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=-6.0 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 50701C282CE for ; Wed, 24 Apr 2019 17:19:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E9372192D for ; Wed, 24 Apr 2019 17:19:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556126359; bh=evnLSChIstEjmXuYnv/uCVyHAD2LOd9UMq5k+PhQU/w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=AGH8CfJQynF/Czt63nSw597IlfhCgzFA8IIgXWT/DaamJE+cRE65yAkz73JT7Eanf usjdvI9JkWDK59q+t+3t+qDARKWHpz8ZTdcF78tKJEkYFznaYu0bP8IFH6Mooku/nH k0+kc+ydduaCJfanjcW8qHJDmzF/wUAmVnNpUjzY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388973AbfDXRTS (ORCPT ); Wed, 24 Apr 2019 13:19:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:44382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388945AbfDXRTO (ORCPT ); Wed, 24 Apr 2019 13:19:14 -0400 Received: from localhost (62-193-50-229.as16211.net [62.193.50.229]) (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 E6B5321908; Wed, 24 Apr 2019 17:19:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556126353; bh=evnLSChIstEjmXuYnv/uCVyHAD2LOd9UMq5k+PhQU/w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pTGUubLToknx2fWXiwQ4Ta/2LXFrQAl9UYs+HKc9BX6MEj8zin3kDi2RMsCfkklLR 7BT+Isc6QOdY400hqK/1xwESqbMYqrSrzaYRPyB+3g9hFUqqQZu8ahAc0fRZp8Edfl 8ynlh5TRy6HZZD1PxQ2JcC0Hd5Q72lV5BEckguL8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+86b5c7c236a22616a72f@syzkaller.appspotmail.com, Xin Long , Alexander Potapenko , Neil Horman , "David S. Miller" Subject: [PATCH 4.4 082/168] sctp: initialize _pad of sockaddr_in before copying to user memory Date: Wed, 24 Apr 2019 19:08:46 +0200 Message-Id: <20190424170928.695052288@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190424170923.452349382@linuxfoundation.org> References: <20190424170923.452349382@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Xin Long [ Upstream commit 09279e615c81ce55e04835970601ae286e3facbe ] Syzbot report a kernel-infoleak: BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 Call Trace: _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 copy_to_user include/linux/uaccess.h:174 [inline] sctp_getsockopt_peer_addrs net/sctp/socket.c:5911 [inline] sctp_getsockopt+0x1668e/0x17f70 net/sctp/socket.c:7562 ... Uninit was stored to memory at: sctp_transport_init net/sctp/transport.c:61 [inline] sctp_transport_new+0x16d/0x9a0 net/sctp/transport.c:115 sctp_assoc_add_peer+0x532/0x1f70 net/sctp/associola.c:637 sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline] sctp_process_init+0x1a1b/0x3ed0 net/sctp/sm_make_chunk.c:2361 ... Bytes 8-15 of 16 are uninitialized It was caused by that th _pad field (the 8-15 bytes) of a v4 addr (saved in struct sockaddr_in) wasn't initialized, but directly copied to user memory in sctp_getsockopt_peer_addrs(). So fix it by calling memset(addr->v4.sin_zero, 0, 8) to initialize _pad of sockaddr_in before copying it to user memory in sctp_v4_addr_to_user(), as sctp_v6_addr_to_user() does. Reported-by: syzbot+86b5c7c236a22616a72f@syzkaller.appspotmail.com Signed-off-by: Xin Long Tested-by: Alexander Potapenko Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/protocol.c | 1 + 1 file changed, 1 insertion(+) --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -598,6 +598,7 @@ out: static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) { /* No address mapping for V4 sockets */ + memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero)); return sizeof(struct sockaddr_in); }