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

[Luis Henriques <lhenriques@suse.de>]

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;
		}
	}

> +
>  	/* 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
>