nfsd: dynamically skip encoded fattr bitmap in _nfsd4_verify

_nfsd4_verify currently skips 3 words from the encoded buffer begining.
With support for 3-word attr bitmaps in nfsd41, nfsd4_encode_fattr
may encode 1, 2, or 3 words, and not always 2 as it used to be, hence
we need to find out where to skip using the encoded bitmap length.

Note: This patch may be applied over pre-nfsd41 nfsd.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 52bb14debb30..937853f62834 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -775,7 +775,8 @@ _nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         if (status)
                 goto out_kfree;
 
-        p = buf + 3;
+        /* skip bitmap */
+        p = buf + 1 + ntohl(buf[0]);
         status = nfserr_not_same;
         if (ntohl(*p++) != verify->ve_attrlen)
                 goto out_kfree;