1 files changed, 64 insertions, 34 deletions

diff --git a/fs/namei.c b/fs/namei.c
index b4589922c0de..85d19e6cc8c0 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -265,7 +265,7 @@ static int check_acl(struct inode *inode, int mask)
 	        if (!acl)
 	                return -EAGAIN;
 		/* no ->get_acl() calls in RCU mode... */
-		if (acl == ACL_NOT_CACHED)
+		if (is_uncached_acl(acl))
 			return -ECHILD;
 	        return posix_acl_permission(inode, acl, mask & ~MAY_NOT_BLOCK);
 	}
@@ -1603,32 +1603,42 @@ static struct dentry *lookup_slow(const struct qstr *name,
 				  struct dentry *dir,
 				  unsigned int flags)
 {
-	struct dentry *dentry;
-	inode_lock(dir->d_inode);
-	dentry = d_lookup(dir, name);
-	if (unlikely(dentry)) {
+	struct dentry *dentry = ERR_PTR(-ENOENT), *old;
+	struct inode *inode = dir->d_inode;
+	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
+
+	inode_lock_shared(inode);
+	/* Don't go there if it's already dead */
+	if (unlikely(IS_DEADDIR(inode)))
+		goto out;
+again:
+	dentry = d_alloc_parallel(dir, name, &wq);
+	if (IS_ERR(dentry))
+		goto out;
+	if (unlikely(!d_in_lookup(dentry))) {
 		if ((dentry->d_flags & DCACHE_OP_REVALIDATE) &&
 		    !(flags & LOOKUP_NO_REVAL)) {
 			int error = d_revalidate(dentry, flags);
 			if (unlikely(error <= 0)) {
-				if (!error)
+				if (!error) {
 					d_invalidate(dentry);
+					dput(dentry);
+					goto again;
+				}
 				dput(dentry);
 				dentry = ERR_PTR(error);
 			}
 		}
-		if (dentry) {
-			inode_unlock(dir->d_inode);
-			return dentry;
+	} else {
+		old = inode->i_op->lookup(inode, dentry, flags);
+		d_lookup_done(dentry);
+		if (unlikely(old)) {
+			dput(dentry);
+			dentry = old;
 		}
 	}
-	dentry = d_alloc(dir, name);
-	if (unlikely(!dentry)) {
-		inode_unlock(dir->d_inode);
-		return ERR_PTR(-ENOMEM);
-	}
-	dentry = lookup_real(dir->d_inode, dentry, flags);
-	inode_unlock(dir->d_inode);
+out:
+	inode_unlock_shared(inode);
 	return dentry;
 }
 
@@ -2655,7 +2665,7 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
 		return NULL;
 	}
 
-	mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
+	mutex_lock(&p1->d_sb->s_vfs_rename_mutex);
 
 	p = d_ancestor(p2, p1);
 	if (p) {
@@ -2682,7 +2692,7 @@ void unlock_rename(struct dentry *p1, struct dentry *p2)
 	inode_unlock(p1->d_inode);
 	if (p1 != p2) {
 		inode_unlock(p2->d_inode);
-		mutex_unlock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
+		mutex_unlock(&p1->d_sb->s_vfs_rename_mutex);
 	}
 }
 EXPORT_SYMBOL(unlock_rename);
@@ -2828,12 +2838,6 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 
 	BUG_ON(dentry->d_inode);
 
-	/* Don't create child dentry for a dead directory. */
-	if (unlikely(IS_DEADDIR(dir))) {
-		error = -ENOENT;
-		goto out;
-	}
-
 	mode = op->mode;
 	if ((open_flag & O_CREAT) && !IS_POSIXACL(dir))
 		mode &= ~current_umask();
@@ -2982,6 +2986,9 @@ static int lookup_open(struct nameidata *nd, struct path *path,
 	int error;
 	bool need_lookup = false;
 
+	if (unlikely(IS_DEADDIR(dir_inode)))
+		return -ENOENT;
+
 	*opened &= ~FILE_CREATED;
 	dentry = lookup_dcache(&nd->last, dir, nd->flags);
 	if (IS_ERR(dentry))
@@ -2997,7 +3004,7 @@ static int lookup_open(struct nameidata *nd, struct path *path,
 		goto out_no_open;
 	}
 
-	if ((nd->flags & LOOKUP_OPEN) && dir_inode->i_op->atomic_open) {
+	if (dir_inode->i_op->atomic_open) {
 		return atomic_open(nd, dentry, path, file, op, got_write,
 				   need_lookup, opened);
 	}
@@ -3027,13 +3034,19 @@ static int lookup_open(struct nameidata *nd, struct path *path,
 			goto out_dput;
 		}
 		*opened |= FILE_CREATED;
-		error = security_path_mknod(&nd->path, dentry, mode, 0);
+		audit_inode_child(dir_inode, dentry, AUDIT_TYPE_CHILD_CREATE);
+		error = may_o_create(&nd->path, dentry, mode);
 		if (error)
 			goto out_dput;
-		error = vfs_create(dir->d_inode, dentry, mode,
-				   nd->flags & LOOKUP_EXCL);
+		if (!dir_inode->i_op->create) {
+			error = -EACCES;
+			goto out_dput;
+		}
+		error = dir_inode->i_op->create(dir_inode, dentry, mode,
+						op->open_flag & O_EXCL);
 		if (error)
 			goto out_dput;
+		fsnotify_create(dir_inode, dentry);
 	}
 out_no_open:
 	path->dentry = dentry;
@@ -3197,7 +3210,7 @@ finish_open:
 		return error;
 	}
 	audit_inode(nd->name, nd->path.dentry, 0);
-	if (unlikely(d_is_symlink(nd->path.dentry)) && !(open_flag & O_PATH)) {
+	if (unlikely(d_is_symlink(nd->path.dentry))) {
 		error = -ELOOP;
 		goto out;
 	}
@@ -3217,11 +3230,9 @@ finish_open:
 		got_write = true;
 	}
 finish_open_created:
-	if (likely(!(open_flag & O_PATH))) {
-		error = may_open(&nd->path, acc_mode, open_flag);
-		if (error)
-			goto out;
-	}
+	error = may_open(&nd->path, acc_mode, open_flag);
+	if (error)
+		goto out;
 	BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */
 	error = vfs_open(&nd->path, file, current_cred());
 	if (!error) {
@@ -3335,6 +3346,18 @@ out:
 	return error;
 }
 
+static int do_o_path(struct nameidata *nd, unsigned flags, struct file *file)
+{
+	struct path path;
+	int error = path_lookupat(nd, flags, &path);
+	if (!error) {
+		audit_inode(nd->name, path.dentry, 0);
+		error = vfs_open(&path, file, current_cred());
+		path_put(&path);
+	}
+	return error;
+}
+
 static struct file *path_openat(struct nameidata *nd,
 			const struct open_flags *op, unsigned flags)
 {
@@ -3354,6 +3377,13 @@ static struct file *path_openat(struct nameidata *nd,
 		goto out2;
 	}
 
+	if (unlikely(file->f_flags & O_PATH)) {
+		error = do_o_path(nd, flags, file);
+		if (!error)
+			opened |= FILE_OPENED;
+		goto out2;
+	}
+
 	s = path_init(nd, flags);
 	if (IS_ERR(s)) {
 		put_filp(file);