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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 1917DC43381 for ; Sun, 31 Mar 2019 08:58:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D4EE220882 for ; Sun, 31 Mar 2019 08:58:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="l21epxRu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726581AbfCaI6Y (ORCPT ); Sun, 31 Mar 2019 04:58:24 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:43219 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726043AbfCaI6X (ORCPT ); Sun, 31 Mar 2019 04:58:23 -0400 Received: by mail-pl1-f196.google.com with SMTP id m10so3000424plt.10; Sun, 31 Mar 2019 01:58:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=0A00ALcQvAaZ3tVtlCaR5ibGYMH8nJIypDw4Ag9OU40=; b=l21epxRu6/pH9uAvz/xYcKtgqn7akb0sENCkCkz8++UjB6qXQawhIdIKaN7COi8Xzq purOnn72t75/P/DqyGS+0Zv8yHX2T34fMgmQO9wU0eQpJgyPhtz5MzUrus7QhpTsQ5uU 4MW8+35Pq4lN6qGn0+rY60e86df2uxI/CfzoJ+90fMs3gWsB6ShTBsxVfcsxwGZ9umgC CILY6TAc9njFpocMyOD04fJEpm0flNmogRLOxADJ4hEvXBdcIDAG+Y/GCU3KHOsB9b7z byWDR8T2ujUxpvOrwXLdCVBA0v9S5bdz158BDmoviVwqJnoG9HHrkcaklPcaJyc0lHEJ /lZg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=0A00ALcQvAaZ3tVtlCaR5ibGYMH8nJIypDw4Ag9OU40=; b=OXN1SG+PBD0gjiFtX0EQJn7biEry/ao06QZyONgzgsOJYCKo/VqMLyQiKreKEbm04t jyB3cGuLlxQ2/KKb0R6gX07Y65DibhhgyKU2sQCb22sW83CHzqcc83AAyGJe9YTtvoUZ vyyjOt7VY7Iw0qxBSomh6JWz6sXG9k68Cx6nTS69yZ8u8QgIFIAYgrGKpvICQNSH+Wrf 2V9JdRZDCDsZVmsNl8dh/9LEEJ3G5DL7PSWB0C8WE+CnFIn01S4+hAqSCziM+KWq7NJ2 3v5vlHLZ9HhkU5VO+my80CMtoR7dviHDoXrAG1yrrqIejOBhMSSnQ6I7ANaFfwGMF7Aw KuFQ== X-Gm-Message-State: APjAAAX1vN0clMqhV+0MnNwN+xf7iWcP+rlTZEXbGYKfADfjkA5vhgRg 9MDUsjnhAEDs0FTLWG19p3OQKIYxmv4= X-Google-Smtp-Source: APXvYqzFZK1tA2JU09e5N3AiPj0AwsvHj1oJpTj6b1UCiLLaQbenrSiLOSuHamM7Dpq1DXlnrNINyQ== X-Received: by 2002:a17:902:b60c:: with SMTP id b12mr57244820pls.261.1554022702990; Sun, 31 Mar 2019 01:58:22 -0700 (PDT) Received: from localhost ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id t3sm8336728pgv.39.2019.03.31.01.58.21 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 31 Mar 2019 01:58:22 -0700 (PDT) From: Xin Long To: network dev , linux-sctp@vger.kernel.org Cc: davem@davemloft.net, Marcelo Ricardo Leitner , Neil Horman , syzkaller@googlegroups.com Subject: [PATCH net] sctp: initialize _pad of sockaddr_in before copying to user memory Date: Sun, 31 Mar 2019 16:58:15 +0800 Message-Id: X-Mailer: git-send-email 2.1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 --- net/sctp/protocol.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 6abc8b2..951afde 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -600,6 +600,7 @@ static struct sock *sctp_v4_create_accept_sk(struct sock *sk, 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); } -- 2.1.0