NFSD: Error out when getting more than one fsloc/secinfo/uuid

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 7884051..13b85f9 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -389,6 +389,10 @@
 	int len;
 	int migrated, i, err;
 
+	/* more than one fsloc */
+	if (fsloc->locations)
+		return -EINVAL;
+
 	/* listsize */
 	err = get_uint(mesg, &fsloc->locations_count);
 	if (err)
@@ -442,6 +446,10 @@
 	u32 listsize;
 	int err;
 
+	/* more than one secinfo */
+	if (exp->ex_nflavors)
+		return -EINVAL;
+
 	err = get_uint(mesg, &listsize);
 	if (err)
 		return err;
@@ -481,6 +489,10 @@
 {
 	int len;
 
+	/* more than one uuid */
+	if (*puuid)
+		return -EINVAL;
+
 	/* expect a 16 byte uuid encoded as \xXXXX... */
 	len = qword_get(mesg, buf, PAGE_SIZE);
 	if (len != EX_UUID_LEN)