6 files changed, 15 insertions, 11 deletions

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 2d786b813c7e..16e71d033ea5 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1261,13 +1261,13 @@ static void svcxdr_init_encode(struct svc_rqst *rqstp,
         xdr->buf = buf;
         xdr->iov = head;
         xdr->p   = head->iov_base + head->iov_len;
-        xdr->end = head->iov_base + PAGE_SIZE - 2 * RPC_MAX_AUTH_SIZE;
+        xdr->end = head->iov_base + PAGE_SIZE - rqstp->rq_auth_slack;
         /* Tail and page_len should be zero at this point: */
         buf->len = buf->head[0].iov_len;
         xdr->scratch.iov_len = 0;
         xdr->page_ptr = buf->pages;
         buf->buflen = PAGE_SIZE * (1 + rqstp->rq_page_end - buf->pages)
-                - 2 * RPC_MAX_AUTH_SIZE;
+                - rqstp->rq_auth_slack;
 }
 
 /*
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 62b882dc48ec..d0a016a502be 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2288,7 +2288,7 @@ nfsd4_sequence(struct svc_rqst *rqstp,
                         session->se_fchannel.maxresp_sz;
         status = (seq->cachethis) ? nfserr_rep_too_big_to_cache :
                                     nfserr_rep_too_big;
-        if (xdr_restrict_buflen(xdr, buflen - 2 * RPC_MAX_AUTH_SIZE))
+        if (xdr_restrict_buflen(xdr, buflen - rqstp->rq_auth_slack))
                 goto out_put_session;
         svc_reserve(rqstp, buflen);
 
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 3e347a1caec4..470fe8998c9b 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1611,7 +1611,8 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
         DECODE_HEAD;
         struct nfsd4_op *op;
         bool cachethis = false;
-        int max_reply = 2 * RPC_MAX_AUTH_SIZE + 8; /* opcnt, status */
+        int auth_slack= argp->rqstp->rq_auth_slack;
+        int max_reply = auth_slack + 8; /* opcnt, status */
         int readcount = 0;
         int readbytes = 0;
         int i;
@@ -1677,7 +1678,7 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
         svc_reserve(argp->rqstp, max_reply + readbytes);
         argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
 
-        if (readcount > 1 || max_reply > PAGE_SIZE - 2*RPC_MAX_AUTH_SIZE)
+        if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
                 argp->rqstp->rq_splice_ok = false;
 
         DECODE_TAIL;
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 85cb6472a423..1bc7cd05b22e 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -260,7 +260,10 @@ struct svc_rqst {
         void *                  rq_argp;        /* decoded arguments */
         void *                  rq_resp;        /* xdr'd results */
         void *                  rq_auth_data;   /* flavor-specific data */
-
+        int                     rq_auth_slack;  /* extra space xdr code
+                                                 * should leave in head
+                                                 * for krb5i, krb5p.
+                                                 */
         int                     rq_reserved;    /* space on socket outq
                                                  * reserved for this request
                                                  */
@@ -456,11 +459,7 @@ char *		   svc_print_addr(struct svc_rqst *, char *, size_t);
  */
 static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space)
 {
-        int added_space = 0;
-
-        if (rqstp->rq_authop->flavour)
-                added_space = RPC_MAX_AUTH_SIZE;
-        svc_reserve(rqstp, space + added_space);
+        svc_reserve(rqstp, space + rqstp->rq_auth_slack);
 }
 
 #endif /* SUNRPC_SVC_H */
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 0f73f4507746..4ce5eccec1f6 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1503,6 +1503,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
                         if (unwrap_integ_data(rqstp, &rqstp->rq_arg,
                                         gc->gc_seq, rsci->mechctx))
                                 goto garbage_args;
+                        rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
                         break;
                 case RPC_GSS_SVC_PRIVACY:
                         /* placeholders for length and seq. number: */
@@ -1511,6 +1512,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
                         if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
                                         gc->gc_seq, rsci->mechctx))
                                 goto garbage_args;
+                        rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
                         break;
                 default:
                         goto auth_err;
diff --git a/net/sunrpc/svcauth.c b/net/sunrpc/svcauth.c
index 2af7b0cba43a..79c0f3459b5c 100644
--- a/net/sunrpc/svcauth.c
+++ b/net/sunrpc/svcauth.c
@@ -54,6 +54,8 @@ svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
         }
         spin_unlock(&authtab_lock);
 
+        rqstp->rq_auth_slack = 0;
+
         rqstp->rq_authop = aops;
         return aops->accept(rqstp, authp);
 }