ext4: switch to fscrypt_get_symlink()

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Eric Biggers 2018-01-11 22:10:40 -05:00 committed by Theodore Ts'o
parent 78e1060c94
commit 6a9269c838

View File

@ -28,59 +28,28 @@ static const char *ext4_encrypted_get_link(struct dentry *dentry,
struct delayed_call *done)
{
struct page *cpage = NULL;
char *caddr, *paddr = NULL;
struct fscrypt_str cstr, pstr;
struct fscrypt_symlink_data *sd;
int res;
u32 max_size = inode->i_sb->s_blocksize;
const void *caddr;
unsigned int max_size;
const char *paddr;
if (!dentry)
return ERR_PTR(-ECHILD);
res = fscrypt_get_encryption_info(inode);
if (res)
return ERR_PTR(res);
if (ext4_inode_is_fast_symlink(inode)) {
caddr = (char *) EXT4_I(inode)->i_data;
caddr = EXT4_I(inode)->i_data;
max_size = sizeof(EXT4_I(inode)->i_data);
} else {
cpage = read_mapping_page(inode->i_mapping, 0, NULL);
if (IS_ERR(cpage))
return ERR_CAST(cpage);
caddr = page_address(cpage);
max_size = inode->i_sb->s_blocksize;
}
/* Symlink is encrypted */
sd = (struct fscrypt_symlink_data *)caddr;
cstr.name = sd->encrypted_path;
cstr.len = le16_to_cpu(sd->len);
if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) {
/* Symlink data on the disk is corrupted */
res = -EFSCORRUPTED;
goto errout;
}
res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
if (res)
goto errout;
paddr = pstr.name;
res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
if (res)
goto errout;
/* Null-terminate the name */
paddr[pstr.len] = '\0';
paddr = fscrypt_get_symlink(inode, caddr, max_size, done);
if (cpage)
put_page(cpage);
set_delayed_call(done, kfree_link, paddr);
return paddr;
errout:
if (cpage)
put_page(cpage);
kfree(paddr);
return ERR_PTR(res);
}
const struct inode_operations ext4_encrypted_symlink_inode_operations = {