diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index bffc32406fbf..fa6d72131c19 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -592,13 +592,13 @@ static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr)
 
 	if (attr->ia_valid & ATTR_UID) {
 		*p++ = xdr_one;
-		*p++ = cpu_to_be32(attr->ia_uid);
+		*p++ = cpu_to_be32(from_kuid(&init_user_ns, attr->ia_uid));
 	} else
 		*p++ = xdr_zero;
 
 	if (attr->ia_valid & ATTR_GID) {
 		*p++ = xdr_one;
-		*p++ = cpu_to_be32(attr->ia_gid);
+		*p++ = cpu_to_be32(from_kgid(&init_user_ns, attr->ia_gid));
 	} else
 		*p++ = xdr_zero;
 
@@ -657,8 +657,12 @@ static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr)
 
 	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
 	fattr->nlink = be32_to_cpup(p++);
-	fattr->uid = be32_to_cpup(p++);
-	fattr->gid = be32_to_cpup(p++);
+	fattr->uid = make_kuid(&init_user_ns, be32_to_cpup(p++));
+	if (!uid_valid(fattr->uid))
+		goto out_uid;
+	fattr->gid = make_kgid(&init_user_ns, be32_to_cpup(p++));
+	if (!gid_valid(fattr->gid))
+		goto out_gid;
 
 	p = xdr_decode_size3(p, &fattr->size);
 	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
@@ -675,6 +679,12 @@ static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr)
 
 	fattr->valid |= NFS_ATTR_FATTR_V3;
 	return 0;
+out_uid:
+	dprintk("NFS: returned invalid uid\n");
+	return -EINVAL;
+out_gid:
+	dprintk("NFS: returned invalid gid\n");
+	return -EINVAL;
 out_overflow:
 	print_overflow_msg(__func__, xdr);
 	return -EIO;