Re: [PATCH 0/3] Don't store cred in nfs_access_entry

From: "NeilBrown" <neilb@suse.de>
To: "Trond Myklebust" <trond.myklebust@hammerspace.com>,
	"Anna Schumaker" <anna.schumaker@netapp.com>
Cc: linux-nfs@vger.kernel.org
Subject: Re: [PATCH 0/3] Don't store cred in nfs_access_entry
Date: Wed, 17 Nov 2021 07:49:22 +1100	[thread overview]
Message-ID: <163709576284.13692.2252149084412844753@noble.neil.brown.name> (raw)
In-Reply-To: <163278643081.17728.10586733395858659759.stgit@noble.brown>

Hi Trond/Anna,
 have you had a chance to look at these patches?

Thanks,
NeilBrown

On Tue, 28 Sep 2021, NeilBrown wrote:
> It turns out that storing a counted ref to 'struct cred' in
> nfs_access_entry wasn't a good choice.
> 'struct cred' contains counted references to 'struct key', and users
> have a quota on how many keys they can have.  Keeping a cred in a cache
> imposes on that quota.
> 
> The nfs access cache can keep a large number of entries, and keep them
> indefinitely.  This can cause a user to go over-quota.
> 
> This series removes the 'struct cred *' from nfs_access_entry and
> instead stores the uid, gid, and a pointer to the group info.
> This makes the nfs_access_entry 64 bits larger.
> 
> Thanks,
> NeilBrown
> 
> ---
> 
> NeilBrown (3):
>       NFS: change nfs_access_get_cached to only report the mask
>       NFS: pass cred explicitly for access tests
>       NFS: don't store 'struct cred *' in struct nfs_access_entry
> 
> 
>  fs/nfs/dir.c            | 63 ++++++++++++++++++++++++++++++++++-------
>  fs/nfs/nfs3proc.c       |  5 ++--
>  fs/nfs/nfs4proc.c       | 13 +++++----
>  include/linux/nfs_fs.h  |  6 ++--
>  include/linux/nfs_xdr.h |  2 +-
>  5 files changed, 67 insertions(+), 22 deletions(-)
> 
> --
> Signature
> 
> 