bpf: reject invalid names right in ->lookup()

... and other methods won't see them at all

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2016-03-25 12:06:51 -04:00
parent 798434bda3
commit 0c93b7d85d

View File

@ -119,18 +119,10 @@ static int bpf_inode_type(const struct inode *inode, enum bpf_type *type)
return 0;
}
static bool bpf_dname_reserved(const struct dentry *dentry)
{
return strchr(dentry->d_name.name, '.');
}
static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct inode *inode;
if (bpf_dname_reserved(dentry))
return -EPERM;
inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFDIR);
if (IS_ERR(inode))
return PTR_ERR(inode);
@ -152,9 +144,6 @@ static int bpf_mkobj_ops(struct inode *dir, struct dentry *dentry,
{
struct inode *inode;
if (bpf_dname_reserved(dentry))
return -EPERM;
inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFREG);
if (IS_ERR(inode))
return PTR_ERR(inode);
@ -187,31 +176,21 @@ static int bpf_mkobj(struct inode *dir, struct dentry *dentry, umode_t mode,
}
}
static int bpf_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *new_dentry)
static struct dentry *
bpf_lookup(struct inode *dir, struct dentry *dentry, unsigned flags)
{
if (bpf_dname_reserved(new_dentry))
return -EPERM;
return simple_link(old_dentry, dir, new_dentry);
}
static int bpf_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
if (bpf_dname_reserved(new_dentry))
return -EPERM;
return simple_rename(old_dir, old_dentry, new_dir, new_dentry);
if (strchr(dentry->d_name.name, '.'))
return ERR_PTR(-EPERM);
return simple_lookup(dir, dentry, flags);
}
static const struct inode_operations bpf_dir_iops = {
.lookup = simple_lookup,
.lookup = bpf_lookup,
.mknod = bpf_mkobj,
.mkdir = bpf_mkdir,
.rmdir = simple_rmdir,
.rename = bpf_rename,
.link = bpf_link,
.rename = simple_rename,
.link = simple_link,
.unlink = simple_unlink,
};