Commit f007d5c9 authored by Miklos Szeredi's avatar Miklos Szeredi Committed by Linus Torvalds
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[PATCH] fuse: check directory aliasing in mkdir 



Check the created directory inode for aliases in the mkdir() method.

Signed-off-by: default avatarMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent ea164d73

fs/fuse/dir.c

+17 −9
Original line number Diff line number Diff line
@@ -74,6 +74,19 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd) 
	return 1;

}



static int dir_alias(struct inode *inode)

{

	if (S_ISDIR(inode->i_mode)) {

		/* Don't allow creating an alias to a directory  */

		struct dentry *alias = d_find_alias(inode);

		if (alias) {

			dput(alias);

			return 1;

		}

	}

	return 0;

}



static struct dentry_operations fuse_dentry_operations = {

	.d_revalidate	= fuse_dentry_revalidate,

};
@@ -263,7 +276,7 @@ static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req, 
	fuse_put_request(fc, req);



	/* Don't allow userspace to do really stupid things... */

	if ((inode->i_mode ^ mode) & S_IFMT) {

	if (((inode->i_mode ^ mode) & S_IFMT) || dir_alias(inode)) {

		iput(inode);

		return -EIO;

	}
@@ -874,15 +887,10 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, 
	err = fuse_lookup_iget(dir, entry, &inode);

	if (err)

		return ERR_PTR(err);

	if (inode && S_ISDIR(inode->i_mode)) {

		/* Don't allow creating an alias to a directory  */

		struct dentry *alias = d_find_alias(inode);

		if (alias) {

			dput(alias);

	if (inode && dir_alias(inode)) {

		iput(inode);

		return ERR_PTR(-EIO);

	}

	}

	d_add(entry, inode);

	return NULL;

}