netfilter: ipset: Fix oversized kvmalloc() calls

commit 7bbc3d385bd813077acaf0e6fdb2a86a901f5382 upstream.

The commit

commit 7661809d493b426e979f39ab512e3adf41fbcc69
Author: Linus Torvalds <torvalds@linux-foundation.org>
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: syzbot+3493b1873fb3ea827986@syzkaller.appspotmail.com
Reported-by: syzbot+2b8443c35458a617c904@syzkaller.appspotmail.com
Reported-by: syzbot+ee5cb15f4a0e85e0d54e@syzkaller.appspotmail.com
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h
index cd91c30f3e18025d826daa6d661ac667ffc9e380..098764060a34413bca7f2ebf0d74dca9761d77ab 100644 (file)
--- a/net/netfilter/ipset/ip_set_hash_gen.h
+++ b/net/netfilter/ipset/ip_set_hash_gen.h
@@ -104,11 +104,11 @@ htable_size(u8 hbits)
 {
        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;