt->mnt_root,
+	dentry = lookup_one_len2(name->name, mnt, mnt->mnt_root,
 				strlen(name->name));
 	if (IS_ERR(dentry)) {
 		err = PTR_ERR(dentry);
@@ -883,7 +883,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
 		err = -ENOENT;
 	} else {
 		ihold(inode);
-		err = vfs_unlink(dentry->d_parent->d_inode, dentry, NULL);
+		err = vfs_unlink2(mnt, dentry->d_parent->d_inode, dentry, NULL);
 	}
 	dput(dentry);
 
diff --git a/security/inode.c b/security/inode.c
index 8e7ca62078ab..b5f9474e58d8 100644
--- a/security/inode.c
+++ b/security/inode.c
@@ -105,7 +105,7 @@ struct dentry *securityfs_create_file(const char *name, umode_t mode,
 	dir = parent->d_inode;
 
 	mutex_lock(&dir->i_mutex);
-	dentry = lookup_one_len(name, parent, strlen(name));
+	dentry = lookup_one_len2(name, mount, parent, strlen(name));
 	if (IS_ERR(dentry))
 		goto out;
 
-- 
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