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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 7DBCFC2F3BE for ; Mon, 21 Jan 2019 13:56:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4114D2087F for ; Mon, 21 Jan 2019 13:56:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079019; bh=GQZLVWYM+WeQ+095zxEWyI1My8t3xEjU0dLcwIBeJD8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=L+the/TDk5MAQjxRVk7DGsRJo+oMtnCiZzekR2S3DCgZrJNhHhb+jqWBlTInSLUAL lj/R01b4sLy6M8vl36WWN58Xp6niru9gW7rhHD41cU2YqdFWfYqW0x+mcdmaOcyJYa ALWdNermION1Kn8ppEU4rsFUe72qvHCCvXF29Me8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731599AbfAUN45 (ORCPT ); Mon, 21 Jan 2019 08:56:57 -0500 Received: from mail.kernel.org ([198.145.29.99]:42078 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731957AbfAUN4m (ORCPT ); Mon, 21 Jan 2019 08:56:42 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2A6292087F; Mon, 21 Jan 2019 13:56:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079000; bh=GQZLVWYM+WeQ+095zxEWyI1My8t3xEjU0dLcwIBeJD8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FH/Im6LIACEpTDW4mGvaHyEXd5sd2W4HiQTGDB25DdSaY9doBD9zNg0GwR23IUvnr JY4JFTd77P5+QN3IuNnBRNuQMMP75TWgsynQBJ9GXihuQtJ5eqsNBS04/Pyf3mIodc 0hrcVyZUStFJIkbdeXcucxWiQN3uE8Q8FsL2e2MU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+e01d94b5a4c266be6e4c@syzkaller.appspotmail.com, Ying Xue , "David S. Miller" Subject: [PATCH 4.9 41/51] tipc: fix uninit-value in tipc_nl_compat_link_reset_stats Date: Mon, 21 Jan 2019 14:44:37 +0100 Message-Id: <20190121122457.728897723@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190121122453.700446926@linuxfoundation.org> References: <20190121122453.700446926@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ying Xue commit 8b66fee7f8ee18f9c51260e7a43ab37db5177a05 upstream. syzbot reports following splat: BUG: KMSAN: uninit-value in strlen+0x3b/0xa0 lib/string.c:486 CPU: 1 PID: 11057 Comm: syz-executor0 Not tainted 4.20.0-rc7+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:295 strlen+0x3b/0xa0 lib/string.c:486 nla_put_string include/net/netlink.h:1154 [inline] tipc_nl_compat_link_reset_stats+0x1f0/0x360 net/tipc/netlink_compat.c:760 __tipc_nl_compat_doit net/tipc/netlink_compat.c:311 [inline] tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:344 tipc_nl_compat_handle net/tipc/netlink_compat.c:1107 [inline] tipc_nl_compat_recv+0x14d7/0x2760 net/tipc/netlink_compat.c:1210 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline] genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626 netlink_rcv_skb+0x444/0x640 net/netlink/af_netlink.c:2477 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0xf40/0x1020 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2557338c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f25573396d4 R13: 00000000004cb478 R14: 00000000004d86c8 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2759 [inline] __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x309/0xa20 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:998 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline] netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmsg net/socket.c:2154 [inline] __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2161 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 The uninitialised access happened in tipc_nl_compat_link_reset_stats: nla_put_string(skb, TIPC_NLA_LINK_NAME, name) This is because name string is not validated before it's used. Reported-by: syzbot+e01d94b5a4c266be6e4c@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/tipc/netlink_compat.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -87,6 +87,11 @@ static int tipc_skb_tailroom(struct sk_b return limit; } +static inline int TLV_GET_DATA_LEN(struct tlv_desc *tlv) +{ + return TLV_GET_LEN(tlv) - TLV_SPACE(0); +} + static int tipc_add_tlv(struct sk_buff *skb, u16 type, void *data, u16 len) { struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(skb); @@ -166,6 +171,11 @@ static struct sk_buff *tipc_get_err_tlv( return buf; } +static inline bool string_is_valid(char *s, int len) +{ + return memchr(s, '\0', len) ? true : false; +} + static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd, struct tipc_nl_compat_msg *msg, struct sk_buff *arg) @@ -741,6 +751,7 @@ static int tipc_nl_compat_link_reset_sta { char *name; struct nlattr *link; + int len; name = (char *)TLV_DATA(msg->req); @@ -748,6 +759,10 @@ static int tipc_nl_compat_link_reset_sta if (!link) return -EMSGSIZE; + len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_LINK_NAME); + if (!string_is_valid(name, len)) + return -EINVAL; + if (nla_put_string(skb, TIPC_NLA_LINK_NAME, name)) return -EMSGSIZE;