Re: [RFC PATCH v7 06/24] ceph: parse new fscrypt_auth and fscrypt_file fields in inode traces

[Xiubo Li <xiubli@redhat.com>]

On 7/7/21 10:56 PM, Luis Henriques wrote:
> On Wed, Jul 07, 2021 at 03:32:13PM +0100, Luis Henriques wrote:
>> On Wed, Jul 07, 2021 at 08:19:25AM -0400, Jeff Layton wrote:
>>> On Wed, 2021-07-07 at 19:19 +0800, Xiubo Li wrote:
>>>> On 7/7/21 6:47 PM, Luis Henriques wrote:
>>>>> On Fri, Jun 25, 2021 at 09:58:16AM -0400, Jeff Layton wrote:
>>>>>> ...and store them in the ceph_inode_info.
>>>>>>
>>>>>> Signed-off-by: Jeff Layton <jlayton@kernel.org>
>>>>>> ---
>>>>>>    fs/ceph/file.c       |  2 ++
>>>>>>    fs/ceph/inode.c      | 18 ++++++++++++++++++
>>>>>>    fs/ceph/mds_client.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
>>>>>>    fs/ceph/mds_client.h |  4 ++++
>>>>>>    fs/ceph/super.h      |  6 ++++++
>>>>>>    5 files changed, 74 insertions(+)
>>>>>>
>>>>>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
>>>>>> index 2cda398ba64d..ea0e85075b7b 100644
>>>>>> --- a/fs/ceph/file.c
>>>>>> +++ b/fs/ceph/file.c
>>>>>> @@ -592,6 +592,8 @@ static int ceph_finish_async_create(struct inode *dir, struct inode *inode,
>>>>>>    	iinfo.xattr_data = xattr_buf;
>>>>>>    	memset(iinfo.xattr_data, 0, iinfo.xattr_len);
>>>>>>    
>>>>>> +	/* FIXME: set fscrypt_auth and fscrypt_file */
>>>>>> +
>>>>>>    	in.ino = cpu_to_le64(vino.ino);
>>>>>>    	in.snapid = cpu_to_le64(CEPH_NOSNAP);
>>>>>>    	in.version = cpu_to_le64(1);	// ???
>>>>>> diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
>>>>>> index f62785e4dbcb..b620281ea65b 100644
>>>>>> --- a/fs/ceph/inode.c
>>>>>> +++ b/fs/ceph/inode.c
>>>>>> @@ -611,6 +611,13 @@ struct inode *ceph_alloc_inode(struct super_block *sb)
>>>>>>    
>>>>>>    	ci->i_meta_err = 0;
>>>>>>    
>>>>>> +#ifdef CONFIG_FS_ENCRYPTION
>>>>>> +	ci->fscrypt_auth = NULL;
>>>>>> +	ci->fscrypt_auth_len = 0;
>>>>>> +	ci->fscrypt_file = NULL;
>>>>>> +	ci->fscrypt_file_len = 0;
>>>>>> +#endif
>>>>>> +
>>>>>>    	return &ci->vfs_inode;
>>>>>>    }
>>>>>>    
>>>>>> @@ -619,6 +626,9 @@ void ceph_free_inode(struct inode *inode)
>>>>>>    	struct ceph_inode_info *ci = ceph_inode(inode);
>>>>>>    
>>>>>>    	kfree(ci->i_symlink);
>>>>>> +#ifdef CONFIG_FS_ENCRYPTION
>>>>>> +	kfree(ci->fscrypt_auth);
>>>>>> +#endif
>>>>>>    	kmem_cache_free(ceph_inode_cachep, ci);
>>>>>>    }
>>>>>>    
>>>>>> @@ -1021,6 +1031,14 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
>>>>>>    		xattr_blob = NULL;
>>>>>>    	}
>>>>>>    
>>>>>> +	if (iinfo->fscrypt_auth_len && !ci->fscrypt_auth) {
>>>>>> +		ci->fscrypt_auth_len = iinfo->fscrypt_auth_len;
>>>>>> +		ci->fscrypt_auth = iinfo->fscrypt_auth;
>>>>>> +		iinfo->fscrypt_auth = NULL;
>>>>>> +		iinfo->fscrypt_auth_len = 0;
>>>>>> +		inode_set_flags(inode, S_ENCRYPTED, S_ENCRYPTED);
>>>>>> +	}
>>>>> I think we also need to free iinfo->fscrypt_auth here if ci->fscrypt_auth
>>>>> is already set.  Something like:
>>>>>
>>>>> 	if (iinfo->fscrypt_auth_len) {
>>>>> 		if (!ci->fscrypt_auth) {
>>>>> 			...
>>>>> 		} else {
>>>>> 			kfree(iinfo->fscrypt_auth);
>>>>> 			iinfo->fscrypt_auth = NULL;
>>>>> 		}
>>>>> 	}
>>>>>
>>>> IMO, this should be okay because it will be freed in
>>>> destroy_reply_info() when putting the request.
>>>>
>>>>
>>> Yes. All of that should get cleaned up with the request.
>> Hmm... ok, so maybe I missed something because I *did* saw kmemleak
>> complaining.  Maybe it was on the READDIR path.  /me goes look again.
> Ah, that was indeed the problem.  So, here's a quick hack to fix
> destroy_reply_info() so that it also frees the extra memory from READDIR:
>
> @@ -686,12 +686,23 @@ static int parse_reply_info(struct ceph_mds_session *s, struct ceph_msg *msg,
>   
>   static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
>   {
> +	int i = 0;
> +
>   	kfree(info->diri.fscrypt_auth);
>   	kfree(info->diri.fscrypt_file);
>   	kfree(info->targeti.fscrypt_auth);
>   	kfree(info->targeti.fscrypt_file);
>   	if (!info->dir_entries)
>   		return;
> +
> +	for (i = 0; i < info->dir_nr; i++) {
> +		struct ceph_mds_reply_dir_entry *rde = info->dir_entries + i;
> +		if (rde->inode.fscrypt_auth_len)
> +			kfree(rde->inode.fscrypt_auth);
> +	}
> +	
>   	free_pages((unsigned long)info->dir_entries, get_order(info->dir_buf_size));
>   }
>   

Yeah, this looks nice.


> Cheers,
> --
> Luís
>