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=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 1D42AC2F3BE for ; Mon, 21 Jan 2019 13:59:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D882E2087F for ; Mon, 21 Jan 2019 13:58:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079140; bh=/ayrwnttDrSNYXOrj2rM9VDhjdwwq9CeF23sstG4PXg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Nc3wlI+h0rJmQMIwg8QN5Ys5aDGBw2cUSwvT0v9ON+JmT4jy9GBu4pWdmrg7Mnj/i WR1+kAzZYDnRpmLSBf4KKweEP3XHhH4JEo+8GBiZJ5GPmbmqaUK1NYejznOAumLq+K dj/+xauuTqJYv/CtU0wI+ySFeCDaFW1enRXBJBGI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732106AbfAUN66 (ORCPT ); Mon, 21 Jan 2019 08:58:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:44716 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732090AbfAUN64 (ORCPT ); Mon, 21 Jan 2019 08:58:56 -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 11F0F2084C; Mon, 21 Jan 2019 13:58:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079134; bh=/ayrwnttDrSNYXOrj2rM9VDhjdwwq9CeF23sstG4PXg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XPNabNMeTd3xp4/oL6xY4DAHkk8VXObhP4I0DNk6FPyfXq1j85FzopSzLuMJRssDt k6ZDnUezEAZoZvvatP+atqJMhgrI+3pTRslC61MRsOukcsls0v9SOKs0hsRKGw5SN6 A2VWzW/guzWkIVxbCp0oZUdDyDNQWDD5ZFljG0Fc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" Subject: [PATCH 4.19 20/99] ipv6: fix kernel-infoleak in ipv6_local_error() Date: Mon, 21 Jan 2019 14:48:12 +0100 Message-Id: <20190121134914.681139794@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190121134913.924726465@linuxfoundation.org> References: <20190121134913.924726465@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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 7d033c9f6a7fd3821af75620a0257db87c2b552a ] This patch makes sure the flow label in the IPv6 header forged in ipv6_local_error() is initialized. BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 CPU: 1 PID: 24675 Comm: syz-executor1 Not tainted 4.20.0-rc7+ #4 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 kmsan_internal_check_memory+0x455/0xb00 mm/kmsan/kmsan.c:675 kmsan_copy_to_user+0xab/0xc0 mm/kmsan/kmsan_hooks.c:601 _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 copy_to_user include/linux/uaccess.h:177 [inline] move_addr_to_user+0x2e9/0x4f0 net/socket.c:227 ___sys_recvmsg+0x5d7/0x1140 net/socket.c:2284 __sys_recvmsg net/socket.c:2327 [inline] __do_sys_recvmsg net/socket.c:2337 [inline] __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334 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:00007f8750c06c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000002000 RSI: 0000000020000400 RDI: 0000000000000005 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8750c076d4 R13: 00000000004c4a60 R14: 00000000004d8140 R15: 00000000ffffffff Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline] kmsan_save_stack mm/kmsan/kmsan.c:219 [inline] kmsan_internal_chain_origin+0x134/0x230 mm/kmsan/kmsan.c:439 __msan_chain_origin+0x70/0xe0 mm/kmsan/kmsan_instr.c:200 ipv6_recv_error+0x1e3f/0x1eb0 net/ipv6/datagram.c:475 udpv6_recvmsg+0x398/0x2ab0 net/ipv6/udp.c:335 inet_recvmsg+0x4fb/0x600 net/ipv4/af_inet.c:830 sock_recvmsg_nosec net/socket.c:794 [inline] sock_recvmsg+0x1d1/0x230 net/socket.c:801 ___sys_recvmsg+0x4d5/0x1140 net/socket.c:2278 __sys_recvmsg net/socket.c:2327 [inline] __do_sys_recvmsg net/socket.c:2337 [inline] __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 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] ipv6_local_error+0x1a7/0x9e0 net/ipv6/datagram.c:334 __ip6_append_data+0x129f/0x4fd0 net/ipv6/ip6_output.c:1311 ip6_make_skb+0x6cc/0xcf0 net/ipv6/ip6_output.c:1775 udpv6_sendmsg+0x3f8e/0x45d0 net/ipv6/udp.c:1384 inet_sendmsg+0x54a/0x720 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] __sys_sendto+0x8c4/0xac0 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1796 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Bytes 4-7 of 28 are uninitialized Memory access of size 28 starts at ffff8881937bfce0 Data copied to user address 0000000020000000 Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/datagram.c | 1 + 1 file changed, 1 insertion(+) --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -341,6 +341,7 @@ void ipv6_local_error(struct sock *sk, i skb_reset_network_header(skb); iph = ipv6_hdr(skb); iph->daddr = fl6->daddr; + ip6_flow_hdr(iph, 0, 0); serr = SKB_EXT_ERR(skb); serr->ee.ee_errno = err;