netfilter: ipset: Fix oversized kvmalloc() calls

The commit

commit 7661809d493b426e979f39ab512e3adf41fbcc69
Author: Linus Torvalds <[e-mail]>
Date: Wed Jul 14 09:45:49 2021 -0700

mm: don't allow oversized kvmalloc() calls

limits the max allocatable memory via kvmalloc() to MAX_INT. Apply the
same limit in ipset.

Reported-by: [e-mail]
Reported-by: [e-mail]
Reported-by: [e-mail]
Signed-off-by: Jozsef Kadlecsik <[e-mail]>
Signed-off-by: Pablo Neira Ayuso <[e-mail]>

net/netfilter/ipset/ip_set_hash_gen.h

···
 {
 	size_t hsize;
 
-	/* We must fit both into u32 in jhash and size_t */
+	/* We must fit both into u32 in jhash and INT_MAX in kvmalloc_node() */
 	if (hbits > 31)
 		return 0;
 	hsize = jhash_size(hbits);
-	if ((((size_t)-1) - sizeof(struct htable)) / sizeof(struct hbucket *)
+	if ((INT_MAX - sizeof(struct htable)) / sizeof(struct hbucket *)
 	    < hsize)
 		return 0;