NFSv4: Handle NFS4ERR_WRONGSEC outside of nfs4_handle_exception()

I only want to try other secflavors during an initial mount if
NFS4ERR_WRONGSEC is returned.  nfs4_handle_exception() could
potentially map other errors to EPERM, so we should handle this
error specially for correctness.

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

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index e7e2077eebd9f623ce28a9714cb3f31988b2a941..628e35f7530751bc89174520000e3f13715de9c9 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2186,9 +2186,14 @@ static int nfs4_lookup_root(struct nfs_server *server, struct nfs_fh *fhandle,
        struct nfs4_exception exception = { };
        int err;
        do {
-               err = nfs4_handle_exception(server,
-                               _nfs4_lookup_root(server, fhandle, info),
-                               &exception);
+               err = _nfs4_lookup_root(server, fhandle, info);
+               switch (err) {
+               case 0:
+               case -NFS4ERR_WRONGSEC:
+                       break;
+               default:
+                       err = nfs4_handle_exception(server, err, &exception);
+               }
        } while (exception.retry);
        return err;
 }
@@ -2221,10 +2226,19 @@ static int nfs4_find_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
 
        for (i = 0; i < len; i++) {
                status = nfs4_lookup_root_sec(server, fhandle, info, flav_array[i]);
-               if (status == -EPERM || status == -EACCES)
+               if (status == -NFS4ERR_WRONGSEC || status == -EACCES)
                        continue;
                break;
        }
+       /*
+        * -EACCESS could mean that the user doesn't have correct permissions
+        * to access the mount.  It could also mean that we tried to mount
+        * with a gss auth flavor, but rpc.gssd isn't running.  Either way,
+        * existing mount programs don't handle -EACCES very well so it should
+        * be mapped to -EPERM instead.
+        */
+       if (status == -EACCES)
+               status = -EPERM;
        return status;
 }
 
@@ -2235,7 +2249,11 @@ static int nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
                              struct nfs_fsinfo *info)
 {
        int status = nfs4_lookup_root(server, fhandle, info);
-       if ((status == -EPERM) && !(server->flags & NFS_MOUNT_SECFLAVOUR))
+       if ((status == -NFS4ERR_WRONGSEC) && !(server->flags & NFS_MOUNT_SECFLAVOUR))
+               /*
+                * A status of -NFS4ERR_WRONGSEC will be mapped to -EPERM
+                * by nfs4_map_errors() as this function exits.
+                */
                status = nfs4_find_root_sec(server, fhandle, info);
        if (status == 0)
                status = nfs4_server_capabilities(server, fhandle);