4 files changed, 58 insertions, 30 deletions

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index c1c9e035d4a4..b73baba3fb97 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -1320,6 +1320,23 @@ rqst_exp_parent(struct svc_rqst *rqstp, struct path *path)
         return exp;
 }
 
+static struct svc_export *find_fsidzero_export(struct svc_rqst *rqstp)
+{
+        struct svc_export *exp;
+        u32 fsidv[2];
+
+        mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
+
+        exp = rqst_exp_find(rqstp, FSID_NUM, fsidv);
+        /*
+         * We shouldn't have accepting an nfsv4 request at all if we
+         * don't have a pseudoexport!:
+         */
+        if (IS_ERR(exp) && PTR_ERR(exp) == -ENOENT)
+                exp = ERR_PTR(-ESERVERFAULT);
+        return exp;
+}
+
 /*
  * Called when we need the filehandle for the root of the pseudofs,
  * for a given NFSv4 client.   The root is defined to be the
@@ -1330,11 +1347,8 @@ exp_pseudoroot(struct svc_rqst *rqstp, struct svc_fh *fhp)
 {
         struct svc_export *exp;
         __be32 rv;
-        u32 fsidv[2];
-
-        mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
 
-        exp = rqst_exp_find(rqstp, FSID_NUM, fsidv);
+        exp = find_fsidzero_export(rqstp);
         if (IS_ERR(exp))
                 return nfserrno(PTR_ERR(exp));
         rv = fh_compose(fhp, exp, exp->ex_path.dentry, NULL);
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 2153f9bdbebd..fcb9817881a1 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -477,13 +477,14 @@ static int set_forechannel_drc_size(struct nfsd4_channel_attrs *fchan)
 
 /*
  * fchan holds the client values on input, and the server values on output
+ * sv_max_mesg is the maximum payload plus one page for overhead.
  */
 static int init_forechannel_attrs(struct svc_rqst *rqstp,
                                   struct nfsd4_channel_attrs *session_fchan,
                                   struct nfsd4_channel_attrs *fchan)
 {
         int status = 0;
-        __u32   maxcount = svc_max_payload(rqstp);
+        __u32   maxcount = nfsd_serv->sv_max_mesg;
 
         /* headerpadsz set to zero in encode routine */
 
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index 0eb9c820b7a6..c5393d1b8955 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -758,6 +758,7 @@ nfserrno (int errno)
                 { nfserr_io, -ETXTBSY },
                 { nfserr_notsupp, -EOPNOTSUPP },
                 { nfserr_toosmall, -ETOOSMALL },
+                { nfserr_serverfault, -ESERVERFAULT },
         };
         int     i;
 
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index a293f0273263..638573968dcf 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -141,6 +141,40 @@ out:
         return err;
 }
 
+static void follow_to_parent(struct path *path)
+{
+        struct dentry *dp;
+
+        while (path->dentry == path->mnt->mnt_root && follow_up(path))
+                ;
+        dp = dget_parent(path->dentry);
+        dput(path->dentry);
+        path->dentry = dp;
+}
+
+static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
+{
+        struct svc_export *exp2;
+        struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
+                            .dentry = dget(dparent)};
+
+        follow_to_parent(&path);
+
+        exp2 = rqst_exp_parent(rqstp, &path);
+        if (PTR_ERR(exp2) == -ENOENT) {
+                *dentryp = dget(dparent);
+        } else if (IS_ERR(exp2)) {
+                path_put(&path);
+                return PTR_ERR(exp2);
+        } else {
+                *dentryp = dget(path.dentry);
+                exp_put(*exp);
+                *exp = exp2;
+        }
+        path_put(&path);
+        return 0;
+}
+
 __be32
 nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
                    const char *name, unsigned int len,
@@ -169,35 +203,13 @@ nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
                         dentry = dget(dparent);
                 else if (dparent != exp->ex_path.dentry)
                         dentry = dget_parent(dparent);
-                else if (!EX_NOHIDE(exp))
+                else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
                         dentry = dget(dparent); /* .. == . just like at / */
                 else {
                         /* checking mountpoint crossing is very different when stepping up */
-                        struct svc_export *exp2 = NULL;
-                        struct dentry *dp;
-                        struct path path = {.mnt = mntget(exp->ex_path.mnt),
-                                            .dentry = dget(dparent)};
-
-                        while (path.dentry == path.mnt->mnt_root &&
-                               follow_up(&path))
-                                ;
-                        dp = dget_parent(path.dentry);
-                        dput(path.dentry);
-                        path.dentry = dp;
-
-                        exp2 = rqst_exp_parent(rqstp, &path);
-                        if (PTR_ERR(exp2) == -ENOENT) {
-                                dentry = dget(dparent);
-                        } else if (IS_ERR(exp2)) {
-                                host_err = PTR_ERR(exp2);
-                                path_put(&path);
+                        host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
+                        if (host_err)
                                 goto out_nfserr;
-                        } else {
-                                dentry = dget(path.dentry);
-                                exp_put(exp);
-                                exp = exp2;
-                        }
-                        path_put(&path);
                 }
         } else {
                 fh_lock(fhp);