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 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.


>> +
>>   	/* finally update i_version */
>>   	if (le64_to_cpu(info->version) > ci->i_version)
>>   		ci->i_version = le64_to_cpu(info->version);
>> diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
>> index 3b3a14024ca0..9c994effc51d 100644
>> --- a/fs/ceph/mds_client.c
>> +++ b/fs/ceph/mds_client.c
>> @@ -183,8 +183,48 @@ static int parse_reply_info_in(void **p, void *end,
>>   			info->rsnaps = 0;
>>   		}
>>   
>> +		if (struct_v >= 5) {
>> +			u32 alen;
>> +
>> +			ceph_decode_32_safe(p, end, alen, bad);
>> +
>> +			while (alen--) {
>> +				u32 len;
>> +
>> +				/* key */
>> +				ceph_decode_32_safe(p, end, len, bad);
>> +				ceph_decode_skip_n(p, end, len, bad);
>> +				/* value */
>> +				ceph_decode_32_safe(p, end, len, bad);
>> +				ceph_decode_skip_n(p, end, len, bad);
>> +			}
>> +		}
>> +
>> +		/* fscrypt flag -- ignore */
>> +		if (struct_v >= 6)
>> +			ceph_decode_skip_8(p, end, bad);
>> +
>> +		if (struct_v >= 7) {
>> +			ceph_decode_32_safe(p, end, info->fscrypt_auth_len, bad);
>> +			if (info->fscrypt_auth_len) {
>> +				info->fscrypt_auth = kmalloc(info->fscrypt_auth_len, GFP_KERNEL);
>> +				if (!info->fscrypt_auth)
>> +					return -ENOMEM;
>> +				ceph_decode_copy_safe(p, end, info->fscrypt_auth,
>> +						      info->fscrypt_auth_len, bad);
>> +			}
>> +			ceph_decode_32_safe(p, end, info->fscrypt_file_len, bad);
>> +			if (info->fscrypt_file_len) {
>> +				info->fscrypt_file = kmalloc(info->fscrypt_file_len, GFP_KERNEL);
>> +				if (!info->fscrypt_file)
>> +					return -ENOMEM;
> As Xiubo already pointed out, there's a kfree(info->fscrypt_auth) missing
> in this error path.
>
> Cheers,
> --
> Luís
>
>> +				ceph_decode_copy_safe(p, end, info->fscrypt_file,
>> +						      info->fscrypt_file_len, bad);
>> +			}
>> +		}
>>   		*p = end;
>>   	} else {
>> +		/* legacy (unversioned) struct */
>>   		if (features & CEPH_FEATURE_MDS_INLINE_DATA) {
>>   			ceph_decode_64_safe(p, end, info->inline_version, bad);
>>   			ceph_decode_32_safe(p, end, info->inline_len, bad);
>> @@ -625,6 +665,10 @@ 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)
>>   {
>> +	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;
>>   	free_pages((unsigned long)info->dir_entries, get_order(info->dir_buf_size));
>> diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
>> index 64ea9d853b8d..0c3cc61fd038 100644
>> --- a/fs/ceph/mds_client.h
>> +++ b/fs/ceph/mds_client.h
>> @@ -88,6 +88,10 @@ struct ceph_mds_reply_info_in {
>>   	s32 dir_pin;
>>   	struct ceph_timespec btime;
>>   	struct ceph_timespec snap_btime;
>> +	u8 *fscrypt_auth;
>> +	u8 *fscrypt_file;
>> +	u32 fscrypt_auth_len;
>> +	u32 fscrypt_file_len;
>>   	u64 rsnaps;
>>   	u64 change_attr;
>>   };
>> diff --git a/fs/ceph/super.h b/fs/ceph/super.h
>> index 0cd94b296f5f..e032737fe472 100644
>> --- a/fs/ceph/super.h
>> +++ b/fs/ceph/super.h
>> @@ -429,6 +429,12 @@ struct ceph_inode_info {
>>   
>>   #ifdef CONFIG_CEPH_FSCACHE
>>   	struct fscache_cookie *fscache;
>> +#endif
>> +#ifdef CONFIG_FS_ENCRYPTION
>> +	u32 fscrypt_auth_len;
>> +	u32 fscrypt_file_len;
>> +	u8 *fscrypt_auth;
>> +	u8 *fscrypt_file;
>>   #endif
>>   	errseq_t i_meta_err;
>>   
>> -- 
>> 2.31.1
>>