NFSD: fix bad length checking for backchannel

the length for backchannel checking should be multiplied by sizeof(__be32).

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 9a6d088247fd..acb95026ae3b 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1853,6 +1853,11 @@ static __be32 check_forechannel_attrs(struct nfsd4_channel_attrs *ca, struct nfs
         return nfs_ok;
 }
 
+#define NFSD_CB_MAX_REQ_SZ      ((NFS4_enc_cb_recall_sz + \
+                                 RPC_MAX_HEADER_WITH_AUTH) * sizeof(__be32))
+#define NFSD_CB_MAX_RESP_SZ     ((NFS4_dec_cb_recall_sz + \
+                                 RPC_MAX_REPHEADER_WITH_AUTH) * sizeof(__be32))
+
 static __be32 check_backchannel_attrs(struct nfsd4_channel_attrs *ca)
 {
         ca->headerpadsz = 0;
@@ -1863,9 +1868,9 @@ static __be32 check_backchannel_attrs(struct nfsd4_channel_attrs *ca)
          * less than 1k.  Tighten up this estimate in the unlikely event
          * it turns out to be a problem for some client:
          */
-        if (ca->maxreq_sz < NFS4_enc_cb_recall_sz + RPC_MAX_HEADER_WITH_AUTH)
+        if (ca->maxreq_sz < NFSD_CB_MAX_REQ_SZ)
                 return nfserr_toosmall;
-        if (ca->maxresp_sz < NFS4_dec_cb_recall_sz + RPC_MAX_REPHEADER_WITH_AUTH)
+        if (ca->maxresp_sz < NFSD_CB_MAX_RESP_SZ)
                 return nfserr_toosmall;
         ca->maxresp_cached = 0;
         if (ca->maxops < 2)