diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index c29b6ed..1578d7a 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1588,6 +1588,10 @@
 		int err = get_write_access(inode);
 		if (err)
 			return nfserrno(err);
+		err = mnt_want_write(cur_fh->fh_export->ex_path.mnt);
+		if (err)
+			return nfserrno(err);
+		file_take_write(filp);
 	}
 	status = nfsd4_truncate(rqstp, cur_fh, open);
 	if (status) {