Re: Problems with default ACLs over NFS

From: Suresh Jayaraman
Date: Mon Apr 20 2009 - 00:42:35 EST


hooanon05@xxxxxxxxxxx wrote:
>> On Mon, 23 Mar 2009 22:24:27 +0100 "J.A. Magall__n" <jamagallon@xxxxxxx> wrote:
>>
>>> Hi all...
>>>
>>> I have a strange problem with 2.6.29-rc8-git3.
>>> It looks like a kernel bug... ?
>>>
>>> I have a box with NFS autofs-mounted home directories. Server is a
>>> Solaris 10 system. This worked in previous kernel versions, so I
>>> don't blame Solaris, at this moment.
>>>
>>> With this acls set in my home:
> :::
>>> I get this strange message in the linux client:
>>>
>>> cicely:~> mkdir kk
>>> mkdir: cannot create directory `kk': Invalid argument

The following patch from Trond should fix this issue, I think.


From: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
Date: Wed, 15 Apr 2009 13:58:45 -0400
Subject: [PATCH] NFS: Fix the XDR iovec calculation in nfs3_xdr_setaclargs

Commit ae46141ff08f1965b17c531b571953c39ce8b9e2 (NFSv3: Fix posix ACL code)
introduces a bug in the calculation of the XDR header iovec. In the case
where we are inlining the acls, we need to adjust the length of the iovec
req->rq_svec, in addition to adjusting the total buffer length.

Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
---
fs/nfs/nfs3xdr.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index e6a1932..35869a4 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -713,7 +713,8 @@ nfs3_xdr_setaclargs(struct rpc_rqst *req, __be32 *p,
if (args->npages != 0)
xdr_encode_pages(buf, args->pages, 0, args->len);
else
- req->rq_slen += args->len;
+ req->rq_slen = xdr_adjust_iovec(req->rq_svec,
+ p + XDR_QUADLEN(args->len));

err = nfsacl_encode(buf, base, args->inode,
(args->mask & NFS_ACL) ?



> Tracing some kernel functions, I observed several thigs.
> - xdr_buf_subsegment() returned -1 due to 'len' is not 0.
> - xdr_encode_word() call from nfsacl_encode() got this -1, and
> nfsacl_encode/nfs3_xdr_setaclargs/nfs3_proc_setacls/nfs3_proc_setacl/nfs3_setxattr
> returned -EINVAL.
>
>
> Finally I am afraid this commit might be related to this issue.
>
> commit ae46141ff08f1965b17c531b571953c39ce8b9e2
> Author: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
> Date: Tue Mar 10 20:33:18 2009 -0400
>
> NFSv3: Fix posix ACL code
>
> Fix a memory leak due to allocation in the XDR layer. In cases where the
> RPC call needs to be retransmitted, we end up allocating new pages without
> clearing the old ones. Fix this by moving the allocation into
> nfs3_proc_setacls().
>
> Also fix an issue discovered by Kevin Rudd, whereby the amount of memory
> reserved for the acls in the xdr_buf->head was miscalculated, and causing
> corruption.
>
>
>
> J. R. Okajima
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html


--
Suresh Jayaraman
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/