Merge tag 'ovl-fixes-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs fixes from Miklos Szeredi:
 "This contains a fix for the vfs_mkdir() issue discovered by Al, as
  well as other fixes and cleanups"

* tag 'ovl-fixes-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: use inode_insert5() to hash a newly created inode
  ovl: Pass argument to ovl_get_inode() in a structure
  vfs: factor out inode_insert5()
  ovl: clean up copy-up error paths
  ovl: return EIO on internal error
  ovl: make ovl_create_real() cope with vfs_mkdir() safely
  ovl: create helper ovl_create_temp()
  ovl: return dentry from ovl_create_real()
  ovl: struct cattr cleanups
  ovl: strip debug argument from ovl_do_ helpers
  ovl: remove WARN_ON() real inode attributes mismatch
  ovl: Kconfig documentation fixes
  ovl: update documentation for unionmount-testsuite

Documentation/filesystems/overlayfs.txt

@@ -429,11 +429,12 @@ This verification may cause significant overhead in some cases.
 Testsuite
 ---------
 
-There's testsuite developed by David Howells at:
+There's a testsuite originally developed by David Howells and currently
+maintained by Amir Goldstein at:
 
-  git://git.infradead.org/users/dhowells/unionmount-testsuite.git
+  https://github.com/amir73il/unionmount-testsuite.git
 
 Run as root:
 
   # cd unionmount-testsuite
-  # ./run --ov
+  # ./run --ov --verify

fs/inode.c

@@ -1003,6 +1003,70 @@ void unlock_two_nondirectories(struct inode *inode1, struct inode *inode2)
 }
 EXPORT_SYMBOL(unlock_two_nondirectories);
 
+/**
+ * inode_insert5 - obtain an inode from a mounted file system
+ * @inode:	pre-allocated inode to use for insert to cache
+ * @hashval:	hash value (usually inode number) to get
+ * @test:	callback used for comparisons between inodes
+ * @set:	callback used to initialize a new struct inode
+ * @data:	opaque data pointer to pass to @test and @set
+ *
+ * Search for the inode specified by @hashval and @data in the inode cache,
+ * and if present it is return it with an increased reference count. This is
+ * a variant of iget5_locked() for callers that don't want to fail on memory
+ * allocation of inode.
+ *
+ * If the inode is not in cache, insert the pre-allocated inode to cache and
+ * return it locked, hashed, and with the I_NEW flag set. The file system gets
+ * to fill it in before unlocking it via unlock_new_inode().
+ *
+ * Note both @test and @set are called with the inode_hash_lock held, so can't
+ * sleep.
+ */
+struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
+			    int (*test)(struct inode *, void *),
+			    int (*set)(struct inode *, void *), void *data)
+{
+	struct hlist_head *head = inode_hashtable + hash(inode->i_sb, hashval);
+	struct inode *old;
+
+again:
+	spin_lock(&inode_hash_lock);
+	old = find_inode(inode->i_sb, head, test, data);
+	if (unlikely(old)) {
+		/*
+		 * Uhhuh, somebody else created the same inode under us.
+		 * Use the old inode instead of the preallocated one.
+		 */
+		spin_unlock(&inode_hash_lock);
+		wait_on_inode(old);
+		if (unlikely(inode_unhashed(old))) {
+			iput(old);
+			goto again;
+		}
+		return old;
+	}
+
+	if (set && unlikely(set(inode, data))) {
+		inode = NULL;
+		goto unlock;
+	}
+
+	/*
+	 * Return the locked inode with I_NEW set, the
+	 * caller is responsible for filling in the contents
+	 */
+	spin_lock(&inode->i_lock);
+	inode->i_state |= I_NEW;
+	hlist_add_head(&inode->i_hash, head);
+	spin_unlock(&inode->i_lock);
+unlock:
+	spin_unlock(&inode_hash_lock);
+
+	return inode;
+}
+EXPORT_SYMBOL(inode_insert5);
+
 /**
  * iget5_locked - obtain an inode from a mounted file system
  * @sb:		super block of file system
@@ -1027,66 +1091,18 @@ struct inode *iget5_locked(struct super_block *sb, unsigned long hashval,
 		int (*test)(struct inode *, void *),
 		int (*set)(struct inode *, void *), void *data)
 {
-	struct hlist_head *head = inode_hashtable + hash(sb, hashval);
-	struct inode *inode;
-again:
-	spin_lock(&inode_hash_lock);
-	inode = find_inode(sb, head, test, data);
-	spin_unlock(&inode_hash_lock);
+	struct inode *inode = ilookup5(sb, hashval, test, data);
 
-	if (inode) {
-		wait_on_inode(inode);
-		if (unlikely(inode_unhashed(inode))) {
-			iput(inode);
-			goto again;
-		}
-		return inode;
-	}
+	if (!inode) {
+		struct inode *new = new_inode(sb);
 
-	inode = alloc_inode(sb);
-	if (inode) {
-		struct inode *old;
-
-		spin_lock(&inode_hash_lock);
-		/* We released the lock, so.. */
-		old = find_inode(sb, head, test, data);
-		if (!old) {
-			if (set(inode, data))
-				goto set_failed;
-
-			spin_lock(&inode->i_lock);
-			inode->i_state = I_NEW;
-			hlist_add_head(&inode->i_hash, head);
-			spin_unlock(&inode->i_lock);
-			inode_sb_list_add(inode);
-			spin_unlock(&inode_hash_lock);
-
-			/* Return the locked inode with I_NEW set, the
-			 * caller is responsible for filling in the contents
-			 */
-			return inode;
-		}
-
-		/*
-		 * Uhhuh, somebody else created the same inode under
-		 * us. Use the old inode instead of the one we just
-		 * allocated.
-		 */
-		spin_unlock(&inode_hash_lock);
-		destroy_inode(inode);
-		inode = old;
-		wait_on_inode(inode);
-		if (unlikely(inode_unhashed(inode))) {
-			iput(inode);
-			goto again;
+		if (new) {
+			inode = inode_insert5(new, hashval, test, set, data);
+			if (unlikely(inode != new))
+				iput(new);
 		}
 	}
 	return inode;
-
-set_failed:
-	spin_unlock(&inode_hash_lock);
-	destroy_inode(inode);
-	return NULL;
 }
 EXPORT_SYMBOL(iget5_locked);
 
@@ -1427,43 +1443,13 @@ EXPORT_SYMBOL(insert_inode_locked);
 int insert_inode_locked4(struct inode *inode, unsigned long hashval,
 		int (*test)(struct inode *, void *), void *data)
 {
-	struct super_block *sb = inode->i_sb;
-	struct hlist_head *head = inode_hashtable + hash(sb, hashval);
+	struct inode *old = inode_insert5(inode, hashval, test, NULL, data);
 
-	while (1) {
-		struct inode *old = NULL;
-
-		spin_lock(&inode_hash_lock);
-		hlist_for_each_entry(old, head, i_hash) {
-			if (old->i_sb != sb)
-				continue;
-			if (!test(old, data))
-				continue;
-			spin_lock(&old->i_lock);
-			if (old->i_state & (I_FREEING|I_WILL_FREE)) {
-				spin_unlock(&old->i_lock);
-				continue;
-			}
-			break;
-		}
-		if (likely(!old)) {
-			spin_lock(&inode->i_lock);
-			inode->i_state |= I_NEW;
-			hlist_add_head(&inode->i_hash, head);
-			spin_unlock(&inode->i_lock);
-			spin_unlock(&inode_hash_lock);
-			return 0;
-		}
-		__iget(old);
-		spin_unlock(&old->i_lock);
-		spin_unlock(&inode_hash_lock);
-		wait_on_inode(old);
-		if (unlikely(!inode_unhashed(old))) {
-			iput(old);
-			return -EBUSY;
-		}
+	if (old != inode) {
 		iput(old);
+		return -EBUSY;
 	}
+	return 0;
 }
 EXPORT_SYMBOL(insert_inode_locked4);
 

fs/overlayfs/Kconfig

@@ -11,7 +11,7 @@ config OVERLAY_FS
 	  For more information see Documentation/filesystems/overlayfs.txt
 
 config OVERLAY_FS_REDIRECT_DIR
-	bool "Overlayfs: turn on redirect dir feature by default"
+	bool "Overlayfs: turn on redirect directory feature by default"
 	depends on OVERLAY_FS
 	help
 	  If this config option is enabled then overlay filesystems will use
@@ -46,7 +46,7 @@ config OVERLAY_FS_INDEX
 	depends on OVERLAY_FS
 	help
 	  If this config option is enabled then overlay filesystems will use
-	  the inodes index dir to map lower inodes to upper inodes by default.
+	  the index directory to map lower inodes to upper inodes by default.
 	  In this case it is still possible to turn off index globally with the
 	  "index=off" module option or on a filesystem instance basis with the
 	  "index=off" mount option.
@@ -66,7 +66,7 @@ config OVERLAY_FS_NFS_EXPORT
 	depends on OVERLAY_FS_INDEX
 	help
 	  If this config option is enabled then overlay filesystems will use
-	  the inodes index dir to decode overlay NFS file handles by default.
+	  the index directory to decode overlay NFS file handles by default.
 	  In this case, it is still possible to turn off NFS export support
 	  globally with the "nfs_export=off" module option or on a filesystem
 	  instance basis with the "nfs_export=off" mount option.

fs/overlayfs/copy_up.c

@@ -365,17 +365,14 @@ static int ovl_create_index(struct dentry *dentry, struct dentry *origin,
 	if (err)
 		return err;
 
-	temp = ovl_lookup_temp(indexdir);
+	temp = ovl_create_temp(indexdir, OVL_CATTR(S_IFDIR | 0));
+	err = PTR_ERR(temp);
 	if (IS_ERR(temp))
-		goto temp_err;
-
-	err = ovl_do_mkdir(dir, temp, S_IFDIR, true);
-	if (err)
-		goto out;
+		goto free_name;
 
 	err = ovl_set_upper_fh(upper, temp);
 	if (err)
-		goto out_cleanup;
+		goto out;
 
 	index = lookup_one_len(name.name, indexdir, name.len);
 	if (IS_ERR(index)) {
@@ -384,23 +381,13 @@ static int ovl_create_index(struct dentry *dentry, struct dentry *origin,
 		err = ovl_do_rename(dir, temp, dir, index, 0);
 		dput(index);
 	}
-
-	if (err)
-		goto out_cleanup;
-
 out:
+	if (err)
+		ovl_cleanup(dir, temp);
 	dput(temp);
+free_name:
 	kfree(name.name);
 	return err;
-
-temp_err:
-	err = PTR_ERR(temp);
-	temp = NULL;
-	goto out;
-
-out_cleanup:
-	ovl_cleanup(dir, temp);
-	goto out;
 }
 
 struct ovl_copy_up_ctx {
@@ -439,8 +426,7 @@ static int ovl_link_up(struct ovl_copy_up_ctx *c)
 			       c->dentry->d_name.len);
 	err = PTR_ERR(upper);
 	if (!IS_ERR(upper)) {
-		err = ovl_do_link(ovl_dentry_upper(c->dentry), udir, upper,
-				  true);
+		err = ovl_do_link(ovl_dentry_upper(c->dentry), udir, upper);
 		dput(upper);
 
 		if (!err) {
@@ -470,7 +456,7 @@ static int ovl_install_temp(struct ovl_copy_up_ctx *c, struct dentry *temp,
 		return PTR_ERR(upper);
 
 	if (c->tmpfile)
-		err = ovl_do_link(temp, udir, upper, true);
+		err = ovl_do_link(temp, udir, upper);
 	else
 		err = ovl_do_rename(d_inode(c->workdir), temp, udir, upper, 0);
 
@@ -481,13 +467,13 @@ static int ovl_install_temp(struct ovl_copy_up_ctx *c, struct dentry *temp,
 	return err;
 }
 
-static int ovl_get_tmpfile(struct ovl_copy_up_ctx *c, struct dentry **tempp)
+static struct dentry *ovl_get_tmpfile(struct ovl_copy_up_ctx *c)
 {
 	int err;
 	struct dentry *temp;
 	const struct cred *old_creds = NULL;
 	struct cred *new_creds = NULL;
-	struct cattr cattr = {
+	struct ovl_cattr cattr = {
 		/* Can't properly set mode on creation because of the umask */
 		.mode = c->stat.mode & S_IFMT,
 		.rdev = c->stat.rdev,
@@ -495,41 +481,24 @@ static int ovl_get_tmpfile(struct ovl_copy_up_ctx *c, struct dentry **tempp)
 	};
 
 	err = security_inode_copy_up(c->dentry, &new_creds);
+	temp = ERR_PTR(err);
 	if (err < 0)
 		goto out;
 
 	if (new_creds)
 		old_creds = override_creds(new_creds);
 
-	if (c->tmpfile) {
+	if (c->tmpfile)
 		temp = ovl_do_tmpfile(c->workdir, c->stat.mode);
-		if (IS_ERR(temp))
-			goto temp_err;
-	} else {
-		temp = ovl_lookup_temp(c->workdir);
-		if (IS_ERR(temp))
-			goto temp_err;
-
-		err = ovl_create_real(d_inode(c->workdir), temp, &cattr,
-				      NULL, true);
-		if (err) {
-			dput(temp);
-			goto out;
-		}
-	}
-	err = 0;
-	*tempp = temp;
+	else
+		temp = ovl_create_temp(c->workdir, &cattr);
 out:
 	if (new_creds) {
 		revert_creds(old_creds);
 		put_cred(new_creds);
 	}
 
-	return err;
-
-temp_err:
-	err = PTR_ERR(temp);
-	goto out;
+	return temp;
 }
 
 static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp)
@@ -579,21 +548,21 @@ static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c)
 	struct inode *udir = c->destdir->d_inode;
 	struct inode *inode;
 	struct dentry *newdentry = NULL;
-	struct dentry *temp = NULL;
+	struct dentry *temp;
 	int err;
 
-	err = ovl_get_tmpfile(c, &temp);
-	if (err)
-		goto out;
+	temp = ovl_get_tmpfile(c);
+	if (IS_ERR(temp))
+		return PTR_ERR(temp);
 
 	err = ovl_copy_up_inode(c, temp);
 	if (err)
-		goto out_cleanup;
+		goto out;
 
 	if (S_ISDIR(c->stat.mode) && c->indexed) {
 		err = ovl_create_index(c->dentry, c->lowerpath.dentry, temp);
 		if (err)
-			goto out_cleanup;
+			goto out;
 	}
 
 	if (c->tmpfile) {
@@ -604,7 +573,7 @@ static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c)
 		err = ovl_install_temp(c, temp, &newdentry);
 	}
 	if (err)
-		goto out_cleanup;
+		goto out;
 
 	inode = d_inode(c->dentry);
 	ovl_inode_update(inode, newdentry);
@@ -612,13 +581,11 @@ static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c)
 		ovl_set_flag(OVL_WHITEOUTS, inode);
 
 out:
+	if (err && !c->tmpfile)
+		ovl_cleanup(d_inode(c->workdir), temp);
 	dput(temp);
 	return err;
 
-out_cleanup:
-	if (!c->tmpfile)
-		ovl_cleanup(d_inode(c->workdir), temp);
-	goto out;
 }
 
 /*

fs/overlayfs/export.c

@@ -300,12 +300,18 @@ static struct dentry *ovl_obtain_alias(struct super_block *sb,
 	struct dentry *dentry;
 	struct inode *inode;
 	struct ovl_entry *oe;
+	struct ovl_inode_params oip = {
+		.lowerpath = lowerpath,
+		.index = index,
+		.numlower = !!lower
+	};
 
 	/* We get overlay directory dentries with ovl_lookup_real() */
 	if (d_is_dir(upper ?: lower))
 		return ERR_PTR(-EIO);
 
-	inode = ovl_get_inode(sb, dget(upper), lowerpath, index, !!lower);
+	oip.upperdentry = dget(upper);
+	inode = ovl_get_inode(sb, &oip);
 	if (IS_ERR(inode)) {
 		dput(upper);
 		return ERR_CAST(inode);

fs/overlayfs/inode.c

@@ -749,15 +749,26 @@ static bool ovl_hash_bylower(struct super_block *sb, struct dentry *upper,
 	return true;
 }
 
-struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,
-			    struct ovl_path *lowerpath, struct dentry *index,
-			    unsigned int numlower)
+static struct inode *ovl_iget5(struct super_block *sb, struct inode *newinode,
+			       struct inode *key)
 {
+	return newinode ? inode_insert5(newinode, (unsigned long) key,
+					 ovl_inode_test, ovl_inode_set, key) :
+			  iget5_locked(sb, (unsigned long) key,
+				       ovl_inode_test, ovl_inode_set, key);
+}
+
+struct inode *ovl_get_inode(struct super_block *sb,
+			    struct ovl_inode_params *oip)
+{
+	struct dentry *upperdentry = oip->upperdentry;
+	struct ovl_path *lowerpath = oip->lowerpath;
 	struct inode *realinode = upperdentry ? d_inode(upperdentry) : NULL;
 	struct inode *inode;
 	struct dentry *lowerdentry = lowerpath ? lowerpath->dentry : NULL;
-	bool bylower = ovl_hash_bylower(sb, upperdentry, lowerdentry, index);
-	int fsid = bylower ? lowerpath->layer->fsid : 0;
+	bool bylower = ovl_hash_bylower(sb, upperdentry, lowerdentry,
+					oip->index);
+	int fsid = bylower ? oip->lowerpath->layer->fsid : 0;
 	bool is_dir;
 	unsigned long ino = 0;
 
@@ -774,8 +785,7 @@ struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,
 						      upperdentry);
 		unsigned int nlink = is_dir ? 1 : realinode->i_nlink;
 
-		inode = iget5_locked(sb, (unsigned long) key,
-				     ovl_inode_test, ovl_inode_set, key);
+		inode = ovl_iget5(sb, oip->newinode, key);
 		if (!inode)
 			goto out_nomem;
 		if (!(inode->i_state & I_NEW)) {
@@ -811,12 +821,12 @@ struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,
 	if (upperdentry && ovl_is_impuredir(upperdentry))
 		ovl_set_flag(OVL_IMPURE, inode);
 
-	if (index)
+	if (oip->index)
 		ovl_set_flag(OVL_INDEX, inode);
 
 	/* Check for non-merge dir that may have whiteouts */
 	if (is_dir) {
-		if (((upperdentry && lowerdentry) || numlower > 1) ||
+		if (((upperdentry && lowerdentry) || oip->numlower > 1) ||
 		    ovl_check_origin_xattr(upperdentry ?: lowerdentry)) {
 			ovl_set_flag(OVL_WHITEOUTS, inode);
 		}

fs/overlayfs/namei.c

@@ -1004,8 +1004,14 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 		upperdentry = dget(index);
 
 	if (upperdentry || ctr) {
-		inode = ovl_get_inode(dentry->d_sb, upperdentry, stack, index,
-				      ctr);
+		struct ovl_inode_params oip = {
+			.upperdentry = upperdentry,
+			.lowerpath = stack,
+			.index = index,
+			.numlower = ctr,
+		};
+
+		inode = ovl_get_inode(dentry->d_sb, &oip);
 		err = PTR_ERR(inode);
 		if (IS_ERR(inode))
 			goto out_free_oe;

fs/overlayfs/overlayfs.h

@@ -86,6 +86,7 @@ struct ovl_fh {
 static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	int err = vfs_rmdir(dir, dentry);
+
 	pr_debug("rmdir(%pd2) = %i\n", dentry, err);
 	return err;
 }
@@ -93,56 +94,52 @@ static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
 static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
 {
 	int err = vfs_unlink(dir, dentry, NULL);
+
 	pr_debug("unlink(%pd2) = %i\n", dentry, err);
 	return err;
 }
 
 static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
-			      struct dentry *new_dentry, bool debug)
+			      struct dentry *new_dentry)
 {
 	int err = vfs_link(old_dentry, dir, new_dentry, NULL);
-	if (debug) {
-		pr_debug("link(%pd2, %pd2) = %i\n",
-			 old_dentry, new_dentry, err);
-	}
+
+	pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err);
 	return err;
 }
 
 static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
-			     umode_t mode, bool debug)
+				umode_t mode)
 {
 	int err = vfs_create(dir, dentry, mode, true);
-	if (debug)
-		pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
+
+	pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
 	return err;
 }
 
 static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
-			       umode_t mode, bool debug)
+			       umode_t mode)
 {
 	int err = vfs_mkdir(dir, dentry, mode);
-	if (debug)
-		pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
+	pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
 	return err;
 }
 
 static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
-			       umode_t mode, dev_t dev, bool debug)
+			       umode_t mode, dev_t dev)
 {
 	int err = vfs_mknod(dir, dentry, mode, dev);
-	if (debug) {
-		pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n",
-			 dentry, mode, dev, err);
-	}
+
+	pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err);
 	return err;
 }
 
 static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
-				 const char *oldname, bool debug)
+				 const char *oldname)
 {
 	int err = vfs_symlink(dir, dentry, oldname);
-	if (debug)
-		pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
+
+	pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
 	return err;
 }
 
@@ -168,11 +165,8 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
 {
 	int err;
 
-	pr_debug("rename(%pd2, %pd2, 0x%x)\n",
-		 olddentry, newdentry, flags);
-
+	pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags);
 	err = vfs_rename(olddir, olddentry, newdir, newdentry, NULL, flags);
-
 	if (err) {
 		pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
 			 olddentry, newdentry, err);
@@ -334,12 +328,18 @@ int ovl_open_maybe_copy_up(struct dentry *dentry, unsigned int file_flags);
 int ovl_update_time(struct inode *inode, struct timespec *ts, int flags);
 bool ovl_is_private_xattr(const char *name);
 
+struct ovl_inode_params {
+	struct inode *newinode;
+	struct dentry *upperdentry;
+	struct ovl_path *lowerpath;
+	struct dentry *index;
+	unsigned int numlower;
+};
 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev);
 struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,
 			       bool is_upper);
-struct inode *ovl_get_inode(struct super_block *sb, struct dentry *upperdentry,
-			    struct ovl_path *lowerpath, struct dentry *index,
-			    unsigned int numlower);
+struct inode *ovl_get_inode(struct super_block *sb,
+			    struct ovl_inode_params *oip);
 static inline void ovl_copyattr(struct inode *from, struct inode *to)
 {
 	to->i_uid = from->i_uid;
@@ -352,18 +352,21 @@ static inline void ovl_copyattr(struct inode *from, struct inode *to)
 
 /* dir.c */
 extern const struct inode_operations ovl_dir_inode_operations;
-struct dentry *ovl_lookup_temp(struct dentry *workdir);
 int ovl_cleanup_and_whiteout(struct dentry *workdir, struct inode *dir,
 			     struct dentry *dentry);
-struct cattr {
+struct ovl_cattr {
 	dev_t rdev;
 	umode_t mode;
 	const char *link;
+	struct dentry *hardlink;
 };
-int ovl_create_real(struct inode *dir, struct dentry *newdentry,
-		    struct cattr *attr,
-		    struct dentry *hardlink, bool debug);
+
+#define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
+
+struct dentry *ovl_create_real(struct inode *dir, struct dentry *newdentry,
+			       struct ovl_cattr *attr);
 int ovl_cleanup(struct inode *dir, struct dentry *dentry);
+struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr);
 
 /* copy_up.c */
 int ovl_copy_up(struct dentry *dentry);

fs/overlayfs/super.c

@@ -611,11 +611,10 @@ static struct dentry *ovl_workdir_create(struct ovl_fs *ofs,
 			goto retry;
 		}
 
-		err = ovl_create_real(dir, work,
-				      &(struct cattr){.mode = S_IFDIR | 0},
-				      NULL, true);
-		if (err)
-			goto out_dput;
+		work = ovl_create_real(dir, work, OVL_CATTR(attr.ia_mode));
+		err = PTR_ERR(work);
+		if (IS_ERR(work))
+			goto out_err;
 
 		/*
 		 * Try to remove POSIX ACL xattrs from workdir.  We are good if:

include/linux/fs.h

@@ -2886,6 +2886,10 @@ extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
 		int (*test)(struct inode *, void *), void *data);
 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
 
+extern struct inode *inode_insert5(struct inode *inode, unsigned long hashval,
+		int (*test)(struct inode *, void *),
+		int (*set)(struct inode *, void *),
+		void *data);
 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
 extern struct inode * iget_locked(struct super_block *, unsigned long);
 extern struct inode *find_inode_nowait(struct super_block *,