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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 DC067C6778A for ; Sun, 1 Jul 2018 18:33:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94B3B216E3 for ; Sun, 1 Jul 2018 18:33:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94B3B216E3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933581AbeGASdj (ORCPT ); Sun, 1 Jul 2018 14:33:39 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60732 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933435AbeGAQQL (ORCPT ); Sun, 1 Jul 2018 12:16:11 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 24E92AD8; Sun, 1 Jul 2018 16:16:10 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julian Anastasov , Simon Horman , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 4.4 003/105] ipvs: fix buffer overflow with sync daemon and service Date: Sun, 1 Jul 2018 18:01:13 +0200 Message-Id: <20180701153149.664289093@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180701153149.382300170@linuxfoundation.org> References: <20180701153149.382300170@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Julian Anastasov [ Upstream commit 52f96757905bbf0edef47f3ee6c7c784e7f8ff8a ] syzkaller reports for buffer overflow for interface name when starting sync daemons [1] What we do is that we copy user structure into larger stack buffer but later we search NUL past the stack buffer. The same happens for sched_name when adding/editing virtual server. We are restricted by IP_VS_SCHEDNAME_MAXLEN and IP_VS_IFNAME_MAXLEN being used as size in include/uapi/linux/ip_vs.h, so they include the space for NUL. As using strlcpy is wrong for unsafe source, replace it with strscpy and add checks to return EINVAL if source string is not NUL-terminated. The incomplete strlcpy fix comes from 2.6.13. For the netlink interface reduce the len parameter for IPVS_DAEMON_ATTR_MCAST_IFN and IPVS_SVC_ATTR_SCHED_NAME, so that we get proper EINVAL. [1] kernel BUG at lib/string.c:1052! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 373 Comm: syz-executor936 Not tainted 4.17.0-rc4+ #45 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:fortify_panic+0x13/0x20 lib/string.c:1051 RSP: 0018:ffff8801c976f800 EFLAGS: 00010282 RAX: 0000000000000022 RBX: 0000000000000040 RCX: 0000000000000000 RDX: 0000000000000022 RSI: ffffffff8160f6f1 RDI: ffffed00392edef6 RBP: ffff8801c976f800 R08: ffff8801cf4c62c0 R09: ffffed003b5e4fb0 R10: ffffed003b5e4fb0 R11: ffff8801daf27d87 R12: ffff8801c976fa20 R13: ffff8801c976fae4 R14: ffff8801c976fae0 R15: 000000000000048b FS: 00007fd99f75e700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200001c0 CR3: 00000001d6843000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: strlen include/linux/string.h:270 [inline] strlcpy include/linux/string.h:293 [inline] do_ip_vs_set_ctl+0x31c/0x1d00 net/netfilter/ipvs/ip_vs_ctl.c:2388 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x7d/0xd0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0xd8/0xf0 net/ipv4/ip_sockglue.c:1253 udp_setsockopt+0x62/0xa0 net/ipv4/udp.c:2487 ipv6_setsockopt+0x149/0x170 net/ipv6/ipv6_sockglue.c:917 tcp_setsockopt+0x93/0xe0 net/ipv4/tcp.c:3057 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3046 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903 __do_sys_setsockopt net/socket.c:1914 [inline] __se_sys_setsockopt net/socket.c:1911 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x447369 RSP: 002b:00007fd99f75dda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00000000006e39e4 RCX: 0000000000447369 RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000018 R09: 0000000000000000 R10: 00000000200001c0 R11: 0000000000000246 R12: 00000000006e39e0 R13: 75a1ff93f0896195 R14: 6f745f3168746576 R15: 0000000000000001 Code: 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 48 89 df e8 d2 8f 48 fa eb de 55 48 89 fe 48 c7 c7 60 65 64 88 48 89 e5 e8 91 dd f3 f9 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 56 RIP: fortify_panic+0x13/0x20 lib/string.c:1051 RSP: ffff8801c976f800 Reported-and-tested-by: syzbot+aac887f77319868646df@syzkaller.appspotmail.com Fixes: e4ff67513096 ("ipvs: add sync_maxlen parameter for the sync daemon") Fixes: 4da62fc70d7c ("[IPVS]: Fix for overflows") Signed-off-by: Julian Anastasov Acked-by: Simon Horman Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/netfilter/ipvs/ip_vs_ctl.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -2349,8 +2349,10 @@ do_ip_vs_set_ctl(struct sock *sk, int cm struct ipvs_sync_daemon_cfg cfg; memset(&cfg, 0, sizeof(cfg)); - strlcpy(cfg.mcast_ifn, dm->mcast_ifn, - sizeof(cfg.mcast_ifn)); + ret = -EINVAL; + if (strscpy(cfg.mcast_ifn, dm->mcast_ifn, + sizeof(cfg.mcast_ifn)) <= 0) + goto out_dec; cfg.syncid = dm->syncid; ret = start_sync_thread(ipvs, &cfg, dm->state); } else { @@ -2388,12 +2390,19 @@ do_ip_vs_set_ctl(struct sock *sk, int cm } } + if ((cmd == IP_VS_SO_SET_ADD || cmd == IP_VS_SO_SET_EDIT) && + strnlen(usvc.sched_name, IP_VS_SCHEDNAME_MAXLEN) == + IP_VS_SCHEDNAME_MAXLEN) { + ret = -EINVAL; + goto out_unlock; + } + /* Check for valid protocol: TCP or UDP or SCTP, even for fwmark!=0 */ if (usvc.protocol != IPPROTO_TCP && usvc.protocol != IPPROTO_UDP && usvc.protocol != IPPROTO_SCTP) { - pr_err("set_ctl: invalid protocol: %d %pI4:%d %s\n", + pr_err("set_ctl: invalid protocol: %d %pI4:%d\n", usvc.protocol, &usvc.addr.ip, - ntohs(usvc.port), usvc.sched_name); + ntohs(usvc.port)); ret = -EFAULT; goto out_unlock; } @@ -2822,7 +2831,7 @@ static const struct nla_policy ip_vs_cmd static const struct nla_policy ip_vs_daemon_policy[IPVS_DAEMON_ATTR_MAX + 1] = { [IPVS_DAEMON_ATTR_STATE] = { .type = NLA_U32 }, [IPVS_DAEMON_ATTR_MCAST_IFN] = { .type = NLA_NUL_STRING, - .len = IP_VS_IFNAME_MAXLEN }, + .len = IP_VS_IFNAME_MAXLEN - 1 }, [IPVS_DAEMON_ATTR_SYNC_ID] = { .type = NLA_U32 }, [IPVS_DAEMON_ATTR_SYNC_MAXLEN] = { .type = NLA_U16 }, [IPVS_DAEMON_ATTR_MCAST_GROUP] = { .type = NLA_U32 }, @@ -2840,7 +2849,7 @@ static const struct nla_policy ip_vs_svc [IPVS_SVC_ATTR_PORT] = { .type = NLA_U16 }, [IPVS_SVC_ATTR_FWMARK] = { .type = NLA_U32 }, [IPVS_SVC_ATTR_SCHED_NAME] = { .type = NLA_NUL_STRING, - .len = IP_VS_SCHEDNAME_MAXLEN }, + .len = IP_VS_SCHEDNAME_MAXLEN - 1 }, [IPVS_SVC_ATTR_PE_NAME] = { .type = NLA_NUL_STRING, .len = IP_VS_PENAME_MAXLEN }, [IPVS_SVC_ATTR_FLAGS] = { .type = NLA_BINARY,