NFS: Do secinfo as part of lookup

Whenever lookup sees wrongsec do a secinfo and retry the lookup to find
attributes of the file or directory, such as "is this a referral
mountpoint?".  This also allows me to remove handling -NFS4ERR_WRONSEC
as part of getattr xdr decoding.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 47 insertions, 17 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index ff7571f12bb8..3d92fe6be780 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2528,39 +2528,69 @@ static int _nfs4_proc_lookup(struct rpc_clnt *clnt, struct inode *dir,
         return status;
 }
 
-void nfs_fixup_secinfo_attributes(struct nfs_fattr *fattr, struct nfs_fh *fh)
+static void nfs_fixup_secinfo_attributes(struct nfs_fattr *fattr)
 {
-        memset(fh, 0, sizeof(struct nfs_fh));
-        fattr->fsid.major = 1;
         fattr->valid |= NFS_ATTR_FATTR_TYPE | NFS_ATTR_FATTR_MODE |
-                NFS_ATTR_FATTR_NLINK | NFS_ATTR_FATTR_FSID | NFS_ATTR_FATTR_MOUNTPOINT;
+                NFS_ATTR_FATTR_NLINK | NFS_ATTR_FATTR_MOUNTPOINT;
         fattr->mode = S_IFDIR | S_IRUGO | S_IXUGO;
         fattr->nlink = 2;
 }
 
-static int nfs4_proc_lookup(struct rpc_clnt *clnt, struct inode *dir, struct qstr *name,
-                            struct nfs_fh *fhandle, struct nfs_fattr *fattr)
+static int nfs4_proc_lookup_common(struct rpc_clnt **clnt, struct inode *dir,
+                                   struct qstr *name, struct nfs_fh *fhandle,
+                                   struct nfs_fattr *fattr)
 {
         struct nfs4_exception exception = { };
+        struct rpc_clnt *client = *clnt;
         int err;
         do {
-                int status;
-
-                status = _nfs4_proc_lookup(clnt, dir, name, fhandle, fattr);
-                switch (status) {
+                err = _nfs4_proc_lookup(client, dir, name, fhandle, fattr);
+                switch (err) {
                 case -NFS4ERR_BADNAME:
-                        return -ENOENT;
+                        err = -ENOENT;
+                        goto out;
                 case -NFS4ERR_MOVED:
-                        return nfs4_get_referral(dir, name, fattr, fhandle);
+                        err = nfs4_get_referral(dir, name, fattr, fhandle);
+                        goto out;
                 case -NFS4ERR_WRONGSEC:
-                        nfs_fixup_secinfo_attributes(fattr, fhandle);
+                        err = -EPERM;
+                        if (client != *clnt)
+                                goto out;
+
+                        client = nfs4_create_sec_client(client, dir, name);
+                        if (IS_ERR(client))
+                                return PTR_ERR(client);
+
+                        exception.retry = 1;
+                        break;
+                default:
+                        err = nfs4_handle_exception(NFS_SERVER(dir), err, &exception);
                 }
-                err = nfs4_handle_exception(NFS_SERVER(dir),
-                                status, &exception);
         } while (exception.retry);
+
+out:
+        if (err == 0)
+                *clnt = client;
+        else if (client != *clnt)
+                rpc_shutdown_client(client);
+
         return err;
 }
 
+static int nfs4_proc_lookup(struct rpc_clnt *clnt, struct inode *dir, struct qstr *name,
+                            struct nfs_fh *fhandle, struct nfs_fattr *fattr)
+{
+        int status;
+        struct rpc_clnt *client = NFS_CLIENT(dir);
+
+        status = nfs4_proc_lookup_common(&client, dir, name, fhandle, fattr);
+        if (client != NFS_CLIENT(dir)) {
+                rpc_shutdown_client(client);
+                nfs_fixup_secinfo_attributes(fattr);
+        }
+        return status;
+}
+
 static int _nfs4_proc_access(struct inode *inode, struct nfs_access_entry *entry)
 {
         struct nfs_server *server = NFS_SERVER(inode);
@@ -4996,8 +5026,8 @@ static int _nfs4_proc_secinfo(struct inode *dir, const struct qstr *name, struct
         return status;
 }
 
-static int nfs4_proc_secinfo(struct inode *dir, const struct qstr *name,
-                struct nfs4_secinfo_flavors *flavors)
+int nfs4_proc_secinfo(struct inode *dir, const struct qstr *name,
+                      struct nfs4_secinfo_flavors *flavors)
 {
         struct nfs4_exception exception = { };
         int err;