[PATCH] fuse: check directory aliasing in mkdir

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

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Miklos Szeredi 2005-11-28 13:44:16 -08:00 committed by Linus Torvalds
parent ea164d73a7
commit f007d5c961

View File

@ -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;
}
@ -874,14 +887,9 @@ 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);
iput(inode);
return ERR_PTR(-EIO);
}
if (inode && dir_alias(inode)) {
iput(inode);
return ERR_PTR(-EIO);
}
d_add(entry, inode);
return NULL;