From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DBF07C4332D for ; Mon, 11 Jan 2021 13:37:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4E8D221EC for ; Mon, 11 Jan 2021 13:37:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730527AbhAKNhF (ORCPT ); Mon, 11 Jan 2021 08:37:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:60420 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731627AbhAKNN2 (ORCPT ); Mon, 11 Jan 2021 08:13:28 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1940321973; Mon, 11 Jan 2021 13:12:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610370767; bh=dTw/4c7vdboY41bKzNKv8RRdtWYMYkKxufFm7M1CimA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KczsJ3uR/6Soa5P9hwrvP0DIk5DVJK1wAmRQXrrhYT1KTEXDXxKfLs3L108mS1kTg Lv2mXgRUwmiItkVBT5ca7/h5aC9gH37FbnzLcrpTxPxjt2QbO7UZs4OqcQNjj3FN/B GEEz/LdwD/Vmb1DTkriIB1btOuieYoABoTjaNLFU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+d66bfadebca46cf61a2b@syzkaller.appspotmail.com, Vasily Averin , Jozsef Kadlecsik , Pablo Neira Ayuso Subject: [PATCH 5.4 88/92] netfilter: ipset: fix shift-out-of-bounds in htable_bits() Date: Mon, 11 Jan 2021 14:02:32 +0100 Message-Id: <20210111130043.400224281@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210111130039.165470698@linuxfoundation.org> References: <20210111130039.165470698@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vasily Averin commit 5c8193f568ae16f3242abad6518dc2ca6c8eef86 upstream. htable_bits() can call jhash_size(32) and trigger shift-out-of-bounds UBSAN: shift-out-of-bounds in net/netfilter/ipset/ip_set_hash_gen.h:151:6 shift exponent 32 is too large for 32-bit type 'unsigned int' CPU: 0 PID: 8498 Comm: syz-executor519 Not tainted 5.10.0-rc7-next-20201208-syzkaller #0 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:395 htable_bits net/netfilter/ipset/ip_set_hash_gen.h:151 [inline] hash_mac_create.cold+0x58/0x9b net/netfilter/ipset/ip_set_hash_gen.h:1524 ip_set_create+0x610/0x1380 net/netfilter/ipset/ip_set_core.c:1115 nfnetlink_rcv_msg+0xecc/0x1180 net/netfilter/nfnetlink.c:252 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 nfnetlink_rcv+0x1ac/0x420 net/netfilter/nfnetlink.c:600 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x907/0xe40 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2345 ___sys_sendmsg+0xf3/0x170 net/socket.c:2399 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2432 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This patch replaces htable_bits() by simple fls(hashsize - 1) call: it alone returns valid nbits both for round and non-round hashsizes. It is normal to set any nbits here because it is validated inside following htable_size() call which returns 0 for nbits>31. Fixes: 1feab10d7e6d("netfilter: ipset: Unified hash type generation") Reported-by: syzbot+d66bfadebca46cf61a2b@syzkaller.appspotmail.com Signed-off-by: Vasily Averin Acked-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/ipset/ip_set_hash_gen.h | 20 +++++--------------- 1 file changed, 5 insertions(+), 15 deletions(-) --- a/net/netfilter/ipset/ip_set_hash_gen.h +++ b/net/netfilter/ipset/ip_set_hash_gen.h @@ -143,20 +143,6 @@ htable_size(u8 hbits) return hsize * sizeof(struct hbucket *) + sizeof(struct htable); } -/* Compute htable_bits from the user input parameter hashsize */ -static u8 -htable_bits(u32 hashsize) -{ - /* Assume that hashsize == 2^htable_bits */ - u8 bits = fls(hashsize - 1); - - if (jhash_size(bits) != hashsize) - /* Round up to the first 2^n value */ - bits = fls(hashsize); - - return bits; -} - #ifdef IP_SET_HASH_WITH_NETS #if IPSET_NET_COUNT > 1 #define __CIDR(cidr, i) (cidr[i]) @@ -1520,7 +1506,11 @@ IPSET_TOKEN(HTYPE, _create)(struct net * if (!h) return -ENOMEM; - hbits = htable_bits(hashsize); + /* Compute htable_bits from the user input parameter hashsize. + * Assume that hashsize == 2^htable_bits, + * otherwise round up to the first 2^n value. + */ + hbits = fls(hashsize - 1); hsize = htable_size(hbits); if (hsize == 0) { kfree(h);