index c2f8e69d7d7a..9b5d2d87f836 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1650,6 +1650,13 @@ static int __ip6_append_data(struct sock *sk,
                                 err = -EINVAL;
                                 goto error;
                         }
+                       if (unlikely(alloclen < fraglen)) {
+                               if (printk_ratelimit())
+                                       pr_warn("%s: wrong alloclen: %d, 
+                                               __func__, alloclen, fraglen);
+                               alloclen = fraglen;
+                       }
+
                         if (transhdrlen) {
                                 skb = sock_alloc_send_skb(sk, alloclen,
                                                 (flags & MSG_DONTWAIT), &err);