nfsd xdr fixes

nfsd xdr fixes

[J. Bruce Fields]

The following are some small patches for bugs found while working on the
xdr code.

--b.

[PATCH 1/5] nfsd4: buffer-length check for SUPPATTR_EXCLCREAT

[J. Bruce Fields]

From: "J. Bruce Fields" <bfields@redhat.com>

This was an omission from 8c18f2052e756e7d5dea712fc6e7ed70c00e8a39
"nfsd41: SUPPATTR_EXCLCREAT attribute".

Cc: stable@vger.kernel.org
Cc: Benny Halevy <bhalevy@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4xdr.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 63f2395..668bfe1 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2483,6 +2483,8 @@ out_acl:
 			goto out;
 	}
 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
+		if ((buflen -= 16) < 0)
+			goto out_resource;
 		WRITE32(3);
 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
-- 
1.7.9.5

[PATCH 2/5] nfsd4: leave reply buffer space for failed setattr

[J. Bruce Fields]

From: "J. Bruce Fields" <bfields@redhat.com>

This fixes an ommission from 18032ca062e621e15683cb61c066ef3dc5414a7b
"NFSD: Server implementation of MAC Labeling", which increased the size
of the setattr error reply without increasing COMPOUND_ERR_SLACK_SPACE.

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfsd.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 30f34ab..479eb68 100644
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -282,7 +282,7 @@ void		nfsd_lockd_shutdown(void);
  * reason.
  */
 #define	COMPOUND_SLACK_SPACE		140    /* OP_GETFH */
-#define COMPOUND_ERR_SLACK_SPACE	12     /* OP_SETATTR */
+#define COMPOUND_ERR_SLACK_SPACE	16     /* OP_SETATTR */
 
 #define NFSD_LAUNDROMAT_MINTIMEOUT      1   /* seconds */
 
-- 
1.7.9.5

[PATCH 3/5] nfsd4: fix test_stateid error reply encoding

[J. Bruce Fields]

From: "J. Bruce Fields" <bfields@redhat.com>

If the entire operation fails then there's nothing to encode.

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4xdr.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 668bfe1..d214359 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3473,6 +3473,9 @@ nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
 	struct nfsd4_test_stateid_id *stateid, *next;
 	__be32 *p;
 
+	if (nfserr)
+		return nfserr;
+
 	RESERVE_SPACE(4 + (4 * test_stateid->ts_num_ids));
 	*p++ = htonl(test_stateid->ts_num_ids);
 
-- 
1.7.9.5

[PATCH 4/5] nfsd4: session needs room for following op to error out

[J. Bruce Fields]

From: "J. Bruce Fields" <bfields@redhat.com>

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4proc.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 82189b2..b9048e5 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1359,6 +1359,12 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
 		/* If op is non-idempotent */
 		if (opdesc->op_flags & OP_MODIFIES_SOMETHING) {
 			plen = opdesc->op_rsize_bop(rqstp, op);
+			/*
+			 * If there's still another operation, make sure
+			 * we'll have space to at least encode an error:
+			 */
+			if (resp->opcnt < args->opcnt)
+				plen += COMPOUND_ERR_SLACK_SPACE;
 			op->status = nfsd4_check_resp_size(resp, plen);
 		}
 
-- 
1.7.9.5

[PATCH 5/5] nfsd4: make set of large acl return efbig, not resource

[J. Bruce Fields]

From: "J. Bruce Fields" <bfields@redhat.com>

If a client attempts to set an excessively large ACL, return
NFS4ERR_FBIG instead of NFS4ERR_RESOURCE.  I'm not sure FBIG is correct,
but I'm positive RESOURCE is wrong (it isn't even a well-defined error
any more for NFS versions since 4.1).

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4xdr.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index d214359..aa04a6a 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -294,7 +294,7 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
 		READ32(nace);
 
 		if (nace > NFS4_ACL_MAX)
-			return nfserr_resource;
+			return nfserr_fbig;
 
 		*acl = nfs4_acl_new(nace);
 		if (*acl == NULL)
-- 
1.7.9.5

Re: [PATCH 1/5] nfsd4: buffer-length check for SUPPATTR_EXCLCREAT

[Benny Halevy]

On 02/24/2014 02:08 PM, J. Bruce Fields wrote:
> From: "J. Bruce Fields" <bfields@redhat.com>
>
> This was an omission from 8c18f2052e756e7d5dea712fc6e7ed70c00e8a39
> "nfsd41: SUPPATTR_EXCLCREAT attribute".
>
> Cc: stable@vger.kernel.org
> Cc: Benny Halevy <bhalevy@primarydata.com>

Ack.
Thanks for fixing!

Benny

> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> ---
>  fs/nfsd/nfs4xdr.c |    2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index 63f2395..668bfe1 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -2483,6 +2483,8 @@ out_acl:
>  			goto out;
>  	}
>  	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
> +		if ((buflen -= 16) < 0)
> +			goto out_resource;
>  		WRITE32(3);
>  		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
>  		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD1);