diff --git a/net/sctp/auth.c b/net/sctp/auth.c
index 1fcb4cf..52db5f6 100644
--- a/net/sctp/auth.c
+++ b/net/sctp/auth.c
@@ -786,6 +786,9 @@
 	for (i = 0; i < hmacs->shmac_num_idents; i++) {
 		id = hmacs->shmac_idents[i];
 
+		if (id > SCTP_AUTH_HMAC_ID_MAX)
+			return -EOPNOTSUPP;
+
 		if (SCTP_AUTH_HMAC_ID_SHA1 == id)
 			has_sha1 = 1;
 
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 9b9b2c3..5ffb9de 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3086,6 +3086,7 @@
 				    int optlen)
 {
 	struct sctp_hmacalgo *hmacs;
+	u32 idents;
 	int err;
 
 	if (!sctp_auth_enable)
@@ -3103,8 +3104,9 @@
 		goto out;
 	}
 
-	if (hmacs->shmac_num_idents == 0 ||
-	    hmacs->shmac_num_idents > SCTP_AUTH_NUM_HMACS) {
+	idents = hmacs->shmac_num_idents;
+	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
+	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
 		err = -EINVAL;
 		goto out;
 	}