netfilter: nf_tables: Fix oversized kvmalloc() calls

The commit 7661809d49 ("mm: don't allow oversized kvmalloc() calls")
limits the max allocatable memory via kvmalloc() to MAX_INT.

Reported-by: syzbot+cd43695a64bcd21b8596@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_tables_api.c

@@ -4336,7 +4336,7 @@ static int nf_tables_newset(struct sk_buff *skb, const struct nfnl_info *info,
 	if (ops->privsize != NULL)
 		size = ops->privsize(nla, &desc);
 	alloc_size = sizeof(*set) + size + udlen;
-	if (alloc_size < size)
+	if (alloc_size < size || alloc_size > INT_MAX)
 		return -ENOMEM;
 	set = kvzalloc(alloc_size, GFP_KERNEL);
 	if (!set)